M.V. Agbunov

Antique pilotage of the Black Sea

Preface

The book offered to the reader is dedicated to the most interesting geographical work of ancient times - “Periplus of Pontus Euxine,” which was compiled in the 2nd century. based on earlier sources by the famous Roman writer and statesman Flavius Arrian. This is one of the oldest sailing directions in the Black Sea. The word “periplus” itself translated from ancient Greek means “swimming around”. In this book we will take a journey around the Black Sea, which in ancient times was called the Pontus Euxine, i.e. the Hospitable Sea.

When familiarizing ourselves with the geological history of the Black Sea, with the paleogeographical changes that have occurred here over the past millennia, both under the influence of natural factors and as a result of active human intervention, we see that the sea level experienced fluctuations, as a result of which the shores retreated and some islands disappeared , others appeared, river beds and mouths moved, estuaries and bays were formed, important ports became unnavigable and died out, natural conditions changed.

The changes that took place were one of the reasons that many issues of the ancient geography of the Black Sea region aroused lively debates and discussions for a long time. The most complicated problems remained unclear for a long time.

The solution to all these problems became possible only in recent decades, when comprehensive research by geologists, paleo-geographers, historians, archaeologists, paleontologists, paleoclimatologists and other specialists was widely launched in the Black Sea. The joint work of these specialists produces amazing results. Many of the mysterious and at first glance contradictory information of ancient geographers, the inconsistencies and discrepancies in distances that existed in them, became clear. Most of them are explained, as a rule, not by the mistakes of ancient authors, but by the paleo-geographical changes that have occurred.

An integrated approach has opened up new opportunities for constructing more accurate paleogeographic reconstructions, which are confirmed by cartographic and archaeological data.

Medieval sea compass charts, the so-called portolans, are of particular value. They reflect the position of the ancient coastline, which in the Middle Ages was still similar in many details to the configuration of ancient times.

According to the obtained paleogeographic reconstructions, on almost the entire coastline the sea has been advancing quite intensively onto the land over the past two millennia. As a result, over the past centuries, a significant strip of coastline has been destroyed in many places - from several tens of meters to a kilometer or more. Therefore, the coastal part of many ancient cities and settlements was under water. And some settlements are completely flooded. To search for them, targeted underwater archaeological research is carried out. Thus, with the help of divers and scuba divers, some “disappeared” cities and settlements, harbors and islands that were mentioned in the works of ancient authors were found.

This book is based on the results of comprehensive research conducted by the author over the past decade. The author thanks his colleagues and workmates for their comprehensive assistance in this research and assistance in writing the proposed book. The insert shows a photo of the author, as well as V. A. Suetin, to whom the author expresses his deep gratitude.

When quoting passages from the works of ancient authors, references are given according to the generally accepted system. Roman numerals indicate a book, Arabic numerals indicate a chapter or paragraph. At the end of the book there is a list of abbreviations of the main literary sources.

Introduction

Of all the seas, it is by its nature the most amazing.

The Black Sea has long attracted the attention of ancient Greek sailors. According to legend, the first to enter it were the Argonauts. Over time, occasional voyages became more regular. In the 8th century BC e. The so-called Great Greek colonization began, which drew the Black Sea basin into its orbit. In the VIII–VI centuries. BC e. Dozens of ancient Greek cities and settlements appeared here. They existed for about a thousand years in close cooperation with local tribes and left a noticeable mark on the history of the Black Sea region.

One of the centers of the migration movement was the city of Miletus, a major economic and cultural center on the Asia Minor coast, which became the metropolis of many Pontic cities. Brave sailors embarked on long, risky voyages in search of new lands, sources of raw materials, and markets. Gradually they mastered the Black Sea, which was harsh for them compared to the Mediterranean, which at first was called Pontus Aksinsky (Inhospitable Sea), and then renamed Pontus Euxinsky (Hospitable Sea).

So the Black Sea coast of our country became one of the busiest regions of the ancient world and the then ecumene in general. We mastered it gradually, in several stages. After in 657/656 BC. e. At the mouth of the Istra (Danube) on the territory of modern Romania, the city of Istria arose, and the ancient Greeks began to develop the coast of Scythia, stretching from Istra to Tanais (Don). In 645/644 BC. e. the Greeks settled at the mouth of such large waterways as Borysthenes (Dnieper) and Hypanis (Southern Bug). This is the earliest ancient Greek settlement on the territory of our country, located near the mouth of the Dnieper-Bug

Rice. 1. Pont Euxine

estuary on modern Berezan Island. Then, apparently, at the turn of the 7th–6th centuries. BC e. on the right bank of the Bug Estuary near the modern village. Parutino the city of Olvia appeared, which translated means “Happy”. During the 6th century. BC e. The Northern and Eastern Black Sea region was covered with a dense chain of ancient Greek cities and settlements. In the lower reaches of Tiras (Dniester) Ophiussa, Nikonium arose, on the site of modern Evpatoria - Kerkinitida, on the territory of modern Sevastopol - a small settlement on the site of the future Chersonese, in the depths of the Feodosian Gulf - Feodosia, which has retained its name to this day. Many cities appeared on the shores of the Cimmerian Bosporus (Kerch Strait): on the site of Kerch - Panticapaeum, the capital of the future Bosporan Kingdom, somewhat to the north of it - Myrmekiy, Porthmiy, and to the south - Tiritaka, in modern times. Geroevka - Nymphaeum. These cities are located on the European side of the strait, which in ancient times was considered the border between Europe and Asia. On the Asian side of the Bosporus, near the present village of Sennaya, Phanagoria and Kena were founded, on the site of modern Taman - Hermonassa. In the Eastern Black Sea region, where the city of Poti is now located, Fasis appeared, founded at the mouth of the river of the same name (modern Rioni), and in Sukhumi Bay - Dioscurias.

Each of the ancient cities of the Black Sea region went through its own unique path of historical development. But still, in general, their story has a lot in common. These cities existed in a dense environment of local tribes, and their history is mainly the history of the relationship between the Greeks and barbarians (as the Greeks called all other peoples and tribes). And these relations, of course, were not stable over the centuries. Peaceful times alternated with military clashes, equal coexistence with various forms of military-political and economic dependence of ancient cities on the local population.

In their daily life in a new place, the Greeks were engaged in their usual activities: agriculture, cattle breeding, hunting, fishing, and various crafts. Trade with local tribes and Mediterranean centers occupied a large place. Expensive dishes, various jewelry, luxury items, wine, olive oil, spices were brought from Greece in exchange for bread, of which there was always an acute shortage, salted fish, various agricultural raw materials and other goods.

The tasks facing the settlers largely determined the choice of place to found the city. In this case, the following necessary factors were usually taken into account first: 1) a bay convenient for the harbor; 2) trade routes to the hinterlands; 3) fertile lands; 4) sources of drinking water; 5) an elevated place taking into account defensive capabilities; 6) building material; 7) natural resources, etc. The favorable geographical location largely determined the further development of the city. And such an advantageous position was provided by a combination of the listed factors in one order or another, depending on each specific case.

The reader will not find here a consistent presentation of the history of the ancient cities of the Black Sea region. Such a huge and responsible work is not part of the author’s task. The purpose of this book is much more modest - to acquaint the reader with Arrian’s periplus, with the most interesting questions of the ancient geography of the Black Sea, with the location of the cities and settlements, harbors and islands mentioned in the periplus, and with the main problems of their historical and geographical study.

Current page: 1 (book has 12 pages in total)

M.V. Agbunov
Antique pilotage of the Black Sea

Preface

The book offered to the reader is dedicated to the most interesting geographical work of ancient times - “The Periplus of Pontus Euxine,” which was compiled in the 2nd century. based on earlier sources by the famous Roman writer and statesman Flavius Arrian. This is one of the oldest sailing directions in the Black Sea. The word “periplus” itself translated from ancient Greek means “swimming around”. In this book we will take a journey around the Black Sea, which in ancient times was called the Pontus Euxine, i.e. the Hospitable Sea.

An integrated approach has opened up new opportunities for constructing more accurate paleogeographic reconstructions, which are confirmed by cartographic and archaeological data.

Introduction

Of all the seas, it is by its nature the most amazing.

Herodotus

Rice. 1. Pont Euxine

estuary on modern Berezan Island. Then, apparently, at the turn of the 7th–6th centuries. BC e. on the right bank of the Bug Estuary near the modern village. Parutino the city of Olvia appeared, which translated means “Happy”. During the 6th century. BC e. The Northern and Eastern Black Sea region was covered with a dense chain of ancient Greek cities and settlements. In the lower reaches of Tiras (Dniester) Ophiussa, Nikonium arose, on the site of modern Evpatoria - Kerkinitida, on the territory of modern Sevastopol - a small settlement on the site of the future Chersonesos, in the depths of the Feodosian Gulf - Feodosia, which has retained its name to this day. Many cities appeared on the shores of the Cimmerian Bosporus (Kerch Strait): on the site of Kerch - Panticapaeum, the capital of the future Bosporus Kingdom, somewhat to the north of it - Myrmekiy, Porthmiy, and to the south - Tiritaka, in modern times, with. Geroevka - Nymphaeum. These cities are located on the European side of the strait, which in ancient times was considered the border between Europe and Asia. On the Asian side of the Bosporus, near the present village of Sennaya, Phanagoria and Kena were founded, on the site of modern Taman - Hermonassa. In the Eastern Black Sea region, where the city of Poti is now located, Fasis appeared, founded at the mouth of the river of the same name (modern Rioni), and in Sukhumi Bay - Dioscurias.

In this case, the main attention is paid to the Black Sea coast of our country.

With the development of Pontus Euxine, ancient geographers and historians became interested in this area, leaving us with the most valuable descriptions of this basin. These descriptions tell about the sea itself, its coast, the islands, the rivers flowing into it, they name the ancient cities and settlements that existed here, harbors and anchorages, they mention local tribes, their history, way of life, and customs. These are the “History” of Herodotus, the periplus of Pseudo-Scylacus, the perieges of Pseudo-Skymnus, “Geography” of Strabo, “Natural History” of Pliny the Elder, “Description of the Inhabited Earth” of Dionysius, “Geographical Guide” of Claudius Ptolemy and other works. Arrian's periplus occupies a special place among them. In 134, as the ruler of Cappadocia, one of the provinces of the Roman Empire on the southern shore of the Black Sea, he sailed from Trebizond (modern Trabzon in Turkey) to Dioscurias - Sebastopolis. The navigator compiled a report to Emperor Hadrian about this trip in the form of a periplus, written both on the basis of personal impressions and with the involvement of other sources 1
Rostovtsev M. I. Scythia and Bosporus. L., 1925. P. 63 et seq.

This work has come down to us in a single manuscript of the 10th century. (Palatine manuscript and its London copy of the 14th–15th centuries). But this Palatine-London edition of the periplus turned out to be, as we will see later, far from complete.

Let's take a brief look at Arrian's biography. His full name is Quintus Eppius Flavius Arrian. He was born around 90–95 in Asia Minor, in the rich Roman province of Bithynia, in the city of Nicomedia. He received an excellent education, spoke Greek and Latin, studied rhetoric, philosophy, and military affairs. He quickly rose through the ranks and became a senator. Somewhere in 121–124. received the title of consul. In 131–137 as the personal legate of Emperor Hadrian, he ruled Cappadocia, one of the important Roman provinces in Asia Minor. Later, Arrian withdrew from state and military affairs and devoted himself to literary activities. In 147 he was elected as archon-eponym (one of the highest officials) in Athens. It is also known that in Nicomedia Arrian was elected priest of the goddesses of the underworld Demeter and Persephone. His further life path remains unknown.

As a writer, Arrian is best known for his main work, “Alexander's Campaign,” in which he describes the path of Alexander the Great to India. In addition, his major works “History of Bithynia” and “History of the Parthians” that have not reached us are known. The Periplus of Pontus Euxine occupies an important place in Arrian’s creative heritage.

It is worth dwelling on one more periplus of Pontus Euxine, which for a long time was attributed to Arrian. Then researchers came to the conclusion that Arrian was not its author, and began to call this work the periplus of Pseudo-Arrian or the periplus of the Anonymous author 2
For more details see: Skrzhinskaya M. V.“Periplus of Pontus Euxine” by Anonymous author // Research on ancient archeology of the Northern Black Sea region. Kyiv, 1980. P. 115 et seq.

It is based on Arrian's periplus (even an address to Emperor Hadrian has been preserved) with the addition of excerpts from the works of Pseudo-Scylacus, Pseudo-Scymnus, Menippus and other authors. It was compiled, according to scientists, during the Byzantine era in the 5th or 6th century. The compiler repeated information from Arrian and other sources almost without changes, added only some contemporary names and converted all distances that were given in stages into miles, using the standard accepted in Byzantine times: 1 mile = 7.5 stages.

Information from the periplus of Arrian and the Anonymous author are the most important sources for the study of many issues of ancient geography and history of the Black Sea region. Working with periplus is very interesting, but at the same time extremely difficult. These sources have attracted close attention from researchers for more than four centuries. At first, scientists continually encountered serious difficulties: the modern coastline did not correspond to the ancient descriptions, some distances did not coincide, in a number of places cities and settlements indicated in the periplus were missing, contradictions arose between written and archaeological data, etc. One One of the main difficulties is related to questions about the structure of Arrian’s periplus, its sources and their dating. Some researchers believed that all information, except for the description of the coast from Trebizond to Dioscurias - Sebastopolis, was added by the Byzantine author, others denied this, believing that the Palatine-London edition of the periplus belongs entirely to Arrian. And P. O. Karyshkovsky came to the conclusion that the Palatine-London edition was incomplete and that the Byzantine editor did not supplement, but, on the contrary, shortened Arrian’s text. Comparing scant information. Arrian about the interfluve of the Dniester and Danube with a more complete description of the Anonymous author, the scientist notes: “Rejecting the view of Arrian’s periplus as a work in which everything except the description of the coast between Trebizond and Sevastopol (Dioscurias) is an addition of Byzantine time, we cannot reject from the impression that it is precisely when describing the North-Western Black Sea region that the hand of the Byzantine editor is very noticeable" 3
Karyshkovsky P. O. On the issue of the ancient name of the Roksolan settlement // MASP. 1966. Vol. 5. P. 153.

The question of the sources and dating of Arrian’s information also caused a lot of discussion. Most researchers believed that the data presented in the periplus were collected by Arrian himself and correspond accordingly to the time of his life. But further research showed that some historical events and military-political situations noted in the periplus could not have taken place at the beginning of the 2nd century. Scientists attribute events such as the abandonment of Feodosia, the decline of the harbor of Atheneon, the transition of the Lampada and the harbor of Symbols to the Tauri, and Kalos-Limena to the Scythians to an earlier time - to the second half of the 2nd century. BC e. 4
Right there. pp. 152–153. The same date was also assumed by M.I. Rostovtsev in the book “Scythia and Bosporus” (p. 68, note 1), who still gave preference to another period, namely the end of the 1st century. (p. 67), suggesting from here that Arrian described the Northern Black Sea region “on the basis of information he collected from persons personally familiar with the current state of the areas that interested Arrian” (p. 68).

P. O. Karyshkovsky refers to the same period with the example of the city of Thira: in the time of Arrian, Thira was a fairly large city, minted its own coins and could not be classified as deserted and nameless places.

The question of the dating and origin of the information of the Anonymous author about the North-Western Black Sea region, which is absent from Arrian, is also extremely important. Analyzing these passages, M. I. Rostovtsev convincingly rejected the opinion of K. Muller, who attributed them to the periplus of Menippus, and showed that they were taken from an earlier periplus of the 4th - early 3rd centuries. BC e., the author of which was, perhaps, Eratosthenes, the largest ancient geographer 5
Rostovtsev M. I. Scythia and Bosporus. L., 1925. pp. 69–73.

These, in general terms, are the main source study problems of studying the periplus of Arrian and, to a certain extent, the periplus of the Anonymous author, which is related to him. These problems boil down mainly to the following questions.

1. What sources underlie Arrian’s periplus?

2. What time do these sources date from?

3. Why are some areas, for example the Cimmerian Bosporus, the North-Western Black Sea region, described by Arrian rather sparsely?

5. How long ago do these passages date from?

Quite a lot of specific historical and geographical questions related to the objects mentioned in the periplus have accumulated. They are associated mainly with the search for cities and settlements indicated by the geographer, harbors and anchorages, rivers and islands, with the localization of local tribes, with the interpretation of certain historical and military-political events, etc.

In resolving all these issues, the main task was a detailed, comprehensive study and comparative analysis of information from Arrian and the Anonymous author. The conducted research led to the following findings and conclusions.

Arrian's Periplus has not reached us completely. This is evidenced, as we will see later, by information cited by Procopius of Caesarea and Leo the Deacon with reference to Arrian’s periplus that is not in the text under consideration.

Arrian significantly shortened his source - the periplus of an earlier time. This is clearly shown by more complete parallel passages from the periplus of the Anonymous author, dedicated to the North-Western Black Sea region, the coast of the Cimmerian Bosporus and other individual areas. The distances given here are completely identical, the style of presentation is similar, the level of presentation of information and many seemingly insignificant, but very significant details. All this would be impossible if different sources were compiled. A clear indication of this is the abundance in the Anonymous author of sharply striking additions and insertions taken from the works of Pseudo-Skylak, Pseudo- Skimna and other ancient geographers.

It follows that all the information from the Anonymous author’s periplus, which is not available from Arrian and the other mentioned geographers, was taken not from some unknown source, as is commonly believed, but from the same periplus that Arrian used and shortened.

Thus, the periplus of the Anonymous author basically consists of the text of Arrian, supplemented by passages from Pseudo-Scylacus and Pseudo-Scymnus. This geographical work could not have been compiled in early Byzantine times, as is commonly believed. This is contradicted, firstly, by the very name “Periplus of the Euxine Pontus of both continents or localities along the shores of Asia and along the shores of Europe in this order: periplus of Pontic Bithynia; periplus of Paphlagonia; periplus of two Pontus; periplus of the European parts of Pontus Euxine." Here, in fact, the Black Sea provinces of the Roman Empire are named. And in the VI century. these provinces, like the empire itself, no longer existed. And no one would think of calling their geographical work that way.

Secondly, no one would indicate in such detail and scrupulously long-defunct cities and settlements, give no longer needed distances between these ancient ruins, and especially any specific information, for example, recommend to seafarers a long-destroyed harbor or an unsuitable anchorage . Thirdly, the entire presentation of the periplus is permeated with the spirit of ancient times: real cities and settlements, harbors and islands, anchorages and other geographical objects that are necessary for the navigator right now appear everywhere; after all, for this, in fact, the periplus itself is intended. Fourthly, the very name of the periplus and the whole spirit of the description are characteristic of Arrian’s time. Fifthly, the text contains appeals to Emperor Hadrian, and a mention in the present tense of the kings who received power from him, and a number of other specific facts and details of that period. And most importantly, in several places the narration is told on behalf of Arrian himself. After all, the Byzantine author would never have left it all in this form.

So, all the facts and considerations presented here lead to the conviction that the geographical work called the periplus of the Anonymous author is nothing more than the same periplus of Arrian, expanded and supplemented by the author himself. This text actually ended up in the hands of a Byzantine geographer. But he only converted stages to miles, since stages were no longer used in his time, and gave some contemporary names.

Consequently, the manuscripts known as the Periplus of Arrian and the Periplus of the Anonymous Author are not two different works, but short and extended editions of the same work - the Periplus of Arrian. The brief edition was framed as an official report to Emperor Hadrian and dedicated to him. Arrian then revised his work, expanded and supplemented it with other sources.

Such cases are known and not surprising. For example, we can note the existence of two editions, one brief and the other more detailed, of the work of the famous medieval geographer Plano Carpini. In this regard, he writes the following: “Therefore, let no one be surprised to find this manuscript more detailed and more correct than all the others, since since I acquired some leisure, I have replenished, corrected and finished it in those parts. where it was incomplete" 6
Giovanni del Plano Carpini. History of the Mongols; Guillaume de Rubruk. Travel to eastern countries. M., 1957. P. 9.

The basis of Arrian's periplus is, as already mentioned, a periplus dating back to no later than the 3rd century. BC e., most likely by the end of the 4th - beginning of the 3rd century. BC e. Of course, some information can and does relate, as noted, to an earlier or later time. In addition, part of the data dates back to the time of Arrian himself and his other sources - Pseudo-Scylacus, Pseudo-Skymnus and other geographers. The name of the author of this periplus has not been preserved. And we cannot confidently say his name. His periplus was used, as already mentioned, by Strabo and other geographers.

Thus, the available data provide, in my opinion, enough grounds to consider the so-called periplus of the Anonymous author as an expanded edition of Arrian’s periplus. Of course, this issue requires further study and additional argumentation. But even at the current stage of development, it seems to me quite convincing. Therefore, in subsequent chapters, for a clearer presentation of the problems under consideration, Arrian’s periplus will be called a short periplus, and the so-called periplus of the Anonymous author will be called a full periplus.

Let's look at one more question. For several centuries, scientists have been trying to solve one of the main problems - to determine the location of the settlements indicated in the periplus, find them on the ground and identify them with known settlements, settlements and other objects. The task turned out to be extremely difficult. The locations of such large cities as, for example, Olbia, Chersonesos, Panticapaeum, etc., were established without much difficulty. Their majestic ruins have been known for a long time, and coins and marble slabs with inscriptions found there confirmed the correct identification of these cities. The situation was much more difficult with small settlements. The ruins of these points do not particularly stand out among other, nameless settlements. As a rule, they did not mint their own coins, inscriptions are rare here, so hopes for any find that would confirm the name of a small city or village remain small. Therefore, the main, and sometimes the only data for such localizations is periplus information about the distances between the mentioned points. But even here, researchers faced great difficulties.

Firstly, it was unclear by what stage the distances given in the periplus were measured. The fact is that in Greece there were several stages of different sizes. Which of them did the compiler of the periplus use? Researchers have determined the length of its stage in a variety of ways: 157.7 m, 178 m, 185 m, 197 m, 200 m. In recent years, many scientists have given preference to a stage of 197 m. This figure is obtained from the information of the Anonymous author, who repeats those taken from Arrian describes the distances in stages and immediately recalculates them in miles, for example: “from the city of Panticapaeum to Cimmeric 240 stadia, 32 miles” (§ 76). From this ratio it turns out that 7.5 stages are equal to 1 mile, i.e. 1480 m. It follows that the stage is equal to 197 m. But the researchers did not come to a consensus. And the use of different stages in the calculations led, of course, to significant discrepancies. This discrepancy in distances gave rise to many different points of view. It got to the point that they were looking for the same point in five, six, or even ten different places. Therefore, we will try to resolve the issue of Arrian's stage. Calculations based on the ratio of stages and miles are simple, reliable and, of course, cannot raise any substantive objections. After all, this ratio is confirmed by direct indication of sources. For example, in the scholia to Dionysius’s “Description of the Earth” it is clearly stated: “The stade has a length equal to the hippodrome. Seven and a half stages make one mile” (§ 718, VDI, 1948, No. 1, p. 261). It would seem that the question is clear: Arrian’s stade is equal to 197 m. But with such a recalculation, absolutely all the distances between known, firmly localized cities indicated in the periplus turn out to be much greater than the actual ones. How can we be here?

I had to take a different path: to calculate the distances between firmly localized settlements mentioned in the periplus. For greater accuracy, relatively small sections of the path were taken. All measurements were carried out on large-scale maps and verified with data from modern navigational surveys. The calculations cover almost the entire Black Sea coast. The results obtained showed that the Arrian stage is approximately 157 m 7
Agbunov M. V. Mysteries of Pontus Euxine. M., 1985. pp. 52–54.

In other words, the stages of Eratosthenes are used here. This is not surprising, since the periplus, as we will see later, is based on materials dating specifically to Eratosthenes’ time. Let me also remind you of M.I. Rostovtsev’s assumption that when describing the North-Western Black Sea region, data were used, possibly from Eratosthenes himself.

So, the available data leaves no doubt that Arrian’s stade is equal to 157 m. And the Byzantine editor simply converted the available stade into miles according to the standard of 7.5:1 accepted at that time (and not 8:1, as was usually considered in ancient times) time) and thereby “extended” the indicated distances. His parallel numbers are in miles and still mislead some researchers. However, we must not take this conversion of stages into miles into account. Here you should only count stages in kilometers.

Secondly, discrepancies were discovered in the distances between the data of Arrian and other ancient geographers. For example, the tower of Neoptolemus in the complete periplus is indicated 120 stadia west of the mouth of Thera (§ 89), and Strabo places it “at the mouth of Thera” (VII, 3, 16).

The city of Nikonium was located, according to the complete periplus, 30 stadia from the navigable river Thera (§ 87), and according to Strabo, 140 stadia above the mouth of Thera (VII, 3, 16). Arrian indicates five mouths of the Ister, while other geographers name six or seven mouths. These and other inconsistencies, discrepancies and contradictions, the list of which is easy to continue, significantly complicated the work with sources. In such cases, scientists were faced with a traditional question: which of the ancient geographers was right and which was wrong? Whose information should be given priority? This approach undermined the authority of ancient writers, caused distrust in their works and significantly complicated the solution of many problems of ancient geography and history of the Black Sea region,

Thirdly, in some cases, the information from the periplus was not confirmed by research on the ground: in those places where, according to the given distances, this or that settlement should have been located, there were no traces of its existence. This cast doubt on the data of the sources, strengthened distrust in them and complicated the already difficult work on the periplus.

A radical change in the solution of the problems under consideration has emerged in recent decades, when comprehensive research by geologists, paleogeographers, historians, archaeologists, paleontologists, paleobotanists, paleoclimatologists and other specialists has widely developed in the Black Sea region. Paleogeographic data occupied an important place in these joint developments. It was paleogeography that provided the key to solving many complex, extremely confusing and seemingly insoluble questions.

Paleogeographers have firmly established that in ancient times, during the period of the so-called Phanagorian regression, the level of the Black Sea was lower than the modern level by at least 5 m 8
Fedorov P.V. Post-glacial transgression of the Black Sea and the problem of changes in ocean level over the last 15 thousand years // Fluctuations in the level of seas and oceans over 15,000 years. M., 1982. P. 154.

This regression received its name from the ancient city of Phanagoria, where, as a result of underwater work under the leadership of V.D. Blavatsky, submerged structures were examined, clearly indicating a lower sea level in the 5th–3rd centuries. before i. e. Then the sea began to rise - the Nymphaean transgression (named after the city of Nymphaeum).

By the middle of the 1st millennium, sea level apparently approached modern levels. In the XIV–XV centuries. a regression followed again, called Korsun after the medieval Korsun (ancient Chersonese, modern Sevastopol). After this regression, a new rise in sea level began, which continues to this day. These sea level fluctuations, associated with changes in the level of the World Ocean, tectonics, continental moisture and other factors, were one of the main reasons for many paleogeographical changes that occurred on the Black Sea coast over the past 2.5 thousand years.

As it turns out, at lower sea levels during the Phanagorian regression, the coastline looked different in detail. The ancient coast ran from several tens to several hundred meters to the sea. Estuaries and small bays were much narrower and shallower. And some of them did not exist at all then. The rivers were much fuller. The climate was apparently milder. In the lower reaches of rivers and estuaries there are dense forests and copses rich in game.

During the Nymphaean transgression, the sea flooded the coastal lowlands and river mouths. The shore retreated and changed its configuration in detail. Previously non-existent estuaries and bays were formed. Some islands disappeared, others appeared. Under the influence of many factors, river mouths and main channels moved, some branches became shallow and unnavigable, others became more full-flowing. The sea flooded and destroyed the coastal part of the land. And therefore, many ancient cities and settlements were partially or completely under water.

These and other paleogeographic changes became one of the main reasons for many discrepancies in distances and inconsistencies between the information of ancient geographers and modern data. For example, the tower of Neoptolemus is indicated by Strabo at the mouth of the Tyre, and by Arrian - 120 stadia west of the mouth, not because one of the geographers allegedly made a mistake. The fact is that during the time that separates these sources, the mouth of the Tira has moved about 20 km to the east. And the tower of Neoptolemus, previously located at the mouth of the Tyre, was now 120 stadia to the west. Both ancient authors indicate it in the same place, although at first glance there is a clear discrepancy. And in those cases, for example, when in the place indicated by the source there are no traces of the mentioned settlement, the matter, again, is not a geographer’s error, but the paleogeographical changes that have occurred. This point, presumably, was destroyed by the sea, and we must look for its traces not on land, but under water, where the coastline passed in ancient times. As a result of underwater research with the help of scuba divers and divers, dozens of ancient settlements flooded by the sea have already been found.

An integrated approach has opened up new opportunities for constructing more accurate paleogeographic reconstructions, which are confirmed by cartographic and archaeological data.

Introduction

Of all the seas, it is by its nature the most amazing.

Rice. 1. Pont Euxine

General informationabout Blacksea. This navigation guide provides a description of the shores of the Black Sea, and also the Black Sea - the Mediterranean Sea of the Atlantic Ocean - is the easternmost of its seas and is a deep body of water stretching from west to east between Europe and Asia Minor. The greatest length of the Black Sea along the parallel 42°30" north latitude from the top of the Burgas Bay to the Caucasian coast north of the Redut-Kale roadstead is about 610 miles; the greatest width is between Cape Ochakovsky and Cape Baba (41°17"N, 31°24"E ) approximately 330 miles. In the narrowest part, the southern tip of the Crimean Peninsula, Cape Sarych, is only 142 miles away from Cape Kerempe (42°01" N, 33°20" E) on the Anatolian coast.

The Crimean Peninsula, which protrudes strongly into the sea from the north and the southern coast protruding in the middle part, divides the Black Sea into two parts: western and eastern. In the northeast, the Black Sea is connected to the Sea of Azov by the shallow Kerch Strait, through which a canal has been dug for large ships, and in the southwest, through the Bosporus Strait, it is connected to the Sea of Marmara and further through the Dardanelles Strait to the Aegean and Mediterranean Seas.

The Black Sea is of great economic importance for the countries whose shores it washes. Along it there are routes connecting its ports with the ports of the Mediterranean region.

Navigation in the Black Sea does not present any particular difficulties, since the dangers are located near the shores. On approaches to major ports and the Bosphorus Strait, due to the increasing volume of ship traffic, precautions should be taken.

To determine the location when sailing near the coast, you can use mountains, capes, various buildings, and in the open sea - radio navigation and astronomical aids.

The shores of the Black Sea belong to Ukraine, the Russian Federation, the Republic of Georgia, the Turkish Republic, the Republic of Bulgaria and Romania.

The first Pilot of the Black Sea was published in 1851. The materials for it were: an inventory of the shores of the Black Sea, made in 1825 by the expedition of E. P. Manganari; an inventory made in 1847 by tender commanders G.I. Butakov and I.A. Shestakov, later famous admirals, and the Pilot of the Eastern Coast of the Black Sea, compiled by warrant officer Taryshkin. The 1851 sailing route is a major work that has not lost its significance to this day.

Subsequent reissues of the sailing directions were made in 1867, 1892, 1903 and 1915 gg. were essentially a repetition of the first edition with the necessary changes and additions. Subsequently, the Black Sea Pilot was reprinted twelve more times. This edition is the eighteenth.

Shores The Black Sea is very diverse. There are high mountains of exceptional beauty, vast lowlands and monotonous, slightly hilly plains. Along with areas covered with rich subtropical vegetation, one can find areas completely devoid of any vegetation cover.

The shores of the Black Sea are subject to constant change throughout almost their entire length. The roughness of the sea in some places destroys the coast and levels out its outlines, in others it accumulates sediment, creating new land areas and changing the topography of the continental shallows.

Capes and sections of the coast protruding into the sea are subject to significant destruction; the rough seas and the surf constantly strive to level the coastline.

The general erosion and retreat of the banks slows down in areas of river mouths with intense solid sediment runoff; in the deltas of large rivers (Danube, Dnieper, Psou, Bzyb, Inguri, Rioni, Chorokh) during floods, an increase in sediments of up to 10 m is observed.

The northeastern coast of the Black Sea is mountainous. Here are the spurs of the Main Caucasian Ridge, which begins near the city of Anapa and stretches to the ESE, gradually moving away from the coast. The coastal mountains rise from northwest to southeast and reach their greatest height in the area of the port of Sochi. Further to the SE, the mountains, gradually lowering, move significantly away from the coastline in the area of the Kodori River valley. In some places, the spurs of the mountains come close to the sea, forming sheer cliffs; There are terrace-like slopes. Where the mountains recede somewhat from the coast, their slopes are gentler. The highest (3240 m) of the coastal mountains is Mount Chugush (43°48" N, 40°13" E).

The northeastern coast of the Black Sea from the port of Anapa to the port of Novorossiysk is mainly bordered by a rocky underwater ridge and is slightly eroded. In the area of the Anapa port near the coast, there is a constant movement of underwater sand banks.

The coast between capes Doob and Kodosh, composed of durable white and gray flysch, is destroyed due to weathering (by 2-3 cm per year).

The section of the coast between the ports of Tuapse and Sochi, composed of rocks of varying stability, has a leveled character; it is constantly destroyed by sea waves. This coast is lined with pebbly sediments that move during westerly storms. Mainly the southern shores of the capes are subject to destruction. Coastal protection is carried out in ports, near resort beaches and along the coastal railway.

The coast from the port of Sochi to the port point of Ochamchira is composed of various rocks; In some places it is bordered by pebble beaches of varying widths. The material for the beaches is solid sediment from many mountain rivers and rivers. Some of this sediment is absorbed by submarine canyons.

On the coast between Cape Pitsunda and the Gulf of Sukhumi there are several landslide areas (the village of Myussera, the city of New Athos, the village of Eshera).

The shores in the areas of the port point of Adler, the port of Sukhumi and the port point of Ochamchira are subject to the greatest destruction (1 -1.5 m per year).

The low-lying coast between the mouths of the Inguri and Rioni rivers is bordered by shallow water, which is formed by the outflows of these rivers; this coast is practically not eroded.

In the area between the mouths of the Rioni and Chorokh rivers, the destruction of the coast by sea waves varies: in the area south of the port of Poti 0.5 m, and in the area of the city of Kobuleti 1.5-2 m per year. North of the entrance to the port of Poti and in the area of Batumi Bay there is an accumulation of sediment.

Between the mouth of the Kodori River and the city of Kobuleti, the vast Colchis Lowland opens to the sea. Here, near the port of Poti, the Rioni River, the largest on the northeastern shore of the Black Sea, flows into the sea. Somewhat south of the mouth of the Rioni River, near the seashore, there is a large lake, Paleostomi, which was apparently once a bay. To the south of the city of Kobuleti, the coast becomes mountainous again, and in the area of the port of Batumi, the height of individual mountains is already more than 1500 m. The peaks of the Main Caucasus Range, many of which are clearly visible when sailing along the northeastern coast of the Black Sea, are covered with eternal snow.

The coastal spurs of the Caucasus Mountains are exceptionally rich in vegetation. The section from Novorossiysk and almost to Tuapse generally resembles the shores of the Mediterranean Sea, especially the shores of the northern part of the Balkan Peninsula. Coastal mountains up to a height of 150-200 m are covered with low-growing forests and bushes with leaves that fall in winter. Forests grow above this zone, and starting from a height of 400-500 m the vegetation acquires a mountain-steppe and mountain-meadow character.

In the area from Tuapse to Batumi, as you move south, the vegetation becomes increasingly rich. There are many evergreen deciduous trees and shrubs. The vegetation near the port of Batumi is especially luxurious. Cape Zeleny has a beautiful botanical garden with a wide variety of subtropical and tropical vegetation. At an altitude of 600-1200 m, the slopes of the coastal mountains are covered with deciduous forests, and then a strip of coniferous forest extends to approximately an altitude of 1900 m. Above the coniferous forest zone there are subalpine meadows, and at an altitude of 2200-3000 m there is an alpine belt, the vegetation of which is represented by low-growing alpine grasses.

The vegetation of the Colchis Lowland differs little in character from the vegetation of the lower tiers of the adjacent mountains, but it is dominated by broad-leaved forests with some admixture of evergreen species.

668 rivers and many temporary watercourses flow into the Black Sea from the northeastern coast, but all of them are short and non-navigable; Most rivers have a pronounced mountain character. The most significant of them, besides the Rioni, are the rivers Mzymta, Psou, Bzyb, Kodori, Enguri, Khobi and Chorokh.

The southern coast of the sea is also mountainous. The high Eastern Pontic and Western Pontic mountains stretch along it, forming one mountain range. The mountains reach their greatest height in the area located south and southwest of the port of Batumi. The tops of many mountains are covered with snow most of the year. The highest are the mountains Kachkar, Verchenik, Karchkhal and Shuval with heights of 3937, 3711, 3439 and 3377 m, respectively, and some other mountains located up to 25 miles from the coast between the port of Batumi and the city of Rize. To the west, the mountains gradually decrease and near the Bosphorus Strait their height is no more than 450 m.

Almost along its entire length, the southern coast is either steep and rocky, or descends to the sea in terraces. Occasionally there are low and sandy areas with rocky headlands protruding into the sea.

The slopes of the Pontic Mountains are covered with forests. Only near the villages can you find corn fields, orchards, vineyards and tobacco plantations. Citrus fruits are grown in the Rize area.

Numerous rivers flowing into the Black Sea from the southern coast have no navigational significance. In the upper, and in some cases also in the middle reaches, these rivers flow in turbulent streams among narrow valleys and gorges and only become calm at their mouths. Therefore, only on some rivers in certain sections it is possible to travel on rafts and flat-bottomed boats. The most important rivers of Turkey are the Kizil-Irmak rivers. Sakarya and Yeshil-Irmak are 1151, 790 and 416 km long, respectively.

To the west of the Bosphorus, the coast is relatively low; it has a reddish color in areas where it is formed by sand screes and a darker color in areas covered with vegetation. The headlands in this area are steep.

The only large peninsula on the Black Sea that significantly changes the general direction of the coastline is the Crimean Peninsula. This peninsula is connected to the mainland by the narrow Perekop Isthmus, to the west of which is the Karkinitsky Bay, and to the east from the Sea of Azov - Sivash Bay. The Kerch Peninsula, separated by the Kerch Strait from the Taman Peninsula, extends to the east of the Crimean Peninsula.

When sailing along the Black Sea coast, especially against areas with high, steep and steep banks that have good reflective properties, the conditions for radar orientation are favorable. Data on the radar characteristics of the coasts, information on the most noticeable radar landmarks and screenshots of the radar station with diagrams for them are placed in the manual “Radar Description of the Black Sea Coast” (No. 4249).

Islands. In the Black Sea, islands lie close to the coast; there are no large islands here. The exception is Zmeiny Island, located against the Danube River delta 19 miles from the coast. The depth in the middle part of the passage between the shore and Zmeiny Island is 27.5 m; no dangers found here. At the entrance to the Berezansky estuary lies the island of Berezan, and off the southern coast of the sea there is the island of Kefken; The islands and the islet are smaller in size than Zmeiny Island.

Near the northwestern coast of the Black Sea in the Tendrovsky Bay there is a group of low sandy islands, separated from each other by shallow passages. The Tendrovskaya and Dzharylgachskaya spits, stretching from the coast between the Dnieper estuary and the top of the Karkinitsky Bay, are cut through by narrow shallow passages and are islands.

Several islands lie in the Burgas Bay. In addition, near the coast, especially off the southern coast of the Crimean Peninsula, there are large surface stones and rocks.

Depths, bottom topography and soil. The Black Sea is a deep-sea basin with steep slopes. The 100 m isobath runs almost everywhere parallel to the coast, 1.5-10 miles from it. Only in the western and northwestern parts of the sea and at the entrance to the Kerch Strait does this isobath extend 20-30 miles, and in some places 80 miles from the coast. The northwestern part of the sea is the shallowest. The 100 m isobath runs here almost in a straight line from Cape Emine towards the port of Evpatoria, separating a large shallow area with depths gradually decreasing towards the north. The 200, 500 and 1000 m isobaths are parallel to the 100 m isobath; due to the steep depressions of the bottom, they pass at a very close distance from it. The bottom slope at these depths in some places reaches 14°. The transition from depths of 1000 m to greater depths is gradual. The central part of the sea has a depth of about 2000-2200 m; the greatest depth of the sea is 2210 m (43° 17" N, 33° 28" E).

Near the shallow shore, ridges may appear in the bottom topography, which are underwater shafts in the form of low sandy ridges stretching parallel to the coastline. The number of underwater rolls depends on the size of the surf zone: the wider the surf zone, the greater the number of rolls that can be formed. Since the initial emergence of underwater swells is associated with a critical depth equal to double the wave height, for the Black Sea the formation of these swells is associated with depths of 4-6 m. In a surf zone 600 m wide, three swells can form: the first - 100-120 m from shore, the second - 200-250 m from the first, the third - 400-500 m from the second. The height of the underwater ridges can reach half the original depth, that is, the depth from the base of the ridge will be twice as great as above the ridge. The profile of the underwater ridges is asymmetrical: the slope facing the sea is gentle, and the slope facing the shore is steep.

In the coastal strip of the sea, near rocky shores, the soil is predominantly pebbles and gravel, and in low areas of the shore there is sand. At depths of 20-30 m, the sand becomes silty, and at even greater depths the soil gradually turns into clayey silt. To depths of 200 m, large accumulations of shells are found in many places. In the northwestern part of the sea between the mouth of the Danube River and Cape Tarkhankut, at depths of 50-60 m, huge areas are occupied by algae. At depths of more than 200 m, the soil consists of viscous black silt saturated with hydrogen sulfide, which quickly turns gray in air. At depths of more than 1500 m, the silt is gray-blue; silt mixed with clay is found.

Terrestrial magnetism. Magnetic exploration of the area is satisfactory. In 1957-1960, 1965 and 1969. The routes of the R/V Zarya passed through the Black Sea. On the northern coast of the Black Sea there is a uniform and fairly dense network of ground-based magnetic observation points; There are only a few magnetic observation points on the southern coast of the sea.

Magnetic declination for the epoch of 1995 it varies from 4° E in the western part of the sea to 5.3° E in its eastern part. The direction of the isogons is northwest.

The average annual change in magnetic declination ranges from 3.3" E in the west of the sea area to 1.7" W in the east of the area.

The greatest deviation of the magnetic needle to the east is observed in the summer at about 8 o'clock, in the winter - at 9-10 o'clock local time. The minimum deviation of the magnetic needle to the west in winter and summer is observed at 14-15 hours local time.

Magnetic inclination varies from 64.2° N in the north of the area (port of Odessa) to 58.1° N in the south. The direction of the isoclines is close to latitudinal, in the east of the region it slightly deviates to the southeast.

The horizontal component of the magnetic field strength varies from 0.248 Oe in the south to 0.215 Oe in the north. The direction of the isodynamics is close to latitudinal.

Magnetic anomalies. There are several areas of magnetic anomalies in the Black Sea. The anomaly has a significant area of distribution in the Odessa Bay region; here the magnetic declination varies from 5° W to 9° E. Near the northeastern coast of the sea between the city of Kobuleti and the port of Batumi in the area of the magnetic anomaly, the declination varies from 1° W to 19° E. In the area of the Burgas Bay, the magnetic declination varies from 13° W up to 6° E. Small anomalous areas were found in the area of the port of Skadovsk (magnetic declination 8.4° E) and in the area of the port point of Khorly (magnetic declination 2.3° E).

Magnetic storms. The amplitude of quiet daily variations is about 4-5" in winter, 11-12" in summer. On days of large magnetic storms, the amplitude can be 1.5°.

General information about the Bosphorus Strait. This navigation guide describes the Bosphorus Strait, the Sea of Marmara and the Dardanelles Strait from the Black Sea to the Aegean Sea (a section of about 160 miles); they separate Europe from Asia.

The northeastern border of this area (entrance to the Bosphorus Strait from the Black Sea) lies between Capes Rumeli and Anadolu, and the southwestern border (entrance to the Dardanelles Strait from the Aegean Sea) lies between Capes Mehmetcik and Yenisehir.

Trade routes of great international importance pass through the Sea of Marmara and the Bosporus and Dardanelles. In international practice, the concept of “Black Sea straits” includes the Bosporus Strait, the Sea of Marmara and the Dardanelles Strait. The Black Sea Straits The Black Sea is connected through the Aegean Sea to the Mediterranean Sea and through the Strait of Gibraltar to the Atlantic Ocean, and through the Suez Canal and the Red Sea to the Indian Ocean.

The current regime of the Black Sea straits is determined by the Convention concluded in 1936 in the city of Montreux (Switzerland). It provides for free passage through the straits of any number of merchant ships from all countries of the world.

The length of the Bosphorus Strait is 16.2 miles; its greatest width is 2 miles, its smallest 4 kbt. The Sea of Marmara extends from east to west for 120 miles and from north to south for 40 miles. The length of the Dardanelles Strait is about 65 miles; its greatest width is 14.6 miles, its smallest 7 kbt.

In clear weather, sailing in the Bosphorus and Dardanelles straits, as well as in the Sea of Marmara, is quite easy. The straits and the sea are deep. There are few dangers far from the shore. A network of navigational aids provides navigation in these areas both day and night; there are many landmarks.

The use of radar can be of great help in determining the location of the vessel here, since mountainous and steep banks, islands and high capes are good visual and radar landmarks.

The main factors making navigation in the straits and the sea difficult are busy shipping and the presence of currents that can carry a ship to the coastal sandbank.

The Sea of Marmara and the Bosphorus and Dardanelles belong to the Republic of Turkey.

Shores. The steep shores of the Bosphorus Strait are formed by steep mountain slopes.

The northern shore of the Sea of Marmara is formed by a ridge of low mountains, the spurs of which descend to the sea. For most of its length this coast is steep. The mountain slopes facing the sea are covered with grass, in some places there are cultivated fields on the slopes, and in the valleys there are orchards and vineyards. A narrow, mostly rocky sandbank stretches along the coastline. The coast is cut by many rivers and streams that dry up in summer.

The Gulf of Izmit juts deep into the eastern shore of the Sea of Marmara, the northern shore of which is high and steep; the southern coast is less high and in some places is bordered by sandy beaches convenient for landing. The slopes of the mountains approaching the shores of the bay are covered with vineyards and orchards.

The southern coast of the Sea of Marmara is mountainous; Large bays jut into it: Gemliksky, Bandirma and Erdek. The slopes of the coastal mountains are mostly steep and covered with forest. In those places where the mountains recede somewhat inland, the coast is bordered by a sandy beach.

The European coast of the Dardanelles Strait is predominantly high and deep, and the Asian coast is low, but the terrain in this area is hilly, gradually rising inland.

The rivers flowing into the Dardanelles are almost dry most of the year, but during heavy summer and winter rains they turn into torrential torrents within a few hours.

Islands. The Princes' Islands are located on the approaches to the Bosphorus Strait from the south. Off the southern coast of the Sea of Marmara, near the entrance to Bandirma Bay, are the Mola Islands. In the western part of the sea there is a group of islands, which includes the largest of the islands in the Sea of Marmara - Marmara Island, as well as the Pashalimani Islands.

Near the southern coast of the sea between the Bozburun and Kapidag peninsulas there is the island of Imrali.

Depths, bottom topography and soil. The Bosphorus Strait is deep, the depths in its southern part reach 110 m. The soil in the strait is silt.

The central and eastern parts of the Sea of Marmara are deep; they contain depressions with depths of about 1200 m. The southern part of the sea is relatively shallow; the depth in it almost everywhere is less than 100 m. There are few dangers in the Sea of Marmara and they are located mainly near the shores. The uniformity of changes in depths off the coast of the Sea of Marmara makes it possible to determine in advance the approach of a ship to the shore in poor visibility. In the northern part of the Sea of Marmara, the soil is sand, silt, shell and coral, in the middle - gray silt, and in the southern part - silt, sand and shell. Rocks are found off the northwestern coast of the sea, in Erdek Bay, off the Kapi Dag Peninsula, off Marmara Island and off Imrali Island. At depths of up to 60 m, a lot of algae grows off the coast; At depths of up to 80 m, a sponge is found.

The Dardanelles Strait is deep. The depths in its northeastern part are 20-110 m, and in the central and southwestern part 20-95 m. The soil in the Dardanelles Strait is mainly silt, in places sand and silt, sand and shell, rock.

Terrestrial magnetism(1995 era). Magnetic study of the area described in this location is insufficient.

Magnetic declination varies from 3.4° E in the northeast of the area (Bosphorus Strait) (41°12"N, 29°05"E) to 3.8°E in the southwest of the Dardanelles Strait (Cape Mehmetcik). The isogon direction is close to the latitudinal one. The average annual change in magnetic declination is +0.05°.

The magnetic inclination varies from 58.2° N in the northeast of the region to 58° N in the southwest. The direction of the isoclines is close to the latitudinal one.

The horizontal component of the magnetic field strength increases from 0.247 Oe in the northeast of the region to 0.253 Oe in the southwest. The direction of the isodynamics is close to latitudinal.

Special physical and geographical phenomena. TO equipment. The shores of the Sea of Marmara and the Bosphorus and Dardanelles straits are provided with satisfactory navigation equipment.

On most capes protruding far into the sea, some islands and rocks have lighthouses, luminous signs and lights.

In ports and most harbors, lights are lit on piers, jetties and breakwaters.

When sailing in this area, remember that the location of poles and buoys, as well as the characteristics of lights, may change, so you should not rely on them completely.

There are several aerial radio beacons in the Sea of Marmara.

Aeronautical radio beacons may temporarily stop their operation or change its mode, about which no notice is given to mariners. The reliability of radio bearings obtained using aerial radio beacons is not very high.

Floating aids to navigation equipment can protect shoals protruding from the shore, banks, sunken ships, the most important bays in terms of navigation, fairways leading to ports and harbors, as well as approaches to road berths of oil terminals located in the area.

For guidance in limited visibility, there are sound alarms in some places.

Detailed information about aids to navigation in the described area is contained in the manuals “Lights of the Mediterranean Sea”, Part I (No. 2219), “Radio Navigation Systems” (No. 3010) and “Radio Engineering Aids to Navigation Equipment of the Black and Mediterranean Seas” (No. 3203), GUNIO MO .

The IALA Fencing System (Region A) operates in the waters of the area, a description of which is given in manual No. 9029, GUNiO MO.

Frequency of cloudy skies (Hydrometeorological conditions for navigation of ships in the described area are generally favorable. Difficulties may arise from October to May during stormy winds with squalls and sometimes due to fog.

When sailing in the straits, you must remember that depending on the wind direction, the direction and speed of surface currents can change significantly.

METEOROLOGICAL CHARACTERISTICS. The climate of the described area is subtropical (Mediterranean); It is characterized by rainy, mild winters (winter: December–February, spring: March–April, summer: May–September, autumn: October–November) and hot, dry summers. Spring and autumn are short-lived.

The Mediterranean climate is formed under the influence of the spur of the Azores High in summer and under the influence of cyclonic activity in winter.

The following types of weather are typical for the region of the Sea of Marmara and the Bosphorus and Dardanelles.

Weather type with predominant northeast winds observed at high atmospheric pressure over the sea. Distinctive features of this type of weather are the dominance of winds from the NE, a well-defined diurnal variation in wind speed (moderate during the day and weak to calm at night) and clear skies. The repeatability of this type of weather in July and August is about 100%, in June and September 70-80%, in May 30-40%.

Type of weather with a predominance of cold northern winds observed when there is an area of high atmospheric pressure over the Balkan Peninsula. This type of weather prevails in winter and is accompanied by cold, persistent winds from N from Central Europe; sometimes they reach the force of a storm.

Weather type with predominance of western and northwestern winds observed during the passage of southern cyclones. As they move towards the island of Cyprus and further to the northeast, winds from the W are first noted, and then winds from the NW. As a rule, with this type of weather there is an increase in cloudiness, humidity, precipitation, and a decrease in air temperature. This type of weather is most likely from December to February, occasionally observed in November and March, and very rarely from May to September.

Air temperature and humidity. The coldest months of the year are January and February, when the average monthly air temperature in the open sea is 7-8 °C, on the coast 4-6 °C. The absolute minimum air temperature is 16 °C (Istanbul, February).

The hottest months of the year are July and August; their average monthly temperature is 23-25 °C everywhere. The absolute maximum temperature is 39 °C (Istanbul, August).

Relative air humidity throughout the year in the open sea is 70-80%, and on the coast in winter 75-80%, in summer 55-75%.

Winds. In most of the described area, throughout the year, winds from the NE prevail, the frequency of which is 20-65%, and in summer and autumn in the open sea in some places 80-95%. Of the winds from other directions, winds from N are most likely (frequency rate 20-50%). In certain areas of the eastern coast of the Sea of Marmara, from November to February, winds from S are most often observed, from April to October - from W, SW and NE.

It should be borne in mind that in winter, weak winds from NE and N are usually accompanied by clear and cool weather, and in the Bosphorus even cold and sometimes foggy. When the winds from NE and N intensify, there is continuous cloudiness and occasional showers of rain, hail, and snow.

Winds from SW usually do not reach great strength and are accompanied by hot weather in summer and warm weather in the rest of the year. In winter, these winds become stronger and are accompanied by heavy rainfall and significant cloud cover. Sometimes, when leaving the Dardanelles Strait into the Aegean Sea, winds from the SW suddenly give way to squalls from the NE, which are very dangerous for small ships.

With winds from the NW, there are usually rain showers in winter. A harbinger of strong winds from the NW are white clouds rising over the European coast of the Sea of Marmara.

The average monthly wind speed in the described area throughout the year is 3-7 m/s throughout the year.

Calms are observed quite often, their frequency in most parts of the region is 10-20%, in the open sea in March - July in some places 25-40%.

Winds with a speed of 17 m/s or more are more often observed from October to May, when their frequency in the open sea is 2-8% per month. On the coast, the number of days with such winds during this period reaches 4 per month.

Storm winds most often blow from the N and NE, and sometimes from the S and SW. In the Bosphorus Strait, storms from the NW are rare; they are squally and often accompanied by rain.

Breezes are most developed from May to September. The sea breeze usually begins between 9 and 10 o'clock and reaches its strongest in the afternoon hours. In the evening it weakens and after sunset it is replaced by a coastal breeze, which has its greatest development at 2-3 hours, and then gradually weakens. The onshore breeze extends out to sea 10-15 miles from the coast, and the sea breeze penetrates inland 15-20 miles and is more stable and stronger than the onshore breeze.

In the described area, local winds are observed: “Dardanelles wind”, “Düsenwind”, “meltem”, “poyraz”.

Dardanelles wind (“Hellespont wind”, “datu”) - wind from NE in the Dardanelles Strait.

Duzenwind (“jet wind”, “blast wind”) is a strong wind from E or ENE from the Dardanelles Strait in the mountain passes of the northwestern coast of Turkey, penetrating into the Aegean Sea when a spur of high atmospheric pressure develops over the Black Sea.

Meltem (“meltemi”, “meltemya”) is a sudden onset summer wind from NE in the Bosphorus Strait. It begins in the morning, intensifies during the day (sometimes up to 20 m/s) and subsides in the evening.

Poyraz - strong wind from NE in the Bosphorus Strait.

Fogs in the open sea they are rarely observed, especially in summer. Their frequency from November to May does not exceed 4%. On most of the coast, the average number of days with fog per year usually does not exceed 10, and the average monthly number of days with fog does not exceed 2. An exception is the city of Buyukdere, where on average 39 days with fog are observed per year; The average monthly number of days with fog here is mainly 3-5.

In the described region, radiation fogs are observed more often than advective fogs. Radiation fogs are short-lived and form mainly at night and in the morning; advective fogs, on the contrary, persist for 2-3, sometimes 5-6 days and spread over long distances.

Visibility in the described area, most often 5 miles or more, its repeatability throughout the year is 80-100%. The yearly frequency of visibility less than 2 miles is less than 4%.

Radar observability. In this area, normal radar observability prevails throughout the year.

Cloudiness and precipitation. The greatest cloudiness is observed everywhere in winter, and the least in summer.

cloudiness 7-10 points) in the open sea in winter is 30-40%, in summer 10-20%. The frequency of clear skies (cloudiness 0-3 points) in summer varies from 30 to 70%, in winter - from 20 to 25%.

On the coast, the average monthly cloudiness from October to May is 5-8 points, and from June to September 2-4 points. The number of cloudy days on average per year ranges from 80 to 115, and the number of clear days - from 70 to 115.

The average monthly number of cloudy days from October to May is 6-18, and from June to September does not exceed 4.

The average monthly number of clear days from October to May varies from 1 to 9, and from June to September - from 9 to 24.

The amount of precipitation per year ranges from 620 to 840 mm.

The annual cycle of precipitation has well-defined rainy and dry periods. The rainy period on most of the coast is observed from November to March, when an average of 65-130 mm of precipitation falls per month. The dry period is clearly defined from May - June to August, when the average monthly precipitation does not exceed 45 mm.

The number of days with precipitation on average over most of the coast varies during the rainy period from 10 to 20 per month, and during the dry period this number does not exceed 6.

Maximum daily precipitation is 165 mm (Istanbul city, July).

Snow is rarely observed in the described area, mainly from December to March. The average number of days with him is no more than 18 per year. The average monthly number of days with snow varies from 1 to 6. The snow that falls quickly melts and very rarely lies for 3-4 days in a row.

Special meteorological phenomena.Thunderstorms are relatively rare and, as a rule, are accompanied by strong squalls and downpours. The average annual number of days with thunderstorms is generally no more than 10, only in the city of Canakkale it reaches 20.

In the open sea, the frequency of thunderstorms does not exceed 1%. On the coast, the average monthly number of days with thunderstorms during the year is less than 3.

hail It can fall in all seasons of the year, but is most often observed in autumn and winter. Hail is usually associated with the passage of thunderstorms, and in most cases hail is accompanied by strong winds from the N and NW.

Refraction and mirages in the described area are often observed.

HYDROLOGICAL CHARACTERISTICS. The hydrological regime of the Sea of Marmara is determined mainly by water exchange with the Black and Mediterranean seas, climatic and physical-geographical features of the area.

Water exchange through the Bosphorus Strait causes a powerful influx of less saline Black Sea waters, which desalinize the surface layer of water in the Sea of Marmara and the Bosphorus and Dardanelles straits and create a well-defined system of surface currents in them. During water exchange between the Mediterranean and Marmara seas, the more saline and dense deep waters of the eastern part of the Mediterranean Sea enter the Sea of Marmara through the Dardanelles Strait, which are carried by the deep current into the Black Sea.

The climatic features of the area determine high water temperatures throughout the year and the predominance of evaporation over precipitation, which affect the distribution of salinity and density of water, as well as the nature of currents and vertical circulation.

The physical and geographical features of the area - the relatively short length of the sea and the large ruggedness of the coastline - have a significant impact on waves, currents and other hydrological elements.

Level fluctuations and tides. In the Sea of Marmara, tidal fluctuations in level are small and have no practical significance.

Surge level fluctuations are observed mainly in bays, bays and straits. In the Bosphorus Strait with strong winds from S, and in the Dardanelles Strait with strong winds from SW, cases of a level increase of 0.6 m relative to the average level were observed.

Currents in the described area are due to water exchange between the Black and Mediterranean seas.

The current in the Bosphorus Strait, coming from the Black Sea, is directed in a narrow strip to the S. When leaving the strait, it is divided into three powerful currents, which follow respectively WSW, SSW and SE into the Gulf of Izmit. To the west of Marmara Island, the first two currents unite and flow into the Dardanelles Strait. Anticyclonic water circulations are observed in the northern and central parts of the sea.

In the bays of the Sea of Marmara and in the bays of the Bosphorus and Dardanelles straits, anticyclonic water circulations are also formed near the European coast, and cyclonic ones are formed near the Asian coast of the straits. Along the Asian coast of the Sea of Marmara, both cyclonic and anticyclonic water circulations are observed.

In some areas along the coast, currents have directions opposite to the direction of the main current flows.

The average speed of the constant current at the entrance to the Bosphorus Strait is up to 1 knot; in the strait it increases from north to south from 1-2 to 5 knots or more. In the Sea of Marmara, at the exit from the Bosphorus Strait, the average current speed is 2-4 knots, in the central part of the sea up to 1 knot, at the northern entrance to the Dardanelles Strait 1-2 knots, in some places to the south it increases to 2-4 knots. In the coastal part of the straits, almost everywhere the current speed does not exceed 1 knot.

With strong winds from NE, the speed of currents in the described area increases; with strong winds from the SW, on the contrary, it decreases; In rare cases, winds from the SW can change the direction of the current to the opposite direction to the prevailing direction.

Wind currents are well developed in the Gulf of Izmit, especially in summer, when breezes are pronounced. With a sea breeze, the speed of the total (constant and wind) current entering the bay increases, and with a coastal breeze it decreases. The speed of the total current leaving Bay 5, on the contrary, decreases with a sea breeze and increases with a coastal breeze.

In summer, with a coastal breeze, the speed of the total current leaving the bay reaches 1.5 knots.

In some places in the described area there are whirlpools.

Excitement. In the Sea of Marmara, waves with a height of less than 0.5 m predominate throughout the year, the frequency of which varies from 60% in winter to 90% in summer.

The frequency of waves with a height of 2-4 m in winter ranges from 9 to 12%, and in summer - from 1 to 4%.

Waves higher than 4 m are rare, mainly in winter. The predominant wave period is 3 s or less. Tsunamis are possible in this area.

Tsunami- sea waves formed in the oceans (seas) under the influence of earthquakes and volcanic eruptions on the seabed or near the coast. Most often, tsunamis are caused by earthquakes measuring approximately 7 or more on a scale of 12; The foci of these earthquakes are located under the ocean floor at depths generally no more than 40 km. Tsunamis propagate from the epicenter of an earthquake at a speed of 50 to 1000 km/h and have a period of 2 to 200 minutes. The length of tsunami waves is 50-500 miles, and the height is 2-5 m, so they do not have a dangerous effect on ships located in deep sea areas. The destructive effect of a tsunami is manifested in coastal areas, especially strongly in V-shaped bays and bays that have wide entrances and gradually decrease in depth towards the shore. As they approach the shore, due to the decrease in depth, the front part of the waves becomes steeper, and their height increases and can reach 10-50 m. These waves hit the shore with enormous force, causing catastrophic destruction.

It should be noted that tsunami waves are capable of traveling long distances and causing destruction at a considerable distance from the epicenter of an earthquake.

The first sign of an approaching tsunami can be a rapid drop in ocean (sea) level and a retreat of water from the shore (in shallow areas by hundreds of meters) that is not associated with normal low tide. The water retreat time is 5-35 minutes (sometimes more), after which the first tsunami wave arrives. The retreat of the water from the shore is accompanied by an unusual silence, replacing the sound of the surf.

Tsunamis are especially dangerous for ships anchored close to the shore or moored at piers.

Timely notification and warning of ships about the danger of a tsunami is carried out by radio stations transmitting navigation and hydrometeorological messages. Having received a message about a tsunami, the ship must immediately go to sea to great depths.

Temperature, salinity and density of water.Sea surface temperature averages 7-13 °C per month in winter, 15-24 °C in summer, increasing from north to south. The maximum temperature in the Sea of Marmara is observed in August (28-30 °C).

Salinity of the surface layer of the sea varies from 16-18 ‰ at the northern entrance to the Bosphorus Strait to 26-28 ‰ at the southern entrance to the Dardanelles Strait.

Density of the surface layer of the sea. Density data is only available for October and November. During these months, the water density is 1.0160-1.0170, and in the northeastern part of the sea it ranges on average from 1.0140 to 1.0160.

Transparency and color of water.Conditional water transparency in the central part of the Sea of Marmara 23-25 m, off the coast 18-20 m. Water color in the Sea of Marmara it is bright green.

Hydrobiological information.Glow of the sea. In the described area, three types of glow are observed: sparkling, diffuse and flashing.

The sparkling glow is caused by the glow in the form of sparks and glimpses of microscopic and small marine organisms (night lights and copepods). The intensity of the sparkling glow increases under mechanical influence: waves, the passage of a ship, etc.

The sparkling glow is most often observed in the open sea, but sometimes in coastal waters.

Diffuse glow is caused by luminous marine bacteria and is a uniform glow in color and intensity over large areas of the water surface, usually greenish-blue, bluish-green, or less often white or orange. Diffuse glow is common in the coastal zone, especially in the estuary areas of rivers. It is observed throughout the year, but reaches its greatest development during the rainy period. When there is rough seas or the passage of a ship, the intensity of the glow does not change.

The flash glow is caused by large luminous marine organisms: fish, jellyfish, ctenophores, and mollusks. The glow occurs more often and more intensely in coastal waters.

Sea bloom is caused by the massive accumulation of planktonic (usually plant, but sometimes animal) organisms in the surface layer of the sea. During flowering, the transparency of the water greatly decreases and its color changes. Blooming is especially developed near the coast in desalinated areas.

Seaweed. Diatoms, pyrophytes, fucus algae, red algae (phyllophora) are common in the described area, and sea grass is found near the coast.

Woodworms. In the Sea of Marmara and the Bosphorus and Dardanelles straits, the bivalve mollusk Teredo and the wood-boring crustaceans Limnoria and Chelyura are found.

Teredo usually destroys wood from the inside; its passages are directed along the fibers, but can also bend in the most bizarre way, intertwining with each other. With significant damage, the wood turns into a spongy mass.

Limnoria usually attacks wood from the surface. Its passages are shallow (no deeper than 5 mm, occasionally 15 mm from the surface), but sometimes it eats out hollows in the piles, the so-called “cauldrons”. Limnoria, as a rule, does not tolerate muddy, stagnant, oxygen-poor water.

Chelyura is somewhat larger than Limnoria; she usually settles next to her and drills into the tree in the same way. Its passages are deeper, although it does not create “cauldrons”.

In addition to wood, limnoria and chelyura can affect the insulation of submarine cables.

Fouling of marine organisms The underwater part of ships is observed all year round, but it is most intense from May to September. Sea acorns - balanus, mussels, etc. - are common here. Fouling occurs especially intensively during long stays in ports and less intensely during the rainy period when the surface layer of water is desalinated. Fouling can disrupt the normal operation of hydroacoustic and other devices. It also leads to a loss of ship speed.

Dangerous sea animals. Poisonous stargazer and scorpion fish are found here; Their spines, covered with poisonous mucus, are dangerous. You should beware of poisonous fish when swimming, working without a diving suit, and when disembarking personnel. In some places there is a rhizostoma jellyfish, the touch of which causes severe skin irritation in people.

Atmospheric pressure, wind

General information

The conditions of the general circulation of the atmosphere are formed as a result of the interaction of pressure systems: the Azores maximum, the spur of the Asian maximum and local depressions formed over the Mediterranean Sea. The climate of the Mediterranean Sea is determined by its position in the subtropical zone and is distinguished by great specificity, which distinguishes it as an independent Mediterranean type of climate, characterized by mild wet winters and hot dry summers. In winter, a trough of low atmospheric pressure is established over the sea, which determines unstable weather with frequent storms and heavy rainfall; cold northern winds lower the air temperature. Local winds develop: the mistral in the area of the Gulf of Lion and the bora in the east of the Adriatic Sea. In summer, most of the Mediterranean Sea is covered by the crest of the Azores anticyclone, which determines the predominance of clear weather with little clouds and little precipitation. During the summer months there are dry fogs and dusty haze, blown out of Africa by the southerly sirocco wind. In the Eastern Basin, stable northern winds develop - aesia. The vast water area and tortuosity of the Mediterranean coastline create a variety of wind conditions in its area. In coastal waters there are a large number of local winds.

Lot No. 1251 NW part of the Mediterranean Sea

In October, south of the parallel 40⁰ north. lat. and to the west of the meridian of the island of Sardinia, winds from the SW and W predominate; winds from other directions are winds from the NE and N. In the rest of the waters of the western part of the Mediterranean Sea, winds from N to W most often blow.

Storms are most likely north of the 40⁰С parallel and west of the island of Sardinia (on average 1-3 times per month). In early October the weather is usually good, with occasional rain. Cloudiness increases compared to the summer months. Visibility is 10 miles or more. In general, weather conditions in the month of October in the northwestern part of the Mediterranean Sea are considered transitional from season to season. Therefore, the winds and weather in October do not have any pronounced features. The average wind speed in the described area is 3 - 6 m/s. Calms are often observed here, the frequency of occurrence per month is 15 - 35%. Storms are distributed unevenly across the area. The average annual number of days with them is 10 - 27. Storms in this area are associated mainly with the passage of cyclones.

Over most of the Tyrrhenian Sea, winds from the NW predominate in summer. Of the winds from other directions, winds from SE are most often observed. In autumn, north of parallel 41° north. lat. the prevailing winds are also from NE (up to 20-25%), and to the south of this parallel, as a rule, winds from N and NW predominate (up to 65% in total). The frequency of calms in the described area is distributed very unevenly. Average monthly number days with storms, as a rule, do not exceed 2. The predominant direction of storm winds is from NE, N and NW.

Lot No. 1248 of the Ionian Sea and the island of Sicily;

In the open sea, winds from NW and W predominate throughout the year, in addition, winds from N and SW are frequent. The wind speed in almost the entire region from November to April is higher than from May to October. From May to October, wind speed is 2-5 m/s; storms are infrequent in the described area. In the open sea, the frequency of storms does not exceed 5%. Sometimes storms are severe, even turning into hurricanes, and are accompanied by downpours. Storm winds in the open sea are observed mainly from the SW, W and NW; near the coast, their direction usually changes. There are frequent squalls, accompanied by showers and hail, during which visibility is significantly impaired. A wind similar to bora, but usually weaker than it, is known locally as “borino”. It is also observed from May to November. Sirocco - hot wind from S and SE in the warm period of the year and moderately warm in the cold period - in the western part of the described area is observed almost the whole year, but most often - from March to May. Etesia - steady wind northern directions - usually observed from mid-May to mid-September in the area of the western coast of Greece. Taranta - strong wind from the NW. Taranta can last continuously even for a day, from June to November

Lot No. 1247 Aegean Sea The autumn period is characterized by weather with a predominance of cyclones passing over the southern part of the sea, winds from SE and SW predominate, lasting up to 2-3 days, sometimes intensifying to storm force. As the cyclones move towards the island of Cyprus and further to the northeast, winds from W are observed, which are replaced by winds from NW; often reaching storm force. The average monthly wind speed in the open sea and on the islands of its central part in November is 6-7 m/s. Calms in the open sea are rare: their frequency throughout the year ranges from 2 to 10%. In the Aegean Sea, storms from N and S usually begin suddenly. Storms from S are observed only in winter; their duration rarely exceeds 1-2 days; as a rule, there is large cloudiness and a drop in pressure.

1.3 Visibility, water regime of the atmosphere

General information

Distant objects are seen worse than close ones, not only because their apparent size decreases. Even very large objects at a certain distance from the observer become difficult to distinguish due to the turbidity of the atmosphere through which they are visible. This haze is caused by light scattering in the atmosphere. It is clear that it increases with increasing aerosol impurities in the air.

For many purposes, it is very important to know at what distance the outlines of objects behind the air curtain cease to be distinguishable. This distance is called visibility range, or simply visibility. The visibility range is most often determined by eye using certain, pre-selected objects (dark against the sky), the distance to which is known. But there are also a number of photometric instruments for determining visibility. In very clean air, for example of arctic origin, the visibility range can reach hundreds of kilometers. Light scattering in such air is produced mainly by molecules of atmospheric gases. In air containing a lot of dust or condensation products, the visibility range can be reduced to several kilometers or even meters. Thus, in light fog, the visibility range is 500–1000 m, and in heavy fog or a strong sandstorm it can drop to tens or even several meters.

There are geometric, optical and meteorological visibility ranges. The geometric visual range is determined by the curvature of the Earth and the light beam and depends on the height of the observer and the observed object. Optical visibility range is the distance at which a real object, under given weather, lighting and observation conditions, is on the border of visual perception. It depends on the transparency of the atmosphere, the visual acuity of the observer, the properties of the observed object and the background against which the object is observed. All of these factors are very variable, so optical visibility range is difficult to use for practical purposes as a meteorological element.

Fogs in the described area are extremely rare. On most of the coast and islands, the average annual number of days with fog is, as a rule, no more than 3. Haze in the described area is observed more often than fog

Average monthly cloudiness ranges from 4 to 6 points from October to May. On the coast and islands, the average annual number of clear days is 120 - 150. The average annual number of cloudy days ranges from 27 to 62. Precipitation in most parts of the region averages 500 - 800 mm. The average annual number of days with precipitation varies from 56 to 87. Precipitation is showery. Snowfalls are very rare.

The absence of summer rains in the south occurs because the Northern Sea is in summer under the influence of a tropical anticyclone (an area of high barometric pressure) in the eastern part of the Atlantic Ocean, which, due to the low pressure area over the southern Sahara and the Persian Gulf, subjects the Mediterranean Sea to the dominance of dry northern winds - etesium.

With high pressure above the sea, completely calm days are also common in summer. By winter, the tropical anticyclone of the Atlantic Ocean moves somewhat to the south and at the same time, an Asian anticyclone is established to the northeast of the Mediterranean Sea. The Mediterranean Sea then occupies an intermediate region between both anticyclones and often falls under the influence of the North Atlantic cyclonic region, especially in late autumn; then cyclones appear from the Bay of Biscay, the English Channel or the German Sea and, making their way through Germany, Italy and southern Greece to Asia Minor, bring behind them stormy, squally weather, accompanied by rain and ending in clearing, with a dry north wind. Similar conditions occur in early spring. In the middle of winter, an area of high pressure often invades central Europe and causes a northerly wind again on the northern coast of the Mediterranean Sea - the mistral in southern France and the tramontana in Italy. The well-known phenomenon of bora (strong northeast wind) on the shores of the Adriatic Sea occurs under the above conditions of atmospheric pressure distribution; only local conditions, namely the special location of the mountains, contribute to the extraordinary strength of this phenomenon. At the same time, a significant reserve of heat in the water column of the Mediterranean Sea causes a slightly reduced pressure above it and the source of a period of winter rains in the more southern regions of the sea. The dominance of northern winds, bringing dry air, explains to us why on the Mediterranean coast the summer heat is not as painful as in other coastal countries. In particular, the climate of different places in the Mediterranean Sea depends a lot on local conditions, and these latter, due to the extreme diversity of the terrain profile, are so different that one can often find nearby climates that differ significantly from the typical Mediterranean

Absolute and relative humidity

Absolute humidity is the amount of moisture contained in one cubic meter of air. Due to its small value, it is usually measured in g/m³. But due to the fact that at a certain air temperature the air can only contain a maximum maximum amount of moisture (with increasing temperature this maximum possible amount of moisture increases, with decreasing air temperature the maximum possible amount of moisture decreases) the concept of relative humidity was introduced

Relative humidity is the ratio of the partial pressure of water vapor in a gas (primarily in air) to the equilibrium pressure of saturated vapor at a given temperature.

An equivalent definition is the ratio of the mass fraction of water vapor in the air to the maximum possible at a given temperature. Measured as a percentage and determined by the formula:

where: relative humidity of the mixture (air) in question; - partial pressure of water vapor in the mixture; - equilibrium pressure of saturated vapor.

The saturated vapor pressure of water increases greatly with increasing temperature. Therefore, with isobaric (that is, at constant pressure) cooling of air with a constant vapor concentration, a moment comes (dew point) when the vapor is saturated. In this case, the “extra” steam condenses in the form of fog or ice crystals. The processes of saturation and condensation of water vapor play a huge role in atmospheric physics: the processes of cloud formation and the formation of atmospheric fronts are largely determined by the processes of saturation and condensation; the heat released during the condensation of atmospheric water vapor provides the energy mechanism for the emergence and development of tropical cyclones (hurricanes).

Evaporation from the surface of the Mediterranean Sea reaches 1250 mm per year (3130 km3). Relative air humidity varies from 50-65% in summer to 65-80% in winter. Cloudiness in summer is 0-3 points, in winter about 6 points. The average annual precipitation is 400 mm (about 1000 km3), it varies from 1100-1300 mm in the north-west. up to 50-100 mm in the south-east, minimum in July - August, maximum in December. Characteristic are mirages, which are often observed in the Strait of Messina (the so-called Fata Morgana).

Lot No. 1250 of the Tyrrhenian and Ligurian seas and the islands of Sardinia and Corsica;

Cloudiness and precipitation:

The highest cloudiness values are observed in the north of the region, where the average monthly cloudiness in autumn is 3-5 points.

In autumn, in the southern regions there are on average up to 25 clear days per month, and in the northern regions - no more than 15.

The most precipitation falls on the east coast: the average annual amount is 800-1450 mm.

In the open sea, visibility of more than 10 miles prevails throughout the year, and in the warm season the frequency of such visibility is greater than in other seasons. Visibility increases in the spring, and visibility of more than 5 miles prevails throughout the summer.

Relative air humidity has a relatively well-defined annual variation. In most places, the highest humidity of 70-80% is observed from December to February, and the lowest 55-65% is observed in July and August.

Lot No. 1248 of the Ionian Sea and the island of Sicily

Cloudiness and precipitation:

The average monthly cloudiness in the described area varies mainly from 4 to 6 points from October to May. In May, the frequency of clear skies increases to 55-60%, and cloudy skies decreases to 20-25%.

Precipitation in most parts of the region averages 500-800 mm per year.

Visibility:

In a significant part of the area, visibility is 10 miles and more, with a frequency of 60-85% throughout the year. In the coastal zone and on the islands in some months it is 30-55%. Visibility frequency for 5 to 10 miles in most areas ranges from 10 to 35%, and in the coastal zone and on the islands it can reach 40-70%. Winds have a significant impact on visibility. So, during sirocco, visibility decreases sharply (sometimes to 0.5 miles or less), and during bora, on the contrary, it increases (up to 10 miles or more).

Relative humidity in most places averages 50-80%. The diurnal variation of relative humidity is pronounced, especially from May to November.

Lot No. 1247 Aegean Sea

Cloudiness and precipitation:

The greatest cloudiness in the Aegean Sea region is observed in the cold season. In the open part of the sea from October to April, cloudy (8-10 points) and clear (0-2 points) skies are equally likely. The frequency of both is 20-40%. Over the coast of the Aegean Sea from October to May, average monthly cloudiness of 4-6, in some places 7-8 points prevails. From October to May, the average monthly number of clear and cloudy days is almost the same and averages on 3-10. Visibility is good, so in the open part of the Aegean Sea the frequency of visibility of 5 miles or more is 90-95%, and the frequency of visibility less than 5 miles is no more than 5-10%. There is also heavy cloudiness in the Aegean Sea area up to 8-10 points.