Doubting global warming?

My colleague John Young, who is a member of the Univ. of Wisconsin Chaos and Complexity Seminar group I join when I am in Madison, circulated this video to the group. One wishes the current contenders for the Republican presidential candidate nomination, who are either in denial or indifferent to the climate change issue, would have a look. They would probably want to de-fund the climate.gov team that put the video together.
 

Decades ago, the majority of the Arctic's winter ice pack was made up of thick, perennial ice. Today, very old ice is extremely rare. This animation tracks the relative amount of ice of different ages from 1987 through early November 2014. Video produced by the Climate.gov team, based on data provided by Mark Tschudi.

From the more extended description:

This animation tracks the relative amount of ice of different ages from 1987 through early November 2014. The first age class on the scale (1, darkest blue) means "first-year ice,” which formed in the most recent winter. (In other words, it’s in its first year of growth.) The oldest ice (>9, white) is ice that is more than nine years old. Dark gray areas indicate open water or coastal regions where the spatial resolution of the data is coarser than the land map.

As the animation shows, Arctic sea ice doesn't hold still; it moves continually. East of Greenland, the Fram Strait is an exit ramp for ice out of the Arctic Ocean. Ice loss through the Fram Strait used to be offset by ice growth in the Beaufort Gyre, northeast of Alaska. There, perennial ice could persist for years, drifting around and around the basin’s large, looping current.

Around the start of the 21st century, however, the Beaufort Gyre became less friendly to perennial ice. Warmer waters made it less likely that ice would survive its passage through the southernmost part of the gyre. Starting around 2008, the very oldest ice shrank to a narrow band along the Canadian Arctic Archipelago.