. Earth Science News .

Satellites detect abundance of fresh water in the Arctic
by Staff Writers
Paris (ESA) Jan 24, 2012

The Beaufort Gyre is a great clockwise ocean circulation in the western Arctic Ocean. Accelerated by strong Arctic winds, the sea surface bulges upwards. Measurements from ESA's ERS and Envisat missions show that, since 2002, the surface has risen by about 15 cm and the volume of fresh water has swollen by approximately 8000 cubic km - around 10% of all the fresh water in the Arctic Ocean. Credits: CPOM/UCL/ESA/Planetary Visions.

ESA satellites show that a large dome of fresh water has been building up in the Arctic Ocean over the last 15 years. A change in wind direction could cause the water to spill into the north Atlantic, cooling Europe.

The results are remarkable: since 2002, the sea surface in the studied area has risen by about 15 cm, and the volume of fresh water has increased by some 8000 cubic km - around 10% of all the fresh water in the Arctic Ocean.

Researchers from the Centre for Polar Observation and Modelling (CPOM) at University College London and the UK's National Oceanography Centre used data from ESA's ERS-2 and Envisat satellites to measure sea-surface height over the western Arctic from 1995 to 2010.

The results were published yesterday in the online version of the scientific journal, Nature Geoscience.

The scientists conclude that the dome could be a result of strong Arctic winds accelerating a large ocean circulation known as the Beaufort Gyre, causing the sea surface to bulge.

A change in the direction of the wind would cause the fresh water to spill into the rest of the Arctic Ocean and even reach the north Atlantic.

This could slow a key ocean current, stemming from the Gulf Stream, and subsequently cool Europe.

This current keeps the continent relatively mild compared to other areas at similar latitudes.

"When we looked at our data on a year-to-year basis, we noticed that the changes in the sea surface height did not always follow what the wind was doing, so we thought about reasons why this might happen," said Katharine Giles, CPOM research fellow and lead author of the study.

"One idea is that sea ice forms a barrier between the atmosphere and the ocean. So as the sea ice cover changes, the effect of the wind on the ocean might also change.

"Our next step is to look into how changes in the sea ice cover might affect the coupling between the atmosphere and the ocean in more detail to see if we can confirm this idea."

Sea ice can be measured by different types of satellite data. Radar altimeters on satellites such as the two used in the study, Envisat and ERS-2, can be particularly useful when observing inaccessible areas like the Arctic.

Envisat, the largest Earth observation satellite ever built, will mark 10 years in orbit in March.

ERS-2 was retired in July 2011, but 20 years of data from it and predecessor ERS-1 on oceans, land, ice and atmosphere will continue to be used by scientists for years to come.

"We were able to produce the Beaufort Gyre results thanks to the overlap of the ERS-2 and Envisat missions and long-term satellite data availability," said Seymour Laxon, director of CPOM and co-author of the paper.

ESA will continue to monitor the Arctic with the upcoming Sentinel series of Earth-observing satellites for Europe's Global Monitoring for Environment and Security (GMES) programme.

Later this year, the first results of seasonal changes in sea-ice thickness from data acquired by ESA's CryoSat-2 satellite will be presented.

Related Links
Centre for Polar Observation and Modelling
National Oceanography Centre
Beyond the Ice Age

Get Our Free Newsletters Via Email
Buy Advertising Editorial Enquiries


. Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

Alaskan farewell to Russian tanker after fuel run
Nome, Alaska (AFP) Jan 21, 2012
A Russian tanker's crew headed for home Saturday - warmed by a pizza-and-beer sendoff - after delivering fuel in a dramatic winter operation helped by a US ice-breaker ship. Locals in Nome, on Alaska's western coast across the Bering Sea from the Russian Far East, voiced gratitude for the delivery to their 3,500-strong community, which is ice-locked for months over the winter. "I am so ... read more

Disaster Communications Terminals Deployed In South Sudan

TEPCO uses camera to survey Fukushima reactor

Disasters cost $366 billion in 2011: UN

Simulating firefighting operations on a PC

Quantum physics enables perfectly secure cloud computing

Dutch court rules in Apple/Samsung fight

RIM to focus more on consumer market: new CEO

Metadynamics technique offers insight into mineral growth and dissolution

Asia loses its taste for shark fin

Stranded baby seals concern Dutch rescuers

Broadcast study of ocean acidification to date helps scientists evaluate effects on marine life

Rich Asians threaten high-value fish: experts

Satellites detect abundance of fresh water in the Arctic

Alaskan farewell to Russian tanker after fuel run

Russian ship leaves after ice-bound Alaska fuel run

US, Russia to conduct joint Antarctica inspection

Study shines light on ways to cut costs for greenhouse growers

Farming is key to meeting environmental challenge: FAO chief

Sweeten up your profits with the right hybrid

Science to help rice growers affected by Japan's tsunami

Waiting for Death Valley's Big Bang

Tropical cyclone hits Mozambique, 12 dead: report

Japan and New Zealand were hit hardest by earthquakes

New floods hit northeastern Australia

Former colonial soldiers in Mozambique hope for pensions

Nigeria police fire tear gas at Lagos protest

Ethiopia: Thousands driven out in land grab

Sudan rebels say key govt outpost taken

The price of your soul: How the brain decides whether to 'sell out'

Penn Researchers Help Solve Questions About Ethiopians' High-Altitude Adaptations

Babies with three parents a possibility

Sitting pretty: bum's the word in Japan security


The content herein, unless otherwise known to be public domain, are Copyright 1995-2012 - Space Media Network. AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement