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 How much biomass grows in the savannah?
16.02.2017 | Friedrich-Schiller-Universität Jena

nachricht Canadian glaciers now major contributor to sea level change, UCI study shows
15.02.2017 | University of California - Irvine

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Biocompatible 3-D tracking system has potential to improve robot-assisted surgery

17.02.2017 | Medical Engineering

Real-time MRI analysis powered by supercomputers

17.02.2017 | Medical Engineering

Antibiotic effective against drug-resistant bacteria in pediatric skin infections

17.02.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>