Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Arctic sea ice annual freeze-up underway

After reaching the second-lowest extent ever recorded last month, sea ice in the Arctic has begun to refreeze in the face of autumn temperatures, closing both the Northern Sea Route and the direct route through the Northwest Passage.

This year marked the first time since satellite measurements began in the 1970s that the Northern Sea Route, also known as the Northeast Passage, and the Northwest Passage were both open at the same time for a few weeks.

"NIC analysis of ESA’s Envisat and other satellite datasets indicated that the Northern Sea Route opened when a path through the Vilkitski Strait finally cleared by 5 September," NIC Chief Scientist Dr Pablo Clemente-Colón said via email from aboard the US Coast Guard icebreaker Healy in the Arctic, where he is conducting joint mapping operations with the Canadian Coast Guard.

"This is the first time in our charting records that both historic passages opened up in the same year," Clemente-Colón said. "Both of the routes appeared as closed by 22 September."

The Northwest Passage’s most direct route, a long-sought shortcut from Europe to Asia through the Canadian Arctic that has been historically impassable, opened up for the second consecutive time this year.

"As early as 18 August 2008 the Northwest Passage began appearing navigable in the US National Ice Center (NIC) analysis of Envisat Advanced Synthetic Aperture Radar (ASAR) data although we were cautious in announcing it as a significant amount of ice was still prevalent," Clemente-Colón said.

The indirect, more southerly route – called the Amundsen Northwest Passage – opened up in July 2008, and according to ASAR images is about to close in the coming days.

The Northern Sea Route extends from the Norwegian Sea, along the Arctic coast of Asia and through the Bering Sea to the Pacific Ocean, while the Northwest Passage runs along the north coast of the North American continent.

Each year, the Arctic Ocean experiences the formation and then melting of vast amounts of ice that floats on the sea surface, but the rate of overall loss has accelerated.

During the last 30 years, satellites that have been observing the Arctic have witnessed reductions in the minimum ice extent at the end of summer from around 8 million km² in the early 1980s to the historic minimum of less than 4.24 million km² in 2007, as observed by Envisat.

The fact that this year’s minimum extent, which was well below the long-term average, did not break last year’s record does not signify a recovery.

"Although last year’s summer sea ice minimum extent record was not broken, a record amount of the thickest multiyear sea ice was actually lost this season impacting the thickness of the sea ice presently found around the North Pole region and setting the stage for more minimum or near-minimum records in upcoming years," Clemente-Colón said.

The Arctic is one of the most inaccessible regions on Earth and is prone to long periods of bad weather and extended darkness, so obtaining measurements of sea ice was difficult before the advent of satellites.

Radar instruments aboard Earth observation satellites, such as Envisat’s ASAR sensor, are particularly suited for monitoring Polar Regions because they are able to acquire images through clouds and darkness.

ESA has been providing satellite data on the cryosphere for more than 20 years. The agency is currently contributing to the International Polar Year 2007-2008, one of the most ambitious coordinated science programmes ever undertaken in the Arctic and Antarctic.

Further exploitation of data collected over the Arctic since 1991 is part of an ESA Initiative on Climate Change that will be proposed to the ESA Member States at its Ministerial Conference in November 2008. The proposal aims to ensure delivery of appropriate information on climate variables derived from satellites.

In 2009, ESA will make another significant contribution research into the cryosphere with the launch of CryoSat-2. The observations made over the three-year lifetime of the mission will provide conclusive evidence on the rates at which ice thickness and cover is diminishing.

Mariangela D'Acunto | alfa
Further information:

Further reports about: Arctic Climate change CryoSat-2 ENVISAT ESA Northwest Passage Polar Day SEA cryosphere satellite data sea ice

More articles from Earth Sciences:

nachricht Receding glaciers in Bolivia leave communities at risk
20.10.2016 | European Geosciences Union

nachricht UM researchers study vast carbon residue of ocean life
19.10.2016 | University of Miami Rosenstiel School of Marine & Atmospheric Science

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>