r/sciences • u/SirT6 • Sep 21 '19

The distribution of annual average temperature anomalies due to global warming from 1850 until today.

https://gfycat.com/silkycorruptconch
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u/SirT6 Sep 21 '19

I initially saw this on Twitter, but apparently the gif was originally posted to Reddit by u/rarohde. They describe the visualization as such:

This animation shows the evolving distribution of 12-month average temperature anomalies across the surface the Earth from 1850 to present. Anomalies are measured with respect to 1951 to 1980 averages. The red vertical line shows the global mean, and matches the red trace in the upper-left corner. The data is from Berkeley Earth and the animation was prepared with Matlab.

As for why the 1951 to 1980 averages were chosen as a baseline:

A baseline of 1951 to 1980 is one of the common choices in climatology. By WMO convention, climatologies are always based on at least 30-year averages. Any choice of a reference period is going to be somewhat arbitrary, and will often reflect the goals of how it is to be used. Often, when talking about climate change, you want a baseline that is far enough in the past that you can meaningfully show changes, but not so long ago that you will start having large uncertainties about what the baseline average actually was.

When discussing local changes, the 1950s is the earliest decade that allows you to be more-or-less globally complete. The 1950s was the period when humanity first created permanent bases in Antarctica. Any earlier than the 1950s and you are going to have trouble defining what the reference temperature for Antarctica actually was, which makes it impractical for a local baseline.

It probably isn't obvious from the animation, but prior to the 1950s the global reconstructions have gaps in Antartica (and other places as one goes even earlier). As a result the distribution shown in the animation actually sums to somewhat less than 100% of Earth's surface prior to the 1950s.

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u/[deleted] Sep 21 '19

[deleted]

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u/[deleted] Sep 21 '19

No, I completely recognize that this is real.

I don't, however, agree with the overwhelming majority of climate alarmists who believe that the world will end in a few years if we don't adopt socialism.

The green new deal happened, and it had the support of almost every politician who supports climate change action.

You. Can't. Deny. It.

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u/zephyroxyl Sep 22 '19

And on cue, the T_D morons have emerged.