Wednesday, April 15, 2015

March GISS up 0.06°C

As several commenters have noted, GISS is up by 0.06°C, from 0.78 to 0.84. I had expected a small rise; David Appell was close. That's one of the hottest months on record, and makes 2015 a very warm year so far. TempLS rose by a smaller amount, and the troposphere indices declined.


Here is the GISS map. As with TempLS, N America is bipolar (more warm than cold), Russia and N Europe hot, and a hotspot near Sudan.



And here is the corresponding TempLS map, as on Tax Day (for some):


14 comments:

  1. By my count: It is the 3rd warmest March on record, the 5th largest anomaly for any month, and Jan-Mar 2015 is now the warmest Jan-Mar period on record. Given that it looks reasonably likely we are still in the (long drawn-out) process of entering an El Niño, I’d give good odds on 2015 being warmer than 2014 (and therefore yet another warmest year on record).

    -MMM

    ReplyDelete
  2. With the prospects of a strong el Nino developing next autumn/winter, it's not unlikely that 2015/2016 becomes like 1997/1998 when global temperatures leaped to a higher level.

    Nick, Giss has picked up a little hotspot at the Antarctic Peninsula, which the TempLS map hasn't. Do you think GISS use other data ( SCAR), or is the difference due to adjustment, land/sea averaging etc?

    ReplyDelete
    Replies
    1. Olof,
      Sorry I miised that q. I think the spherical harmonics of TempLS smoothes it out (because the ocean is cool), while GISS shows it because it is a relatively large number of land stations, enough to change a few cells to high.

      Delete
  3. Good year to bet on there being a new record minimum Arctic Sea ice.

    ReplyDelete
  4. Well it's been running at -2 sigma all winter and spring.

    http://nsidc.org/data/seaice_index/images/daily_images/N_stddev_timeseries.png

    Plus we are nearly certain to have an El Niño this year… may even be a repeat of 1997/1998 as Olof said.

    Depending on how things go, minimum ice could be off the charts bad this year.

    ReplyDelete
  5. Extent has been low but volume hasn't. Arctic temperatures (from the observations available) have generally cooled since 2012, indicating a variability shift which has coincided with increased warming elsewhere on the planet.

    I think there's a good chance we'll be waiting several years for the next record minimum.

    ReplyDelete
  6. I think the various Arctic sea ice prognostication contests have shown how difficult it is to predict minimum extent (or even, September average extent). There is low correlation between detrended winter extent and detrended summer minimum, and as far as ENSO is considered, looking at MEI it looks like 2007 was a weak El Nino transitioning into La Nina, whereas 2012 was a La Nina transitioning into weakly positive MEI, so there's no pattern there, either.

    Having said that: I wouldn't be surprised if this year was a new minimum (we do have a long-term trend, so I expect minimums every few years), I just wouldn't bet on it.

    -MMM

    ReplyDelete
    Replies
    1. PaulS—(at least reconstructed) temperatures in the Arctic have been warm all winter.

      http://ocean.dmi.dk/arctic/plots/meanTarchive/meanT_2015.png

      My guess (and it's a guess) is that we didn't get the "usual" recovery this winter, so I expect to see the surface ice (even more) vulnerable to meteorological disruptions. If we get some strong late summer storms, I expect to see the ice get shredded: I think the decrease in mechanical stability is a bigger driver of ice loss on “bad years” than the warming temperatures by themselves.

      MMM---to be clear I was thinking of betting quatloos on Lucia's blog. Last year's minimum with JAXA was 4.899, my bet was 4.94, which wasn't too bad.

      But if I’m right about the ice being less stable, it’s even less predictable this year than in past ones. Also, years with significant ice loss seem anti-correlate with positive ENSO phase, so there is that. to factor in too..

      Delete
    2. I would expect PIOMAS to show a slight increase in sea ice volume at maximum over 2013 and 2014. The volume maximum occurred sometime in mid-April, we'll just have to wait for the monthly PIOMAS data release to see what it was.

      Both PIOMAS and the Drift Age Model show the Beaufort Gyre moving thicker ice into the Beaufort and Chukchi Seas. This has in the past been a significant defense against these areas melting out in summer.

      Unless we get a 2007-like perfect storm of weather conditions I would be surprised to see a new minimum set for extent or area this year. That said, I would not be surprised to see the North Pole surrounded by significant expanses of open water this fall.

      I'd also recommend for those who are interested in arctic sea ice visiting Chris Reynold's Dosbat blog

      Delete
    3. Yes, Neven's Sea Ice Blog is IMHO *the* goto site for all things arctic sea-ice related. Chris and I have been regulars there ever since it started. Chris began Dosbat to elucidate more fully ideas that came up from discussions at Neven's.

      Delete
  7. Well, April remains cool, but it does look like the forecast for the last days of the month is looking a bit warmer.

    ReplyDelete
    Replies
    1. Yes, I think April will look like last November.

      I should mention that I'm recovering from a disk crash here. Files are backed up, but some repair is needed on the automatic update arrangements. Could be patchy for a day or two.

      Delete