Did Antarctic Glacier Growth Cause Messinian Salinity Crisis (aka Mediterranean Sea Drying up) ?

An international research team led by a scientist at New Zealand's University of Otago has resolved the mystery of the processes involved in the Mediterranean Sea drying up around 5.6 million years ago.

The event, known as the Messinian Salinity Crisis (MSC), saw the Mediterranean become a 1.5km deep basin for around 270,000 years. It also left a kilometers-deep layer of salt due to seawater evaporation.

The cause of the MSC has been the subject of vigorous scientific debate, but now an international team of researchers led by Otago geologist Dr Christian Ohneiser have used a multidisciplinary approach to solve the puzzle.

link.

Did Climate Change or People do in the Mediterranean Forests?

Extinct Mediterranean forests of biblical times could return and thrive in warmer, drier future.

The Mediterranean has cradled humanity and our cities, farms, domesticated animals, and logging habits for many thousands of years. During the last 5 to 8 millennia, as people developed farming and settled in cities, the landscape has gradually changed from a thick canopy of trees to open grass and shrubs. The ghosts of Sicily's extinct evergreen forests of holm oak (Quercus ilex) and olive trees (Olea europaea) remain in the record of pollen left in the lakebed sediments. On the slightly cooler and wetter coast of Italy's Tuscany region, European silver fir (Abies alba) once mixed with holm oak and deciduous oaks (Quercus cerris and Quercus pubescens).

Many researchers believe that progressively drier conditions in the Mediterranean brought about these changes in vegetation over the past 5-8,000 years. With the accelerating warming and drying brought to the region by anthropogenic climate change, the native trees might be expected to be pushed beyond the edge of their drought and heat tolerance, never to return. Some researchers have even suggested restoring forests with non-native Eucalyptus species from Australia or Douglas fir from North America.

In the September 2015 issue of ESA Frontiers, Paul Henne and colleagues dispute the idea that a drying climate was responsible for the disappearance of Mediterranean forests. They think that frequent wildfires, logging, agriculture, and the browsing of cattle, sheep, goats and unchecked deer over the long history of human occupation have wrought the changes to the landscape.

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The Messinian Salinity Crisis may NOT Have Completely Dessicated the Mediterranean Sea

The deep record of the Messinian salinity crisis: Evidence of a non-desiccated Mediterranean Sea

Authors:

Lugli et al

Abstract:

This research is focused on a complete reexamination of the evaporite facies present in all the cores that cut through the topmost deposits of the Messinian salinity crisis lying below the floor of the Mediterranean Sea (DSDP Legs 13 and 42A, ODP Legs 107 and 161). This review suggests that the uppermost evaporite units in both western and eastern deep Mediterranean basins consist mainly of clastic (gypsrudite, gypsarenite and gypsiltite) and fully subaqueous deposits (laminar gypsum, selenite and cumulate halite) that are partially affected by burial anhydritization and tectonic-induced recrystallization. No unequivocal evidence of shallow water or even supratidal (sabkha) deposition is in evidence, suggesting that at the very last phase of the salinity crisis the Mediterranean Sea did not experience desiccation, but that deposition took place under permanent subaqueous conditions.

Simulating the Zanclean Pliocene Neogene Flood of the Mediterranean Sea

Computational fluid dynamics simulations of the Zanclean catastrophic flood of the Mediterranean (5.33 Ma)

Authors:

Periáñez et al

Abstract:

Numerical simulations of the Mediterranean Sea filling after the Messinian salinity crisis have been carried out with a two-dimensional non-linear depth-averaged hydrodynamic model. It overcomes simplifications and gross estimates of previous 0-D models. Erosion of the seabed has been implemented in the model domain. The highest erosion rates were found in the Alboran Island passage and in the eastern side of the Strait of Gibraltar. Regressive erosion, at a final stage, can account for the incision channel found in Camarinal Sill. This last limits the inflow to some 90 Sv when the cross-section in the eastern side becomes higher. Water level in the Mediterranean increases at a rate of a few meters per day. Detailed views of the induced circulation in the Mediterranean Sea have also been obtained.

Blanus mendezi: a new Miocene Neogene Mediterranean Worm Lizard

The first intact skull of a Mediterranean worm lizard has been found in Spain, according to a study published June 4, 2014 in the open-access journal PLOS ONE by Arnau Bolet from Institut Català de Paleontologia Miquel Crusafont (Universitat Autònoma de Barcelona) and colleagues.

Only isolated fragments of fossil Mediterranean worm lizards have previously been found in Europe, and currently, our limited knowledge of their evolution is mainly based on molecular studies. The worm lizard is a limbless, scaled reptile and categorized in the genus Blanus in the Mediterranean. The authors have now found the only known fossil worm lizard skull from Europe and have determined it's a new species, called Blanus mendezi. This almost complete 11.3 mm skull and vertebrae from the Middle Miocene (11.6 million years ago) is the most complete fossil of this genus.

In the study, the scientists described the fossil and integrated available molecular, paleontological, and biogeographic data to discover that both the general configuration of the skull and the teeth are in accordance with those of extant Blanus, B. mendezi, which represents the oldest record of the Western Mediterranean clade. Scientists suggest that the new species emerged after the split between the two main (Eastern and Western Mediterranean) extant groups of blanids.

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Miocene Black Sea-Pebbly Breccia Desiccation Predates the Mediterranean Messinian Salinity Crisis

Black Sea desiccation during the Messinian Salinity Crisis: Fact or fiction?

Authors:

Arjen et al

Abstract:

The late Miocene Messinian Salinity Crisis (MSC) was an extraordinary geologic event in the Mediterranean Basin marked by massive salt accumulation and presumably basin desiccation as a consequence of the reduced water exchange with the Atlantic Ocean. The discovery of a desiccation deposit in the Black Sea, the so-called Pebbly Breccia unit, was used to claim that the Black Sea also became desiccated during the MSC. Erosional features interpreted from seismic profiles of the Black Sea margin, correlated by some to the Pebbly Breccia unit, were used to support this hypothesis. However, the age of the Pebbly Breccia is poorly constrained, and its origin and relevance to the MSC subject to controversy. Here we present new biostratigraphic (dinoflagellate cyst) data from two key sedimentary successions located in a deep and a marginal setting of the Black Sea Basin. These records demonstrate that the Pebbly Breccia predates the Mediterranean water-level drop during the MSC. We argue that the presumed erosional features in the Black Sea Basin are not related to the MSC and likely represent an older Miocene event.

Evidence of a Silurian to Triassic Gondwana Origin Superfan Formation in the Eastern Mediterranean

The dispersal of the Gondwana Super-fan System in the eastern Mediterranean: New insights from detrital zircon geochronology

Authors:

Kydonakis et al

Abstract:

We report here new LA-ICPMS detrital zircon U–Pb ages of a quartzite from the autochthon of Peloponnesus (Feneos locality), southern Greece. The rock classifies as a mature quartz arenite and belongs to an original shale–sandstone succession now metamorphosed into a phyllite–quartzite unit. Zircon age clusters at 0.52–0.75, 0.85, 0.95–1.1, 1.75–2 and 2.4–3 Ga point at the Saharan Metacraton and the Transgondwanan Supermountain as contributing sources; the youngest concordant grain is 522 Ma old. Our data collectively suggest deposition during the Cambro-Ordovician in a collisional setting and are in excellent agreement with those of the virtually intact Cambro-Ordovician sandstone–shale sequences of Libya (Murzuq and Kufrah basins) and the Middle East (Israel and Jordan), interpreted to have been deposited in the Gondwana Super-fan System which draped the northern Gondwanan periphery from ~ 525 to 460 Ma. By contrast, re-evaluating the available zircon age-distribution pattern and depositional setting of an analogous sequence forming the autochthon of north-central Crete (Galinos beds) we demonstrate that it was originally deposited in a completely different setting, i.e. in an accretionary/fore-arc complex outboard of the south Laurussian active margin (Pelagonia) during the Late Carboniferous. Comparing similar Cambro-Ordovician metasiliciclastic rocks from north-eastern Crete (Sfaka paragneiss), north-central continental Greece (Vertiskos terrane), north-western Turkey (central Sakarya terrane) and the Romanian Carpathians we show that their detrital zircon distribution patterns testify to an original depositional setting similar to that of Peloponnesus (Feneos), Libya and the Middle East. Using key time-frames from previously published palaeogeographic reconstruction models we are able to trace in space and time the Palaeozoic–Early Mesozoic wondering paths of the aforementioned sequences. Thus, time- and facies-equivalent rocks presently cropping out in the eastern Mediterranean share a common provenance from the Gondwana Super-fan System which was diachronously dispersed between Early Silurian and Early Triassic.

Evidence the 'Sea People' of the Eastern Mediterranean Were European

Swedish archaeologists in Jordan led by Professor Peter M. Fischer from the University of Gothenburg have excavated a nearly 60-metre long well-preserved building from 1100 B.C. in the ancient settlement Tell Abu al-Kharaz. The building is from an era characterised by major migration.

New finds support the theory that groups of the so-called Sea Peoples emigrated to Tell Abu al-Kharaz. They derive from Southern or Eastern Europe and settled in the Eastern Mediterranean region all the way to the Jordan Valley.

'We have evidence that culture from present Europe is represented in Tell Abu al-Kharaz. A group of the Sea Peoples of European descent, Philistines, settled down in the city,' says Peter Fischer. 'We have, for instance, found pottery resembling corresponding items from Greece and Cyprus in terms of form and decoration, and also cylindrical loom weights for textile production that could be found in central and south-east Europe around the same time.'

Tell Abu al-Kharaz is located in the Jordan Valley close to the border to Israel and the West Bank. It most likely corresponds to the biblical city of Jabesh Gilead. The Swedish Jordan Expedition has explored the city, which was founded 3200 B.C. and lasted for almost 5 000 years. The first excavation took place in 1989 and the most recent in autumn 2013. All in all, 16 excavations have been completed.

Peter M. Fischer and his team of archaeologists and students have surveyed an urban settlement that flourished three times over the 5 000 years: around 3100-2900 B.C. (Early Bronze Age), 1600-1300 B.C. (Late Bronze Age) and 1100-700 B.C. (Iron Age). These are the local periods; in Sweden, they occurred much later.

Remarkably well-preserved stone structures have been exposed during the excavations. The finds include defensive walls, buildings and thousands of complete objects produced locally or imported from south-east Europe.

'What surprises me the most is that we have found so many objects from far away. This shows that people were very mobile already thousands of years ago,' says Fischer.

link.

What was the Carrying Capacity of Large Herbivores in the Pleistocene Quaternary Mediterranean?

Ungulate carrying capacity in Pleistocene Mediterranean ecosystems: Evidence from the Atapuerca sitesAuthors:

Rodriguez et al

Abstract:

Large herbivore carrying capacity, that is, the maximum biomass of large herbivorous mammals that an ecosystem is able to sustain for the long term, is a key factor in ecosystems trophic dynamics. The carrying capacity of Pleistocene ecosystems conditioned the survival opportunities and colonization capabilities of hominin populations in Europe. In this study, we use the amphibian and squamate record of two Early and Middle Pleistocene sites from Sierra de Atapuerca (Spain) to obtain estimates of past temperature and rainfall values. A function derived from the analysis of a wide set of recent mammalian communities is used to infer the large herbivore carrying capacity of the Atapuerca ecosystems during the Pleistocene from those climatic variables. This function provides reliable estimates of large herbivore carrying capacity in open environments but not in forest communities. The results presented in this study indicate that carrying capacity was higher at Atapuerca during most of the sequence than in the present. Our data also suggest that in most Mediterranean ecosystems, large herbivore biomass is currently below the carrying capacity of the environment due to the relatively low diversity of the large herbivore guild in most recent communities. Although the carrying capacity was high at Atapuerca in the periods the area was occupied by humans, it was also high in other periods for which no evidence of human presence has been recorded. Thus, the relationship between human occupation of the territory and carrying capacity does not appear to be simple.

Extinction of Sirenia of Europe and North Africa

The disappearance of the European/North African Sirenia (Mammalia)

Authors:

1. Gonçalo Prista (a)
2. Mário Estevens (c)
3. Rui Agostinho (d)
4. Mário Cachão (a, b)

Affiliations:

a. Centre of Geology of the University of Lisbon, Campo Grande, 1749-016 Lisbon, Portugal

b. Faculty of Sciences of the University of Lisbon, Geology Department, Campo Grande, 1749-016 Lisbon, Portugal

c. Almada City Council, Departamento de Estratégia e Gestão Ambiental Sustentável Ecoteca de Almada - Casa Municipal do Ambiente R. Bernardo Francisco da Costa, nº 40 e nº 42 2800-029 Almada, Portugal

d. Faculty of Sciences of the University of Lisbon, Physics Department, Campo Grande, 1749-016 Lisbon, Portugal

Abstract:

Sirenia inhabited the coastal waters of Europe and North Africa from the Eocene until the end of the Pliocene. They are the only herbivorous marine mammals, and their presence in the European/North African realm is supported by almost 400 fossil records. Their dependence on seagrass, as well as their ecological needs, limited their capability to adapt to the climate changes that occurred during the Cenozoic. Their disappearance from European and Mediterranean shores occurred in two different steps: 1) the European Atlantic extinction, related to global cooling and fragmentation of the seagrass meadows, which greatly reduced sirenia habitats and resources; 2) their disappearance from the Mediterranean, linked not to declining resources but to the onset of continental glaciations in the northern hemisphere.

Anaerobic Metazoans!!!

Living exclusively oxygen-free was thought to be a lifestyle open only to viruses and single-celled microorganisms. A group of Italian and Danish researchers has now found three species of multicellular animal, or metazoan, that apparently spend their entire lives in oxygen-starved waters in a basin at the bottom of the Mediterranean Sea.

The discovery "opens a whole new realm to metazoans that we thought was off limits", says Lisa Levin, a biological oceanographer at Scripps Institution of Oceanography in La Jolla, California.

Roberto Danovaro from the Polytechnic University of Marche in Ancona, Italy, and his colleagues pulled up the animals during three research cruises off the south coast of Greece. The species, which have not yet been named, belong to a phylum of tiny bottom-dwellers called Loricifera. Measuring less than 1 millimetre long, they live at a depth of more than 3,000 metres in the anoxic sediments of the Atalante basin, a place so little explored that Danovaro likens his team's sampling to "going to the Moon to collect rocks".

Researchers have previously found multicellular animals living in anoxic environments, but Danovaro says that it was never clear whether those animals were permanent residents. The new loriciferans, which he and his team reported this week (R. Danovaro et al. BMC Biol. doi:10.1186/1741-7007-8-30; 2010), seem to "reproduce and live all their life in anoxic conditions", he says.

The researchers identified an adaptation that helps these loriciferans to survive in their environment. Instead of mitochondria, which rely on oxygen, the creatures have organelles that resemble hydrogenosomes, which some single-celled organisms use to produce energy-storing molecules anaerobically.

Just.

Plain.

*WOW*

An Ectothermic Mammal Found?

A prehistoric goat survived for millennia on a resource-poor island by living like a reptile—changing its growth rate and metabolism to match the available food supply, according to a new study of the animal's bones.

The discovery marks the first time scientists have seen this cold-blooded survival strategy in mammals.

[...]

Fossils of the ancient goat, called Myotragus, were first found on Majorca in the early 1900s. The bones show the species lived on the island for more than five million years.

[...]

But the new study, which looked at the bone histories of several Myotragus individuals, revealed that the goats may have fine-tuned their growth and metabolic rates both seasonally and during irregular times such as droughts—just like reptiles.

"This way, it burned only the energy that was available from the environment, slowing down the 'fire of life' in times when resources became scarce," Köhler said.

The lizard-like lifestyle, however, meant that Myotragus's newborns were extremely small—the sizes of large rats—and the young took years to reach adult size.

The goat also saved a lot of energy in its nervous system—among the body's most "costly" tissues—by sporting a brain only half the size of a similar-size hoofed mammal and eyes only a third as large.

The combined effect was that Myotragus was sluggish, with slow reaction times, the bone study suggests.

Like modern-day reptiles, the goats probably "saved as much energy as possible just lying around and basking in the sun," Köhler said.

"The postcranial skeleton indicates that this animal was not able to run, jump, or move fast around, and [would have been] easy prey."

Someone have a link to the paper? I'd like to see if this is really the case that the goat lost endothermy. It has been posited for crocs, but not many other animals.

Note the brain size decrease, folks.

Dust Plumes Over the Med

Precipitation Change in the Med, Iberian Peninsula

1950 vs 2006.

No difference there. No climate change at all, nuh uh.

Global Warming: Mediterranean Goes Caribbean?

Global warming could trigger hurricanes, or tropical cyclones, over the Mediterranean sea, threatening one of the world's most densely populated coastal regions, according to European scientists.

Hurricanes currently form out in the tropical Atlantic and rarely reach Europe, but a new study shows a 3 degrees Celsius (5.4 degrees Fahrenheit) rise in average temperatures could set them off in the enclosed Mediterranean in future.

"This is the first study to detect this possibility," lead researcher Miguel Angel Gaertner of the University of Castilla-La Mancha in Toledo, Spain, told Reuters on Monday.

[...]

In a paper published in the American Geophysical Union Journal, Gaertner and colleagues from the Max Planck Institute for Meteorology in Hamburg, Germany, used a range of regional climate models to assess the chance of similar events in the Mediterranean.

They found rising temperatures pointed to increasing storm intensity and, in the case of the most sensitive computer model, a likelihood of strong hurricanes.

Wow. That's interesting. AFAIK, it is the first to suggest it and that is very odd, because the temperature rise in the Med region is projected as far back as 2001 as being higher than the global average. A note of caution, while this may make sense on a certain level, this is the first paper suggesting this and only in the most extreme case. That means this is very, very speculative and until we see more papers supporting this assertion, treat this as an interesting, but not likely scenario.