Quick Set of Predictions

Arctic Summer Sea Ice:

I predict that the minimum Arctic Sea Ice extent in 2009 will be somewhere between a continuation of the long-term trend and somewhat worse than 2007.  I think the likeliest possibility is somewhere between the 2008 and 2009 levels.  

Reasoning:  I think 2007 and 2008 may indicate a real departure from the long-term trend, but I don't think that is in any way confirmed yet.  Current sea ice levels are about where 2007 was before the 2007 record low sea ice extent, and the ice is "younger" than it was then.  However, 2007 required some "favorable" atmospheric conditions for pushing ice out of the Arctic which may not reappear this year.  

I predict that the 2007 record will almost certainly be broken by 2012.

Total disappearance of summer sea ice:  My WAG is that we'll see this in the 2nd half of the century.  Some scientists have indicated that it may happen as early as 5 years from now (based on new models post-2007):  this seems unlikely to me, but, *shrug*, there are positive feedbacks at work here, and a "perfect storm" of currents, warm year, and weak ice could lead to surprises...

http://www.nsidc.org/acticseaicenews

Global Mean Temperature in 2009:

Almost certainly higher than 2008.  2008 started as a strong la nina year, and the coldest year in 8 years.  Absent a volcano, a 2nd strong la nina, or a meteor collision, all of which are unlikely, I don't think that the "PDO shift" or the "weak sunspots" will be enough to keep temperatures below 2008 levels.  (Any data set, GISS, HADCRUT, UAH, or RSS)

However, the sunspot and PDO issues will, I think, keep it from being a record warm year, absent a strong el nino.  (though higher likelihood of this than a lower than 2008 year)

Next Global Mean Temperature Record:

I would guess sometime in 2011-2012.  2009 or 2010 is possible, with a strong el nino.  If we don't see a new record in at least one dataset by 2015, I'll eat my hat.  

Atlantic Hurricane Frequency:

I'm going to go with Kerry Emmanuel, and predict more Cat 3 and above Atlantic hurricanes than the long term average over the next 3 years.  This is a lower confidence prediction:  too much goes into hurricane formation other than just surface temperature of the oceans.  I doubt we'll see 2005 exceeded for a while.

Long term sea level rise:  (as measured by satellites)

I'll guess continued 3 mm/year (range of 2 to 4).  

Greenland and Antarctic Melt:  (as measured by gravity satellites)

I'll guess that they will slow down temporarily.