Talk:Messinian salinity crisis

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[edit] Effects on Black Sea

Does anyone have any further information about its effect upon the Black Sea? I recently read a book by David Gibbins (Called "Atlantis") in which he proposes that the Black sea would have had a different shoreline a lower level with it being isolated by the Bosporous. Just wondered if there was any evidence of this and whether it would make a useful addition to this page?

The Black Sea doesn't get most of its water from the Mediterranean, and the closing off and reopening of the Bosphorus happened most recently thousands of years ago (not millions, as with the Strait of Gibraltar). AnonMoos 07:35, 9 July 2006 (UTC)

[edit] Factual errors

I'd just like to point out for the interested reader that there are numerous factual errors in this article. These are not really substantial to the casual reader though. It is now estimated that sealevel only dropped 1500 m [1], though some articles suggest 2000 m. Also, DSDP leg 13 did not recover evaporites beyond a small piece of halite. This evidence came later. Hopefully I will be able to come back and modify the article soon, but there are quite a few facts that I would need to verify that are currently in this article. --129.173.105.28 15:57, 14 November 2005 (UTC)

  • The Med sea level was likely at different levels at different times. At some times the Med was receiving much water from a lake called Lac Mer in the Hungary area, until the flow was cut off when the mountains of ex-Yugoslavia (Dinaric) arose. The buried Nile canyon found under Cairo (by deep drilling) proves at least 2400 meters depth at some times. Without the salt and silt that has accumulated, sometimes the depth was likely even deeper than if the Med dried out now. To alter a poem that Coleridge wrote: When Nile the sacred river ran / through canyons measureless to man / down to a hot dry sink. Anthony Appleyard 23:03, 10 December 2005 (UTC)

[edit] Capitalisation

Is there any reason why this is at Messinian Salinity Crisis rather than Messinian salinity crisis? Neither of the quoted references uses capital letters. --OpenToppedBus - Talk to the driver 12:17, 1 February 2006 (UTC)

OK, I decided to be bold and just move it. --OpenToppedBus - Talk to the driver 09:52, 2 February 2006 (UTC)


[edit] Fascinating

This is extremely interesting. Thanks to those who took the time to create this article. Well done...wish they taught more of this stuff in school! CoachMcGuirk 20:35, 14 April 2006 (UTC)

[edit] When did it fill back up?

  • It was not clear from the article when the basin filled back up again. 06:46, 15 January 2007 User:24.6.103.21
  • Answer inserted. Anthony Appleyard 07:36, 15 January 2007 (UTC)

[edit] Sahara expansion

I have chosen to withdraw the conjecture that evaporation from the Mediterranean has a significant effect upon the extent of the Sahara in central (latitudinal) Africa. Any effect would have been subtle, and the the area has had at most a slight influence upon human history. I have chosen instead to suggest that pre-modern civilizations in the Mediterranean basin would have been far different even had they existed. Ancient Egypt would have had a deep hot canyon that could have pushed human habitability beyond its capacity. All parts of the eastern Mediterranean would have been drier and with harsher extremes of temperature, and the economic basis of any intellectual or religious life would not have existed, and the absence of any sea to allow access over a wide area of disparate lands would have left all of them, especially the islands of the region, extremely isolated instead of connected. Paul from Michigan 03:34, 6 February 2007 (UTC)

Source citations needed. (SEWilco 06:20, 6 February 2007 (UTC))


[edit] The World Turn'd Upside Down

I use Arnold Toynbee's model of civilizations to connect physical geography to connect large-scale history to environmental shaping of human activity. All that I can do is to paraphrase Toynbee's voluminous A Study of History, a work not yet in the public domain. Toynbee suggests as a rule that civilization arises most readily at an optimal level of challenge and reward to those who live in an area. The Mediterranean basin to this day provides adequate foodstuffs in good variety to large populations, as it did in antiquity, but not without requiring some adjustments to circumstances. Farming is possible if one adjusts to the summer droughts of the region, which means that people must store enough foodstuffs to last through a long dry summer. (Egypt has the opposite situation; its floods occur in summer and they allow food production). Fishing is possible as a supplement, but the Mediterranean Sea has relatively sparse fishing, so fish must be a supplement. Trees are large but scattered, and enough variety of trees exist to allow the addition of nutritious fruits and nuts to a diet; they rarely form dense forests that must be cleared for agriculture. Ranching is possible, in contrast to nomadic herding that characterises steppes and the milder deserts; ranching requires law and record-keeping. The Mediterranean world requires trade, seafaring, record keeping, and law, clear characteristics of civilization. Literacy becomes a necessity, at least among elites.

Civilization could appear elsewhere in ancient times (east Asia and South Asia, the Yucatan Peninsula, the highlands of Mexico and Peru, Persia, and the Tigris-Euphrates valley with little or no influence from Mediterranean civilizations, but not in any world of large enclosed waterways. The Black Sea area was an adjunct to the civilizations of the Mediterranean region, and the Caspian Sea abuts steppes to the north and west and harsh desert to the east, and the Elburz Mountains cut it off from Persia. If one ignores the terrain and the climate, the Baltic Sea looks much like the Mediterranean -- but the terrain is relatively homogeneous, and until the Middle Ages it was surrounded by dense forests that had to be cleared if agriculture was to occur. Civilization appeared in the Baltic region only during the Middle Ages when large-scale forest-cutting became possible, and without doubt under the influence of Mediterranean cultures. The Great Lakes of North America (note what I call myself) also have some superficial similarity to the Mediterranean region as large bodies of water, but as in the Baltic basin the terrain is remarkably uniform. The region was populated by hunter-gatherers until modern times, when people whose culture clearly derived from Mediterranean civilizations (the Dutch, French, and English) began to clear dense forests for farmland and started exploiting the lakes as inland seas.

Toynbee suggests that conditions can soft enough for hunter-gatherers to persist indefinitely, as in the African "Great Lakes" region in which temperatures are uniform and foodstuffs are plentiful for small populations.

To be sure, the highest material and intellectual achievements reflect the refined geniuses of the likes of Euclid -- but some environments make such a person irrelevant despite his potential. I can see Euclid as one that conditions made necessary (he was as much a master of logic as of mathematics), but someone who would have been irrelevant in most places. If you are to discuss classical Greece, one recognizes that trade and foodstuff storage made record-keeping and architecture necessary, and that legal disputes and political debates that required shrewd argumentation were best made by those who had well honed their skills in formal logic before becoming lawyers and politicians, something that Euclid's Elements did very well.

Intellectual greatness as a rule requires extreme refinement of technique -- but the technique as a rule requires an economic foundation. No marble -- no Michelangelo. No patrons (for the lack of economic surpluses) -- no Michelangelo. No heritage of technique -- no Michelangelo. One can say much the same of Isaac Newton and Johann Sebastian Bach.

If the Mediterranean Sea basin had continued to be blocked off from Atlantic waters to this day, then not only would the physical world be wildly different to now, but so would the intellectual world. The classical civilizations from Egypt to Greece, Rome, and Carthage would ever have existed. Even if the ice sheets had retreated and opened the lands of northern Europe to human settlement (a dessicated Mediterranean might have made the Ice Age more severe), civilization would have formed later than otherwise in the lands around the Baltic and North Seas; Irish, English, German, Scandinavian, Polish, and Russian civilization owe much to Rome and Greece. Perhaps the Chinese and Japanese would have reached the New World instead of Europeans -- but not with any heritage of Athenian or Icelandic democracy. Perhaps the Aztecs would have successfully expanded their civilization into the temperate regions of North America... and the area around the southwestern shore of Lake Michigan would look far different from the Chicago and Milwaukee that we know, and with far-different institutions. Even the Italian Renaissance might not have occurred, as there would have been no ancient culture to exploit.

In religion? Monotheism appeared for a short time in Egypt and took deep root in Judea. Monotheism requires some intellectual sophistication, something unlikely to arise in the Levant. The absence of Abraham implies neither Moses, Jesus, nor Mohammed. Maybe we would have some fusion of Zoroastrianism and Buddhism throughout the world. Who knows?

If anything, the responsibility to prove that the world would be much the same lies upon anyone who seeks to claim that the world, materially and intellectually, would be much the same except in the areas around the Mediterranean Sea. I have my doubts that we would be having this discussion if the Mediterranean basin were permanently emptied of water; the knowledge and technology would probably not exist.

To be sure, Wikipedia has an invariable bias toward humanity for the simple reason that only members of Homo sapiens make contributions. It also has a bias toward literate, civilized persons because any remaining pre-literary and pre-technological persons make no contributions. That said, I prefer humanity to whatever low life might thrive in a saline pressure cooker utterly unsuited to humanity. --Paul from Michigan 19:00, 10 February 2007 (UTC)

yikes, that was a rant :) the best thing to do in a situation like this is to either question speculative statements, demand a source, or even remove them completely. 131.111.8.97 16:01, 12 February 2007 (UTC)
I use convection and circulation around a candle as a model for the hot Mediterranean desert causing a plume of upward air flow which draws in air across all the surrounding continents, producing rain forests all around it. Explorers from the Inca empire would have lined the Sahara rain forest cliff tops with stepped stone pyramids. (SEWilco 20:12, 12 February 2007 (UTC))

Truly, SEWilco, you must be joking, and I concede that you have a great punchline -- but poor history and science. The Incas were not a seafaring people. The heating of air upon the dried seabed would have been entirely adiabatic. Adiabatic heating is entirely reversible, and it would not lead to convectional flow of air masses. As air is changed in pressure with no change in chemical composition it becomes hotter in proportion to pressure in absolute temperature.

No evidence exists of any tropical rainforests in the Mediterranean basin at any time during the Pleistocene era (I will cite Jonathan Adams' Pleistocene Atlas when I find it) and his vegetation maps show that the northern Sahara at its moistest was "mere" grassland away from the coast and Mediterranean dry forest no more than a couple hundred kilometers away from the coast in a time in which summers were warmer and winters were cooler than now due to different points of apohelion and perihelion during the year. Thus if you take air at the freezing point of water (the pressure relates to absolute temperature in degrees Kelvin), then the temperature rises from 273°K (0°C) to 546°K (273°K), and if you reduce the pressure by a half, then the temperature goes down to 137°K or -137°C if you don't account for phase changes within the gas. In meteorology, air masses are observed to obey the perfect gas law very well.

So suppose that some cold air funnels down through the valley of the Rhone or the Po from near the glacial front of the Alps at a temperature at modern sea level of the freezing point for water, 273°K (0°C). Even without added heat from any other source, for example if the Mediterranean seabed is completely shrouded in thick clouds (which I have no cause to assume) so that the air cannot be heated by the sun or be heated by warm sun-baked rocks or water, exposed volcanic vents, or a localized greenhouse effect, an increased pressure of 25% raises the absolute temperature by 25%, or about 68°K to 68°C, which is quite unpleasantly hot for mammalian life. Proteins gelatinize at lower temperatures. That's slightly more than 150° F, which is higher than the record land temperature in modern times. Water at such a temperature would scald one. The pressurized air would warm the rocks and any water even without sunlight reaching the sea floor.

But adiabatic heating is reversible, so once some other flow of air pushes pressure-heated air out of the Mediterranean basin the air forced aside itself chills to temperatures normal for the time and place -- much chillier than they are now.

Jonathan Adams[2] has a series of maps of Europe and northern Africa that show the sorts of vegetation characteristic of various times duting the Ice Age. All times of lower seashores correlate to greater volumes of ice sheets, and all such times correspond with drier conditions throughout the Mediterranean basin. Although Adams does not treat the dessication of the Mediterranean as essential to his model, any time of lowered sea shores implies the expansion of deserts into places where deserts are not to be found now and not only into lowered sea shores. The lands to the north of the Mediterranean Sea and such islands as Corsica, Sardinia, Sicily, and Crete become dry grassland comparable to the American High Plains today. At some times the eastern part of the Mediterranean -- the Levant and most of Turkey -- basin becomes 'semidesert', which may or may not imply the disappearance of the Mediterranean Sea.

It can be safely said that when the Mediterranean Sea was dried out in whole (due to the closing of the Straits of Gibraltar) or in part (due to glacial-era lowering of sea levels), the region was always less pleasant for human life, less suitable for dense settlement characteristic of ant classical civilization, and less easily (if at all) traversible. Jonathan Adams has the great sources that I don't.

As for the rise of civiliaztion in the Mediterranean basin: we know the general timeline, and even the earliest civilization in the region (Egypt) apears after the retreat of the glaciers. The other civilizations of the Fertile Crescent (especially Judea, Phoenicia, Sumer, and Mesopotamia) appear later, as do Greece and Persia. Mesopotamia, Sumer, and Persia apparently appeared independently of Egypt, but without doubt ancient Greece, Judea, and in turn Rome and we moderns can trace our heritage of civilization more to Egypt than to either Sumer, Mesopotamia, or Persia.

Does anyone question that without a water-filled Mediterranean Sea, even without the expanded glaciers of glacial maxima, that the world would be very different, at least in its history? Even if civilization had spread to western Europe from Persia and Mesopotamia instead of from Egypt through Greece it would have been very different, and would have spread with greater difficulty without the milder climates and easy transportation that the Mediteranean provides. --Paul from Michigan 00:46, 20 February 2007 (UTC)

[edit] "If the Mediterranean hadn't reflooded"

The list of possible effects if the Mediterranean hadn't reflooded is pure speculation, with no references cited. The entire course of human history would have been altered beyond recognition, and picking a few random changes that might have occurred around its coast is completely arbitrary. I'm going to remove the whole list unless someone provides a citation. Hiding it in the "Popular culture" section (which also ought the be removed entirely, but that's another debate) is no excuse for not citing sources.James A. Stewart 01:05, 21 April 2007 (UTC)

I deleted it several times. Sink it again. (SEWilco 04:56, 21 April 2007 (UTC))
I'm referring to the items marked by "citation needed" which are speculation with no references cited. (SEWilco 05:39, 21 April 2007 (UTC))

[edit] 40 year gap

There presently is a gap of about 40 years (1920-1961) in the discovery of clues of the crisis. I think I still have one source on the topic which I'll check again. (SEWilco 18:44, 6 June 2007 (UTC))

[edit] H.G. Wells

As much as I like his novels, I think it is inappropriate that this article should have an entire (lengthy) paragraph almost solely devoted to speculations on the part of H.G. Wells before even starting to treat the subject itself. Wells was not a scientist and his thoughts on this phenomenon are indeed speculative, and as such they lack relevancy. This way we could include entire sections of similar speculative thought by lay individuals about natural phenomena in lots of other articles, which we don't. The connection with the actual Messinian Salinity Crisis is weak; Wells speculates about an event which he thought might have taken place during the last Ice Age (not the Miocene), when nothing happened that may come close to a drying up of the Mediterranean, and he thought the Mediterranean plains would have been fertile, which they obviously weren't. In my opinion, Wells' views, if they are to be mentioned, should be much less prominently featured than they are now. Iblardi 19:41, 6 June 2007 (UTC)

It's a non-fiction history book, which is why I used phrases such as "thought" and "believed". He shows that there was awareness that the basin might have dried up, and at least one clue had been noticed before 1961. (SEWilco 01:50, 7 June 2007 (UTC))

[edit] Gibraltar strait "permanently" open?

On serveral places in the article it is said that the Gibraltar strait is now permanently open. Given evidence that the Mediterranean has dried up several times in the past, is it not realistic to think it will happen again? Drhex 21:23, 30 July 2007 (UTC)

Possibly, but an open Strait of Gibraltar has been present for the last 5.odd million years, which can count as "permanent". The Messinian Crisis was only of short duration compared to that time span. Iblardi 21:45, 30 July 2007 (UTC)
Check out Pangaea Ultima. I know it's only hypothetical, as it is a projected future, but is most likely that Gibralter will close off again. It is not contested that Africa is moving north into Europe. There's an illustration at [3]. Of course, if the sea levels rise much, it may be a moot point. samwaltz 23:10, 30 July 2007 (UTC)
Sure, given the general pattern of plate tectonics in that region it is more than likely that it will happen again. Go ahead and mention it. "Permanently" in this context is only relative of course, i.e. counting from ~5 million years ago up to our present day. Iblardi 10:35, 31 July 2007 (UTC)

[edit] Pressure and temperature at the dried-up abyssal plain

I wonder about the temperature and pressure at the lowest bottom of the dried-up Mediterranean basin. Can anyone calculate it? I assume an “altitude” similar to the deepest places in the Mediterranean Sea today. Also, global temperatures where higher 5 – 6 million years ago. So present-day Spain, Portugal and Morocco might have been tropical. Could liquid water exist on the bottom of the dried-up abyssal plain? Even if it could temperatures might have been above 150°C. If so the area would have been lifeless since no known cellular mechanisms would work properly at such temperatures. In other words not even the hardiest of heat-loving bacteria would had survived.

2007-12-08 Lena Synnerholm, Märsta, Sweden. —Preceding unsigned comment added by 85.229.19.152 (talk) 17:33, 8 December 2007 (UTC)

I was probably too generalising about the climate at the time. The time span of tried-up Mediterranean episodes is 700,000 years. With an ice-age cycle of 96,000 years this equels to 7 1/3 cycle. During interglacials the climate in the regions where probaly as I described them. During ice-ages global climate might have been as today or even colder. Still, I wounder if anyone can calculate the temperature and preasure on the bottom of the dried-up abyssal plain.

2008-01-19 Lena Synnerholm, Märsta, Sweden. —Preceding unsigned comment added by 85.229.19.152 (talk) 18:21, 19 January 2008 (UTC)

[edit] "In Popular culture"

I don't see that this section refers to the Messinian salinity crisis at all - hence my removal of it. Certainly none of the works refer to the Messinian period. A list of works of fiction about the Mediterranean sea has any place in an encyclopaedia article about a specific event at a specific time. At worst, the map leads to great confusion, suggesting at first blush that the crisis may have occurred alongside neolithic man. The Dinosaur article does not have an extensive list of books about cavemen eating dinosaurs, etc. If the material must remain, it could be reduced to a passing comment that "some people have written about the Med drying out", and if absolutely necessary an article "Fictional works about the desiccation of the Mediterranean sea" could be created. But no long list please. Verisimilus T 17:08, 4 April 2008 (UTC)

Yes, it does seem to have acquired a lot of fluff which is not particularly relevant nor likely to be useful in the rest of the article. I agree with its removal. -- SEWilco (talk) 20:17, 4 April 2008 (UTC)