implies a warming sea ice surface automatically gives warmer surface air.
~ The very reason for winter Arctic surface based inversions can only last till
sun rays become vertical enough to cancel them at the source, the "skin" surface.
1987's spring was very cold, it was well pre 1998 onwards steeper summer demise of Arctic sea ice volume and extent.
We notice NOAA ESRL "surface skin" temperatures with same color scales Mean Composite March 1 to 15 1987 followed by 2017. The first deep signal gathered here is how massively colder Arctic Ocean ice pack was in 1987, nearly all of the Arctic Ocean in deep purple, with 238 Kelvin at the Pole, 246 degrees Kelvin at its periphery. Note the red zone North of Atlantic ocean, warmer than 264 kelvin, this is the only common mean temperature with these 2 periods 30 years apart. 2017 has geographically much warmer skin temperatures, reflecting the thinner sea ice locations.
Since the prime refraction rule posits surface air temperature always warmer than "skin temperature"
the surface air from 1987 to 2017 warmed proportionally while always warmer than sea ice , again only the extreme North Atlantic has had similar temperatures between 1987 and 2017. Since 1987 same period interval, the North Pole area warmed 14 to 20 C exactly where the thinner ice is today.
The key source of this rule is at top of ice or snow skin, its temperature follows the surface air temperature trends. Top of thinner sea ice is much warmer than thick sea ice. Therefore the air has warmed along with the advent of thinner sea ice by substantial average margins. This absolutely implies a current much thinner near North Pole sea ice pack, while very thick multiyear ice North of Ellesmere and adjoining Islands are now the last remnants of a once much thicker Polar ocean pack spread out all the way to Russia.
Like a mirror, top of sea ice temperatures varies with surface air in tandem, if ice becomes warmer so does the air, the top skin is always cooler for rather simple and complex reasons, to be explained on another essay. Only solar forcing, an external input of energy, with especially higher elevation sun rays, warm the top of ice/snow to render sea ice to air interface isothermal. However, now you can study indirectly where the thinner ice is with mere temperature maps because of the relation between top of ice and surface air deduced from the prime refraction rule. WD March 26,2017