Chart of the Day: Annual Global Temperature Anomaly Relative to a Base Average

From a blogger that devotes their life to debunking climate denial comes this chart

If you’re younger than 30, you’ve never experienced a month in which the average surface temperature of the Earth was below average.


The variability we observe in surface temperature comes primarily from understood patterns of weather. Many have heard of El Niño, when the eastern Pacific Ocean is warmer than average. The eastern Pacific is so large that when it is warmer than average, the entire planet is likely to be warmer than average. As we look at averages, 30 years, 10 years, or even one year, these patterns, some years warmer, some cooler, become less prominent. The trend of warming is large enough to mask the variability. The fact that there have been 30 years with no month below the 20th century average is a definitive statement that climate has changed.


Chart showing warming temperatures relative to average over 20th century

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3 Responses to Chart of the Day: Annual Global Temperature Anomaly Relative to a Base Average

  1. Adam Miller
    Adam Miller March 3, 2015 at 10:40 pm #

    Um, what? Everything on this site is political. Climate change is probably among the least disputed, empirically.

    (Or maybe the username was intentional and I’m whiffing badly)

  2. Bill Lindeke
    Bill Lindeke March 4, 2015 at 9:00 am #

    funniest comment of 2015 so far

    • Matty Lang
      Matty Lang March 4, 2015 at 10:28 am #

      It almost got me, but the double entendre of the name is the key to success on this one.

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