A “warming plateau”?

There’s was an article in The New York Times yesterday titled “What to make of a warming plateau”. In addition to there being no Comments available there, I find the article annoying, since I see no evidence that there is such a plateau, working from original data. See below.

AnnualAnomaliesBarChartWithQuantilesOfVariability

This uses surface temperature anomaly data from NOAA, and calculates two moving window quantile regressions with a cosine taper on the windows, one using a 9 year window width, the other using a 13 year window width. The bright green line shows the median (or 0.5) quantile of the 9 year regression, with the red and magenta showing the 0.3 and 0.7 quantiles, respectively. The dark green line shows the median quantile for the 13 year regression, with dashed dark red and dashed dark orange showing its 0.3 and 0.7 quantiles.

There’s evidence for increased variability here, but there is nothing to justify a conclusion of some kind of plateau.

(Added on 22nd June 2013: A good post from Dr Greg Laden on the same subject.)

(Added 26th June 2013: The quantile regression used here has recently been used to identify rapid Antarctic warming in the coldest regions by Dr Christian Franzke in an April 2013 publication.)

(Added 27th August 2013: Ari Jokimäki’s AGW Observer concurs, providing much more detail.)

TemperatureAnomalyQuantiles_2013-05-31_224635

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About hypergeometric

See http://www.linkedin.com/in/deepdevelopment/ and http://hypergeometric.wordpress.com
This entry was posted in climate, environment, geophysics, maths, oceanography, physics, science, statistics. Bookmark the permalink.

One Response to A “warming plateau”?

  1. Pingback: “Overestimated global warming over the past 20 years” (Fyfe, Gillett, Zwiers, 2013) | Hypergeometric

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