Yesterday Margo did a very thorough sea ice update.
If
you are short on time skip to approximately the 30 minute mark.
If
you are even more short on time you can read my partial synopsis
below.
Arctic
Sea Ice Update & Climate Cast with Margo - August 18, 2018Margo had the insight that you could use a layer giving the temperature of ice to see areas where temperatures are above freezing.
The
other interesting point was that you can use the tool to determine
those areas where there is no cloud cover as they are unable to
measure the ice temperature where there is cloud cover.
This is from an article Sea Ice Surface Temperature Product from MODIS, a technical paper explaining the use of the MODIS system.
Any
pixel that has a temperature of less than 271.5K is considered to be
ice and any pixel with a temperature of 271.5K is considered to be
open water.....
During
the “warm period” during the summer period melting snow or any meltponds will likely have temperatures of melting fresh water
(273.15K) because it meltwater on the surface of multiyear ice floes
is less saline than water on top of first-year ice since salts are
ejected when an ice floe survives long enough to become a multi-year
floe
To translate:
In
thick water, such as north of Canada the ice has more fresh water
The
thinner ice is more saline and melts at a lower temperature.
This is what can be seen in such an area near the Pole.
Margo
goes into this in greater detail in her video.
That dark area may be a meltpond or, with the ice being so thin, we may be seeing blue water through a thin layer of ice.
Margo then went into the huge increase of methane emissions around the world but particularly in the Arctic.
We
are also seeing this in the East Siberian Arctic Shelf (ESAS)
Surface
methane in the Arctic
At 850
hPa ( approx. 5,000 feet)
At 500hPa (approx 16,500 feet)
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