Greenland Temperatures In 2017

By Paul Homewood

As we all know, Greenland is warming up rapidly, causing the ice sheet to melt faster and faster.

Well, according to the BBC and New York Times, at least.

Only one slight problem – the temperature record shows quite a different story.

Each year, the DMI publishes the Greenland – DMI Historical Climate Data Collection:

http://www.dmi.dk/fileadmin/user_upload/Rapporter/TR/2018/DMIRep18-04.pdf

Greenland has a number of very long running weather stations covering most of the country’s coastal regions, except for the far north. The report provides temperature graphs for each:

On both east and west coasts, it is abundantly clear that temperatures were just as high in the 1930s and 40s as they have been in the last decade or so, with the exception of the anomalously mild year in 2010.

And the reason is simple – the AMO:

There is certainly no evidence of rising temperature trends, and every likelihood that temperatures will plummet again when the AMO turns cold again.

Meanwhile for the second year running, the Greenland ice sheet has been increasing at close to record levels:

http://www.dmi.dk/en/groenland/maalinger/greenland-ice-sheet-surface-mass-budget/

Not that you will any of this on the BBC!

NB, DMI have this handy explanation of how the ice sheet gains and loses mass:

Ice flow

Due to gravity, ice flows slowly outwards like dough on a kitchen counter. When snow falls on top of the ice sheet year after year, the layers below are slowly compressed into ice. In the central part of the ice sheet, where little if any melt occurs, new layers will therefore continually be added. The ice does not grow in height, however, since the extra ice is balanced by the flow away from the center. Further out towards the coast we find the equilibrium line, where snowfall and melt are exactly balanced. Below the equilibrium line, there is more melt than snowfall and here the net mass loss is countered by the flow coming out from the center of the ice sheet. Here it is the ice sheet itself which melts.

For an ice sheet that neither grows or shrinks, there is at all points averaged over the year a balance between

the amount of snow that falls and is compressed to ice
the amount of snow and ice that melts or evaporates (sublimates) and
the amount of ice that flows away due to the ice motion

The two first contributions make up the surface mass balance. For the ice sheet as a whole, there is a balance between the surface mass balance and the amount of ice that calves into the ocean as icebergs.

If climate changes, the surface mass balance may change such that it no longer matches the calving and the ice sheet can start to gain or lose mass. This is important to keep track of, since such a mass loss will lead to global sea level rise. As mentioned, satellites measuring the ice sheet mass have observed a loss of around 200 Gt/year over the last decade.