Additional information about observations of Arctic sea ice

In the last post, I forgot to put information about the sources of observations.

With year 1979 as the turning point, the observation periods can be split into two periods: pre-satellite and satellite. 

• Pre-satellite period

The pre-satellite data were based on terrestrial proxies regional offshore and aerial observations, etc. (IPCC, 2013). These data were the direct in-situ measurements collected on short time scales, difficult to measure accurately due to changes in edge and enormous size.

• Satellite period

Since 1979, satellite data have been available via microwave scanning, i.e. passive microwave remote sensing. This allows frequent collection of data on long time series available to global scale. Two major databases are operated by National Aeronautics and Space Administration (NASA) and the National Snow and Ice Data Center (NSIDC). 

 Instruments are :

• The Scanning Multichannel Microwave Radiometer (SMMR)
•  The Special Sensor Microwave/Imager (SSM/I)
• The Advanced Microwave Scanning Radiometer - Earth Observing System (AMSR-E)
• The Advanced Microwave Scanning Radiometer 2 (AMSR2)