* Astronomy

 Springtails, mites, worms and plant life could help solve the mystery of Antarcticas glacial history according to new research published in the journal Science this week.
Scientists from British Antarctic Survey (BAS) and Massey University New Zealand report that of the evolutionary history of Antarcticas terrestrial plant and animal life does not reconcile with current reconstructions of past glacial ice extent going back more than 23 million years.
In todays warm period less than 1 percent of Antarctica is ice-free. It has been assumed that during ice ages there was insufficient ice-free land for Antarctic plant and animal species to survive and evolve. However scientists report that an exceptional long-term evolutionary persistence, isolation, and a striking capability to survive global climate change, appear to be the norm rather than the exception for the terrestrial world.

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Disasters resembling the biblical Deluge often happened in Eurasia when glaciers occupied more space than they do now. In the north, the glacier served as a natural dam for Siberian rivers, and gigantic lakes were formed in northern Asia. In the mountains, glaciers formed dammed basins, which periodically burst and flooded vast territories. Huge water and mud flows rushed out at the speed of 20 meters per second.
Researchers of the Irkutsk State University and Institutes of the Earths Crust and Geochemistry (Siberian Branch, Russian Academy of Sciences) have recently discovered traces of a catastrophic hydrobreaking in the middle flow of the Onon river, in Tchasuchey deep (Transbaikalia). They made the discovery having investigated the relief of this area with the help of GoogleEarth, so anyone can look at evidence of the biblical-scale flood by typing barun torey (Barun Torey lake in the Chita Region) in the search line and by scrutinising the locality stretching towards the north-west of the water body approximately through to Tchasuchey.


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The point is in the relief of Tchasuchey deep - hills, mounds and ridges, shallow gullies and lakes in the shallow gullies are oriented from the north-west to south-east in that region. Linearly oriented ridge and shallow gullies system is the sign that once a water flow used to rush here. At the northern boundary of the deep, the lakes are big, but within its boundaries they are shallow. The majority of the lakes are oval and round, but few having an elongated shape are pulled out strictly in the direction from the north-west towards the south-east.
Geologists have been debating so far about the origin of ridges and mounds oriented in one direction if they are of aeolian origin (or wind origin, when the wind sweeps dunes together), or of fluvial origin when the same is done by running water. The Irkutsk researchers believe that a catastrophic debacle of a gigantic pond took place there, probably this is connected with Selengin Lake that existed in former times and occupied a major part of mainland towards the east of Baikal. The fact that the shallow gully zones alternate with the mound zones is to the credit of the above hypothesis. Hills and ridges prevail in the middle part of Tchasuchey deep, but in the north and in the south, near Barun Torey Lake, shallow gullies and deeps are predominant.

Such geological structures continue up to Harbin and Changchun in China, slightly turning to the north. Judging by the relief in the region of China, it is apparent that the flow broke down into several smaller ones.
It is interesting to note that positive forms of the relief are similar to baire hillocks in the Caspian Sea region. The same parallel chains of hills consisting of sand and clay stretch in latitudinal direction along Manych shallow gully, on the spot of hypothetical strait between the Caspian and the Black Sea. They were first described by C. Baire and are called after him. Similar formations also exist in Western Siberia where water inrush went from the east to the west. So, it means that the Deluges were not infrequent during the glaciation era.

During the last Ice Age, the ice dammed enormous lakes in Russia. The drainage system was reversed several times and the rivers flowed southwards. A group of geologists is now investigating what took place when the ice melted and the lakes released huge volumes of fresh water into the Arctic Ocean.

The ice-dammed lakes in Russia were larger than the largest lakes we know today. The entire drainage system in Russia has been reversed several times during the past 130 000 years. The heavy ice cap covering the land area in the north dammed up lakes and forced the large rivers, the Dvina, Mezen, Pechora and Vychegda, to flow southwards to the Caspian Sea, the Black Sea and on to the Mediterranean - Eiliv Larsen, a geologist at the Geological Survey of Norway (NGU), tells me.

He is in charge of the important SciencePub International Polar Year project that is studying natural climate changes in the Arctic and the ways in which man has adapted to them.

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 Continental glaciers originating at both poles reached their farthest extent about 20,000 years ago, marking a time known as the Last Glacial Maximum.
Comparisons of ice cores from Greenland and Antarctica show that as these glaciers melted, warming occurred in asynchronous stages at the poles. While many northern hemisphere climate records match ice core records from Greenland, few southern hemisphere records exist to compare with ice core data from Antarctica.
Calvo et al. analyse a marine core collected off South Australia and find that it contains detailed signatures of surface temperatures of waters that washed over it since the glacial maximum.
Data from this core match well with Antarctic ice cores and paleoclimate records from the Australian continent, showing no signature of the Younger Dryas, a cooling event known to have occurred in the Northern Hemisphere about 13,000 years ago.
The new core data also reveal a progressive drop in sea surface temperatures over the last 6,500 years, an observation not seen before for the Australian region.

Title: Antarctic deglacial pattern in a 30 kyr record of sea surface temperature offshore South Australia
Authors: Eva Calvo: Institut de Ciències den Mar, Consejo Superior de Investigaciones Científicas, Barcelona, Spain;
Carles Pelejero: Institució Catalana de Recerca i Estudis Avançats and Institut de Ciències den Mar, Consejo Superior de Investigaciones Científicas, Barcelona, Spain;
Patrick De Deckker: Department of Earth and Marine Sciences, The Australian National University, Canberra, Australia;
Graham A. Logan: Petroleum and Marine Division, Geoscience Australia, Canberra, Australia.
Source: Geophysical Research Letters (GRL) paper 10.1029/2007GL029937, 2007