The next couple of weeks are critically important

Sep 14, 2011 12:43 GMT  ·  By
This is a mosaic of Envisat ASAR radar images acquired between September 9-11 over the Arctic Ocean
   This is a mosaic of Envisat ASAR radar images acquired between September 9-11 over the Arctic Ocean

According to scientists, Arctic sea ice loss rates have decreased considerably over these past few days, indicating that the lowest extent for 2011 has already been achieved. Once this happens, ices begin to grow back until they reach a maximum during the winter.

But climate scientists are not entirely convinced that the loss will stop here. They caution that there are still numerous events that can take place and influence the overall outcome. Final data on this issue will only be available in October, they added.

Taking early September as a reference point, German researchers at the University of Bremen say that this year's ice loss was even more significant than the one recorded back in 2007 – when the lowest ice extent in history was recorded at the North Pole.

Over the past few years, numerous warm winters chipped away at Arctic ices, especially the multi-year variety. While 2007 represented a turning point, setting an all-time low since satellite measurements began in 1979, 2011 isn't trailing too far behind.

Scientists with the US National Snow and Ice Data Center (NSIDC) expect total ice expanses for this year to exceed those of 2007, but they too say that nothing is set in stone just yet. The next month will be very tense for researchers, who will continue to monitor the situation closely.

“It seems to be clear that this is a further consequence of the man-made global warming with global consequence. Directly, the livelihoods of small animals, algae, fish and mammals – like polar bears and seals – are further reduced,” Bremen expert Dr Georg Heygster says.

A Japanese microwave sensor aboard the NASA Aqua satellite provided a significant portion of the data used for the study. The CryoSat spacecraft, the Soil Moisture and Ocean Salinity (SMOS) satellite and the GMES Global Monitoring for Environment and Security (GMES) probes contributed as well.

The three probes are all operated by the European Space Agency (ESA), and each of them complements the other's capabilities. Together with their American counterpart, they produce crystal clear views of the Arctic.

“Observations from space greatly assist in understanding and managing climate change. Measurements over long periods provide a reliable long-term record of Earth’s climate and improve our understanding of the changing planet,” an ESA press release accompanying the study explains.

“Sea ice can be measured by different types of satellite data. Radars on satellites such as ESA’s Envisat can acquire high-resolution images through clouds and darkness. This is particularly useful when observing the inaccessible Arctic,” it concludes.