I was discussing the recent global heat records set last week when I was struck by a remarkable comparison between two sets of numbers.
The first set is shown in this graph that includes the recent heat records, with last week rising by about 0.3C as it crested the old record of 16.92C and moved on to reach 17.23C:
The second set is given in this graph that depicts the changes in global tempetures over the past 12,000 years:
Now compare the scales.
That 0.3C in the first graph is comparable in magnitude to the change between years that are 3000 years apart in the latter graph.
That means the rise in temperatures during just last week is similar to the change in typical global temperatures over a span of 3000 years(!).
Granted, the normal annual variation is around 4C, but still...
Along those lines, the 4C annual variation is comparable in magnitude to the difference between glacial conditions (a mile of ice over Boston) 20,000 years ago and the climate in 1900.
I have no idea why I never noticed this comparison before, but color me gob-smacked.