Under the Ice Sheet

Under the former Larsen ice shelf east of the Antarctic Peninsula, deep-sea sea cucumbers and stalked feather stars were ubiquitously found in shallow waters. These animals usually inhabit far greater water depths.

The main aim of the current Polarstern expedition to Antarctica is the investigation of marine ecosystems under the former Larsen ice shelf. This "white spot" with regard to biodiversity research gave rise to the following questions: What kind of life actually existed under the former floating ice shelf which was up to several hundreds of meters thick? What are the prospects for the future after the collapse of the ice shelf? Obviously, prosperous life did not exist in the area where the Larsen B ice shelf broke off three years ago. This is surprising since Antarctica's seafloor communities are known for their rich assemblages of sessile sponges, cnidarians and moss animals. Instead, underwater video footage and catches of towed sampling gear revealed the dominance of typical deep-sea animals and corresponding life forms.

Here, sea cucumbers and stalked feather stars are the main representatives. These deep-sea inhabitants belong to a group called echinoderms. Until now, stalked feather stars have only been found sporadically and then only below 800m water depths in this sector of Antarctica. But locally in the Larsen B region, they occurred rather frequently at depths of merely 200m. "During my nine expeditions to Antarctica, the only time I have seen the two most abundant species of sea cucumbers was below the far bigger Filchner-Ronne ice shelf further south." This second encounter brought back chief scientist Julian Gutt's memories of his first trip to Antarctica and his PhD thesis 21 years ago. Preliminary results show that a unique macrofauna exists in conjunction with the ice shelf. The sea cucumber Elpidia is probably the most prominent deep-sea animal but is also known to occur in shallow Arctic waters. Maybe this is the reason why this animal is aptly named glacialis (icy) especially with regard to our confirmatory findings on the opposite pole – Antarctica.

This species, its bigger "sister" Scotoplanes globosa and other relatives according to their feeding mode are referred to as grazers. Myriads of single-celled algae that sink down to the seafloor are literally grazed by herds of sea cucumbers. The oceanographer Enrique Isla is excited about further processing the collected data back in the Marine Sciences Institute (ICM) in Barcelona. "Our measurements of environmental parameters of the sediment and the water column will contribute to answer the question, why there are such similarities between habitat use of the deep-sea and below the former ice shelf." Scientists on this expedition will meet again in autumn in Barcelona to work on a synthesis of various results combining the different aspects of ecosystem components. This workshop will be hosted by the ICM and is supported by the Census of Antarctic Marine Life (CAML). Marine ecologist Julian Gutt is looking to the future: "The minute we have a better understanding of how ecosystems under the ice shelf work we might dare to put forward prognoses how biodiversity on the seafloor changes with respect to ongoing atmospheric warming".

*** This article was taken from http://www.ocean.com/resource.asp?locationid=1&resourceid=6922&ProdId=2866&CatId=1&TabID=&SubTabID=

10 Interesting Ocean Facts!!

1. Mount Everest (the highest point on the Earth's surface 5.49 miles) is more than 1 mile shorter than the Challenger Deep (the deepest point in the ocean at 6.86 miles).

2. Water pressure at the deepest point in the ocean is more than 8 tons per square inch, the equivalent of one person trying to hold 50 jumbo jets.

3. The worlds oceans contain nearly 20 million tons of gold. If all the gold suspended in the world's seawater were mined, each person on Earth could have about 9 pounds of gold.

4. The Great Barrier Reef, measuring 1,243 miles, is the largest living structure on Earth. It can be seen from the Moon.

5. By 2010, 80 per cent of people will live within 60 miles of the coast.

6. The total length of the world's coastlines is about 315,000 miles, enough to circle the Equator 12 times.

7. If all the world's ice melted, the oceans would rise 200 ft (66 mtr). 10,000 years ago the ocean level was about 330 ft (110 mtr) lower than it is now.

8. 90% of all volcanic activity on Earth occurs in the ocean. The largest known concentration of active volcanoes (approximately 1,133) on the sea floor is located in the South Pacific.

9. Antarctica has as much ice as the Atlantic Ocean has water.

10. Some scientists estimate that the oceans contain as much as 50 quadrillion tons (50 million billion tons=50,000,000,000,000,000) of dissolved solids. If the salt in the ocean could be removed and spread evenly over the Earth’s land surface it would form a layer more than 500 feet (166 m) thick, about the height of a 40-story office building.



*I found these facts at http://www.savethesea.org/STS%20ocean_facts.htm along with many others, but I posted these 10 because they were the ones that sparked my interest the most!

Dead Sea Plight Spurs Bike Rally

January 09, 2007 — By Associated Press
JERUSALEM -- Several hundred cyclists are expected to take part in a ride around the Dead Sea in Israel, according to the Israeli Ministry of Tourism.
The Jan. 27 event is designed to raise awareness of the importance of preserving the Dead Sea, which is shrinking. The sea contains the saltiest water in the world at the lowest point on Earth, about 1,200 feet below sea level, and its water levels have fallen about three feet a year in the past 20 years.
In December, a Jordanian official announced that a study is now under way to look at the environmental and social consequences of building a canal to transfer water from the Red Sea to the Dead Sea.
Geological experts warn that the Dead Sea will disappear in 50 years if current trends persist. Registration details for the bike rally are at http://www.zimuk.co.il/event_2.asp?event_id19&langeng.
Source: Associated Press
http://www.enn.com/today.html?id=11987



Its frightining to think that the Dead sea will disappear in the next 50 years if we continue as we are right now. With the advancements in technology, and the increases in pollution and global warming its very possible that the end of the dead sea will come sooner than predicted! I think its really important that we read more articles like this and educate people on this subject, because the majority of people probably dont realize how serious this issue is.
-Kathryn