Arctic sea ice decline happened faster than expected. This has the effect of accelerating global warming because less of the Sun’s energy is reflected back into space by ice.
Northern Hemisphere snow also sends some of that energy back into space. The amount of snow cover we have is also declining.
The warming of the Arctic region is also probably causing an increase in the amount of CO2 and Methane, previously frozen in permafrost or offshore, that is going into the atmosphere. For this and other reasons, Methane, along with other greenhouse gases, are increasing. I quickly add that stories you’ve heard of a civilization “methane bomb” in the Arctic are not supported by the best available science. But these additional greenhouse gases still count.
Now we are learning that glacial ice, in particular in Antarctica, is melting faster than expected.
That video is from a recent post by Peter Sinclair, who has more on glacial melting.
We knew a lot of the additional heat (from global warming) was going into the oceans, but now we have learned that a LOT of this heat is going into the ocean. This heat goes in and out, so what has been going in will likely be going out (into the atmosphere).
This causes me to look at a graph like this …
… and figure that warming over coming decades will be at, near, or even above, the range previously estimated.