Predictions: Looking Back and Forward

Arctic Summer Sea Ice, last year:
Alas, while NSIDC did not post a convenient graph with the long term trend for the minimum, they did report that minimum sea ice was the 3rd lowest on record. September and August were just below the trend line (at 3rd lowest), whereas October sea ice was exactly in between the trend and 2007 as 2nd lowest. So sea ice extent was barely within my wide band, and definitely not between my tighter bounds. Grade: B-.

This year: I predict that it is more likely we are lower than the trend, but possibly higher than the trend. 2009 was pretty much right on the trend, so this means that I'm stating 60% less than 2009, 40% more than. The weird Arctic weather this winter meant a warmer Arctic, so possibly thinner ice... however, the current extent actually just passed 2009 (but it has been averaging lower over the first two months).

Global Mean Temperature in 2009, last year:
2nd warmest in GISS, 6th? warmest in HadCrut, but haven't done the calculation for RSS/UAH. Therefore, in range of my prediction, maybe a little higher even than my language suggested was most likely. Grade: A-

This year: Well, we've had 2 months of record or near record temperatures in the UAH dataset so far, and some pretty warm months from GISS and HadCrut, and the MEI index (http://www.esrl.noaa.gov/psd/people/klaus.wolter/MEI/table.html) has just shot up to its highest level since 1998 and temperatures historically lag the MEI... I'd go with a 50% chance of 2010 being the warmest year on record in at least one dataset... though the weak but slowly recovering sun and the new stratospheric water vapor study by Solomon may both point towards less likelihood of exceeding record warmth. If 2010 is not a record year, I doubt that 2011 will be (the el Nino pattern won't line up quite right), and I'd guess 2012-2013. I still stand by eating my hat if we haven't gotten a record by 2015.

Atlantic Hurricane Frequency, last year:
Made a 3 year prediction last year: I'm thinking that I'll be proved wrong as last year was low and I predict that this year will be low, but for now: Grade: Incomplete

This year: El Nino may depress hurricane formation in the early summer. Late summer/fall may see a hurricane resurgence, but I doubt that this year will exceed "average".

Long term sea level rise, last year and this year:
My guess last year seems fine, and I'll keep with it: continued 3 mm/year (range of 2 to 4).

Greenland and Antarctic Melt: (as measured by gravity satellites)
If by "slow down" I mean "possible downward revision of Antarctic melt due to new analysis" then I was right on the money. I'm not sure this is a good annual measure, as I don't know where to find annual data. I foresee continued melting, but in Antarctica melt is exceeding expectations (which were for, if anything, short term ice growth not melt), so I presume we'll see a "regression towards expectations" much like we've seen with Arctic sea ice melt (but at the same time, expectations will shift to more closely reflect current measurements).

-Marcus, 3/10/2010.