First Ice free day poll

[DavidR]

 
These temperatures will produce significantly more melt than we are currently experiencing every year and less winter volume. 

Are you sure it isn't mainly less winter volume causing higher winter temperatures? Perhaps also extra heat built up in melt season gets vented to atmosphere causing higher temperatures? It isn't unreasonable to believe higher temperatures cause less winter volume even if there is also cause and effect the other way so I don't have much objection to that part.


Regarding higher temperatures causing more melt, are you aware temperatures in summer seem lower not higher:
eg hottest year 2010:

http://www.esrl.noaa.gov/psd/cgi-bin/data/timeseries/timeseries1.pl
http://data.giss.nasa.gov/gistemp/tabledata_v3/ZonAnn.Ts.txt

Both air and sea temperatures appear to be rising much faster in winter than summer. Half of the hottest 15 June temperatures in both  measures occurred before 1961 but there were hardly  any  'top 15'  months before 1961 in the months from Sept-Apr. Logically this would imply less ice formation in winter. 

While 2010 was the hottest year, 2012 was the hottest summer.

It is also clear that a hotter summer eg 2007, 2012 leads to significantly more melt.  As I pointed out in another post it generally takes three unusually warm years to  get a new record low. However with the annual average rising so fast, the current record warm trio 2010-1012 will be just average by 2021. I don't see how the pack will not melt  out once that  becomes the norm.

[LRC1962]

Both air and sea temperatures appear to be rising much faster in winter than summer. Half of the hottest 15 June temperatures in both  measures occurred before 1961 but there were hardly  any  'top 15'  months before 1961 in the months from Sept-Apr. Logically this would imply less ice formation in winter. 

Could that be a result of the reflection of solid ice? >Would it not be more difficult to get a good air temp if not only do you have the sun coming from above but also being reflected off the ice at the same time? Not only that but with open water you would have grater evaporation that would keep air closer to sea temps? Mind you the high humidity would also encourage higher melt?
As for winter the slower jet stream is pulling far more heat into the Arctic then before.

[DavidR]

Both air and sea temperatures appear to be rising much faster in winter than summer. Half of the hottest 15 June temperatures in both  measures occurred before 1961 but there were hardly  any  'top 15'  months before 1961 in the months from Sept-Apr. Logically this would imply less ice formation in winter. 

Could that be a result of the reflection of solid ice? >Would it not be more difficult to get a good air temp if not only do you have the sun coming from above but also being reflected off the ice at the same time? Not only that but with open water you would have grater evaporation that would keep air closer to sea temps? Mind you the high humidity would also encourage higher melt?
As for winter the slower jet stream is pulling far more heat into the Arctic then before.

I'm looking at the changes in temperature as a cause of increased melt, not as an effect of something else. That's a conversation for another thread.