During a presentation held today, April 24, at the Royal Society in London, experts from the European Space Agency (ESA) presented the first seasonal variation map of Arctic sea-ice thickness, as compiled by the CryoSat spacecraft.
The satellite was launched nearly one and a half years ago, and it produced its first map of Arctic sea-ice thickness back in 2011. However, at the time, it did not have sufficient data to compile a dataset showing seasonal variations.
The 2011 maps were the product of data the satellite acquired between January and February. The new maps feature data spanning the entire 2010-2011 winter season, experts from ESA announced today.
What separates CryoSat data from those produced by previous satellite measurements is the high-resolution the spacecraft's instruments are capable of. Its radar altimeter is capable of extreme precision, and is better equipped for this type of study than any other instrument before it.
The altimeter works by emitting very short radar pulses, and then measuring the time it takes for those signals to return to its detectors. As it flies over the planet, these times change depending on the landscape features below. All of these data are then processed and compiled into maps.
The accuracy of CryoSat measurements is constantly verified, primarily through investigations conducted on the ground, in areas covered by the satellite. ESA is collaborating with NASA for this complex endeavor.
“In the coming years, the Arctic will become a very important geo-political region,” says the director of the ESA Earth Observation Program, Volker Liebig.
Between “15 to 20 percent of the world’s oil and gas reserves are expected there, and we will find shorter shipping routes as the ice melts. Satellites will play and ever-important role in the sustainable management of this sensitive region,” he goes on to say.
In addition, the influence of the Arctic on global warming and climate change, and vice versa, is extremely complex. Over the coming years, the satellite will focus on these interplays increasingly often, using extremely precise instruments.