Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Earth from Space: unique Arctic landscape surveyed by Proba

08.08.2005



This Proba image shows the region around Samoylov Island, located within the Lena River Delta on the Laptev Sea coast of Northern Siberia. The small pear-shaped island of Samoylov in the lower middle of the image is one of the Delta’s more than 1 500 individual islands.

The Lena Delta, covering an area of about 32 000 square kilometres, is a haven for Arctic wildlife that transforms for five months each summer from frozen tundra to fertile wetlands. The Delta is located at the end of the 4400-km-long course of the Lena River, one of the longest rivers in the world. It is an important breeding ground for many migratory birds and supports diverse populations of fish and several marine mammals.
The largest Delta in the Arctic, the Lena Delta is a complex landscape that has evolved over thousands of years. The Holocene (the geological era extending back from the present to the last 10 000 years) Delta incorporates parts of an older accumulation plain, dating as far back as the mid-to-late Pleistocene Era. Samoylov Island is located in the central southern part of the Lena Delta, close to the Delta apex. Covering an area of 1200 hectares, it is representative of the active and the Holocene part of the Delta, estimated to back about 7000 years.


Various geomorphological levels can be distinguished in the image. The highest terraces in the image are determined by typical wet ice-wedge polygonal tundra with numerous ponds and small lakes, presenting a Mid Holocene deltaic accumulation surface of frozen fluvial permafrost deposits (dark green colours). Two lower levels are formed by Late Holocene fluvial processes (light green colours) and by recent shallow and very active sandbars (whitish colours).

All terraces undergo heavy changes in terms of river bank erosion, island migration or thermal erosion. Another interesting feature is the presence of river ice on some sandbanks in the lower right of the scene, which remained from the spring river ice break-up approximately two weeks earlier.

Around 14% of worldwide carbon is stored in permafrost soils and sediments, and scientific interest is growing in the role of tundra environments in the carbon cycle. In particular tundra wetlands like the Lena Delta are considered major contributors to the global carbon balance, and anticipated to be highly sensitive to climate change.

German-Russian research activity has been ongoing in the Lena Delta in the last few years, focusing on biology, soil sciences, ecology, paleo-environmental investigations and modern environmental change. The German Alfred Wegener Institute for Polar and Marine Research together with the Russian Lena Delta Reserve has placed an ecological station on Samoylov Island, and is evaluating whether to site a permanent environmental observatory there.

In order to better quantify carbon budgets in the vast Lena Delta tundra wetlands, Earth Observation is being used by researchers to upscale local field measurements, with Proba images helping to validate tundra surface and vegetation unit classification based on Landsat-7 data.

This image was acquired on 5 July 2005 by the Compact High Resolution Imaging Spectrometer (CHRIS). Built by UK-based Sira Technology, CHRIS is the main payload on ESA’s Proba microsatellite, designed to acquire hyperspectral images with a spatial resolution of 18 metres across an area of 14 kilometres.

The size of a washing machine, Proba was originally launched in 2001 as a technology demonstrator, but is now operated as an ESA Earth Observation Third Party Mission.

Mariangela D’Acunto | EurekAlert!
Further information:
http://www.esa.int

More articles from Earth Sciences:

nachricht NASA finds newly formed tropical storm lan over open waters
17.10.2017 | NASA/Goddard Space Flight Center

nachricht The melting ice makes the sea around Greenland less saline
16.10.2017 | Aarhus University

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Ocean atmosphere rife with microbes

17.10.2017 | Life Sciences

Neutrons observe vitamin B6-dependent enzyme activity useful for drug development

17.10.2017 | Life Sciences

NASA finds newly formed tropical storm lan over open waters

17.10.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>