In the Arctic, the sea ice volume 4-yr average reached a new record low last week due to climate change. The new milestone was 13.6 thousand km³.

Q: Where’s the data source for this plot?
A: Here: arctic-sea-ice-volume-for-july-2019-from-piomas/
Q: How can anyone make a 4–year average graph?
A: Easy. Use a computer. Add all the ice for the latest 4×365 days, divide by that number of days.
Q: Why would I even do that?
A: Let’s say you want to know how much ice we have in the latest 4–year period compared to the 4–year periods before that.

Due in large part to ongoing Collapse of Arctic Sea Ice our Frozen Earth is Going South.