Arctic Sea Ice Season Melt 2015 - A Satellite View on Sea Ice
After the Arctic sea ice has hit in 2014/2015 a record minimum for its winter seasonal extent, the 2015 melt season leading up to the September minimum was eagerly awaited. Compared to the record September minimum of 2012, the sea ice extent registered an increase both in September 2014 and 2013.
The animation shows this year’s melt season development based on daily satellite data. One important aspect that needs to be emphasized for the 2015 sea ice melt season, is the opening of both the North-East and North-West passage. Also, an interesting phenomenon can be viewed in the Beaufort Sea: a so-called “arm” gets detached from the the central ice pack and melts consequently faster in the relatively warm sea water. Overall, the sea ice extent in September will present a distinct decline in comparison to the previous two years. This reinforces the long term downward trend of the Arctic sea ice extent, caused by the human-induced global warming.
The data was provided by the Japanese weather and climate satellite GCOM-W1, which is carrying the microwave sensor AMSR2 (Advanced Microwave Scanning Radiometer-2). GCOM stands for Global Change Observation Mission and refers to a series of satellites conducting observations of both global water circulation (W-Series: water and ice) and climate (C-series). The GCOM-W1 satellite is the first of its series and started providing data in the summer of 2012. The AMSR2 sensor provides highly accurate thermal microwave radiation measurements.
A novel method developed at the University of Hamburg calculates from daily data the ice cover in a contiguous manner and with a 3km spatial resolution (Beitsch et al. 2014). Thus, many detailed features that remained previously undetected by other methods - for example fractures in the ice cover - can now be made visible.
Beitsch, A.; Kaleschke, L.; Kern, S. Investigating High-Resolution AMSR2 Sea Ice Concentrations during the February 2013 Fracture Event in the Beaufort Sea. Remote Sens. 2014, 6, 3841-3856. doi:10.3390/rs6053841