Tuesday, February 26, 2013

January 2013 GISS up 0.17°C

I posted earlier about problems with GISS. They have now posted the January anomaly, and it is 0.61°C, up from 0.44°C in December. That's a big rise, but less than the big drop in December. TempLS recorded a similar rise (0.15°C), and I blogged about that and the reasons here. NOAA also rose from 0.42°C to 0.54°C.

As usual below the fold I'll show the comaparative spatial distributions.

Here is the GISS map for January:

And here is the TempLS map (from here), which uses spherical harmonics:

Previous Months

December 2011
August 2011

More data and plots


  1. I was wondering if the Dec blip was unusual, so I ran a difference between the GISTEMP temp and 3 month moving average. It's not unusual - there are bigger ones far back, and recent ones in Jan 2003, Dec 2002 and Dec 2004. They do seem to mainly occur in winter.

    High outliers can be a bit bigger, and are also mostly in winter. I guess that shouldn't be a surprise, we know the weather is less predictable in winter.

    Kevin C

  2. Kevin,
    I think this was mainly due to extra cold in cold places - Siberia and Alaska. So that fits with the theory.

  3. This comment has been removed by the author.

  4. Screwed up the link. Corrected version:

    I believe this is associated with a sudden warming stratospheric event (which occur in the Arctic). Report here from NASA.

    You also get occasional spikes in the monthly record associated with the Madden-Julian Oscillation.

    (You can see all of these more clearly in the daily version of UAH, which is oversampled for global weather at least, but better than monthly indexes for studying high-frequency phenomena).

  5. A bit more detail here. link.

    Here's a non-paywalled reference. link.

    In the weather-isn't-always-not-climate department, these sudden warming events are thought to be associated with vertical gravity waves generated over the Greenland Gyre (atmospheric internal gravity waves move predominantly vertically) that then break in the lower atmosphere.

    If the contrast between the lower troposphere and the stratosphere increases as it warms (this contrast does increase due to stratospheric cooling), you should see progressively stronger SWAs over time.

    There is also interest in whether there is a change in the Greenland Gyre over time too. Relevant IPCC link.

    1. Thanks, Carrick,
      I'll look into that more. Certainly the big winter (NH, it's damn hot here) oscillations seem to have a similar pattern, with big cold or warmth over NW America and Siberia. WUWT had an article by Willis about how cold it was in Jan 2012 in Alaska. Likewise Dec, but Jan 2013 was quite warm there.

    2. Nick, if you looked at AQUA AMSU data you might be able to generate similar patterns that you've gotten using the SST data.

      This is something I'd like to play with, just too much on my plate right now.

    3. I noticed I blew the explanation slightly. Should have read "that then break in the STRATOSPHERE".