skierinvermont Posted September 24, 2013 Share Posted September 24, 2013 It's not as simple as solar radiation albedo. You realize that snowcover extent effects air temperatures at night too, right? Snow cover extends much further south in the winter, and the greater the snow cover, the easier it is to generate very cold air masses further south. Yes obviously snowcover anomalies in winter effect OUR weather more (ie 'cold air masses further south). But snowcover anomalies in June effect Siberian air temperatures tremendously. The fact that there is more snow coverage in winter is irrelevant so stop bringing this point up. The anomalies in summer are just as large as the anomalies in winter in areal coverage. 5 million sq km is 5 million sq km in both summer and winter. And in terms of global temperatures, it is as simple as albedo. The insolation change in summer is far greater than in winter. In terms of effecting the local temperature, snowcover in winter might be as important as summer because a lack of snow in winter allows energy to be stored during the day and released at night, holding up nighttime temperatures. But day time temperatures would not be effected as much because the insolation change is much less. Link to comment Share on other sites More sharing options...
tacoman25 Posted September 24, 2013 Share Posted September 24, 2013 Perhaps this was already answered, but do snow cover anomalies in summer include snow-covered ice? Link to comment Share on other sites More sharing options...
skierinvermont Posted September 24, 2013 Share Posted September 24, 2013 Perhaps this was already answered, but do snow cover anomalies in summer include snow-covered ice? The Rutgers data and charts are land-only. FSU has a version that includes ice and a version which does not. The version people have been using includes ice. I believe this includes all ice, not just snow covered ice. It would be difficult to distinguish the two (or even precisely define "snow-covered" vs a mixture of old snow and ice) and they are functionally pretty similar in terms of albedo. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted September 24, 2013 Author Share Posted September 24, 2013 Winter snow cover gains haven't come close to the snow cover loss in April-June. And they never will. The Spring has a lot more it will lose as the heat in forcing and the oceans and from the South keeps getting stronger in Spring. Unless we are just going to go by the Cherry-picked 1995-2009 FSU baseline. But of course it keeps getting posted. Link to comment Share on other sites More sharing options...
tacoman25 Posted September 24, 2013 Share Posted September 24, 2013 Winter snow cover gains haven't come close to the snow cover loss in April-June. And they never will. The Spring has a lot more it will lose as the heat in forcing and the oceans and from the South keeps getting stronger in Spring. Unless we are just going to go by the Cherry-picked 1995-2009 FSU baseline. But of course it keeps getting posted. Actually, according to skiier even on a 1971-2000 baseline the positive anomalies last winter were about equal to the negative anomalies this summer. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted September 24, 2013 Author Share Posted September 24, 2013 That is one year. ONE YEAR. Secondly Skier should know May is far more important than July. I doubt if we drop August which is irrelevant for May it's no longer the same. Snow cover anomalies would be more important in late winter as well. Feb-April vs Dec-Jan. Most important from March-June overall. Link to comment Share on other sites More sharing options...
Jonger Posted September 24, 2013 Share Posted September 24, 2013 Spring snow looks really bad until you drop it into a context. It will take another 140 years at the current pace to cut the spring snow in half. Link to comment Share on other sites More sharing options...
tacoman25 Posted September 24, 2013 Share Posted September 24, 2013 Good graphs, Friv. Looks like the trend for spring snow cover anomalies is fairly flat since the early 1990s (especially since that graph doesn't include 2013, which was well above normal in March/April). Whereas late spring/early summer have continued to trend sharply downward. However, I would think that by July/August, a lot of that snow from May would have melted most years anyway. But I understand how the earlier melt would lead to stronger albedo earlier. The correlation between May/June snow cover and Arctic sea ice was thrashed a bit this year. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted September 24, 2013 Author Share Posted September 24, 2013 Spring snow looks really bad until you drop it into a context. It will take another 140 years at the current pace to cut the spring snow in half. that is not context. You trashed people who did the same with the piomas data. Link to comment Share on other sites More sharing options...
Jonger Posted September 24, 2013 Share Posted September 24, 2013 that is not context. You trashed people who did the same with the piomas data. Um, whats wrong with it.... I put the chart roughly into a 1-34M Sq KM chart and fit it into the range. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted September 24, 2013 Author Share Posted September 24, 2013 Um, whats wrong with it.... I put the chart roughly into a 1-34M Sq KM chart and fit it into the range. Nobody expects that much Spring snow cover to vanish by 2150 or anytime soon. It's not the issue at hand. Link to comment Share on other sites More sharing options...
Jonger Posted September 24, 2013 Share Posted September 24, 2013 Friv, every trend for any graph will always look bad when the peak and the valley are the range of the entire plot you are trying to chart. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted September 24, 2013 Author Share Posted September 24, 2013 Good graphs, Friv. Looks like the trend for spring snow cover anomalies is fairly flat since the early 1990s (especially since that graph doesn't include 2013, which was well above normal in March/April). Whereas late spring/early summer have continued to trend sharply downward. However, I would think that by July/August, a lot of that snow from May would have melted most years anyway. But I understand how the earlier melt would lead to stronger albedo earlier. The correlation between May/June snow cover and Arctic sea ice was thrashed a bit this year. Exactly. Timing is everything. The correlation to Sea Ice wouldn't be hindered to much. The connection to it being the leading driver of the persistent -NAO would be really hurt. Both the snow cover and sea ice had extremely similar paths. Which is nothing but a comparative correlation. I am not trying to compare them as if there is cause and effect. In the longer term there is abnormally strong correlations with snow cover and sea ice loss though. April = June May = July June = August. Link to comment Share on other sites More sharing options...
Geos Posted September 26, 2013 Share Posted September 26, 2013 NH snow cover area made a huge jump! Link to comment Share on other sites More sharing options...
tacoman25 Posted September 26, 2013 Share Posted September 26, 2013 Wow. And it's not done yet. Does anyone have the stats for all previous Octobers and NH snow cover? Link to comment Share on other sites More sharing options...
ORH_wxman Posted September 26, 2013 Share Posted September 26, 2013 Wow. And it's not done yet. Does anyone have the stats for all previous Octobers and NH snow cover? Link to comment Share on other sites More sharing options...
tacoman25 Posted September 26, 2013 Share Posted September 26, 2013 Thanks, Will. So I ran the composite for winter temperatures following the 9 highest October years (the ones with over +2 million anomalies). Sure seems to signal a better chance for winter cold in the NH mid-latitudes, as I asserted earlier in this thread. Link to comment Share on other sites More sharing options...
tacoman25 Posted September 27, 2013 Share Posted September 27, 2013 Quite a bit of snow cover gain in Russia/Siberia over the past week, as expected. Link to comment Share on other sites More sharing options...
Geos Posted October 5, 2013 Share Posted October 5, 2013 After a brief pause in the snow cover expansion, it is shooting upwards again. Above normal. Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted October 5, 2013 Author Share Posted October 5, 2013 the Russian side is amazing . Link to comment Share on other sites More sharing options...
bluewave Posted October 5, 2013 Share Posted October 5, 2013 Nice jump in the snow cover with the AO drop during the second half of September. We saw a very fast increase near the end of last October during the big late month AO plunge. AO index during Last October late month increase 2012 10 20 -0.8612012 10 21 -1.8172012 10 22 -2.5382012 10 23 -2.9782012 10 24 -3.1952012 10 25 -2.9122012 10 26 -2.3932012 10 27 -2.0582012 10 28 -1.7902012 10 29 -1.7182012 10 30 -2.0752012 10 31 -2.460 Link to comment Share on other sites More sharing options...
The_Global_Warmer Posted October 6, 2013 Author Share Posted October 6, 2013 Beautiful. Link to comment Share on other sites More sharing options...
bluewave Posted October 6, 2013 Share Posted October 6, 2013 6th snowiest September on record and the first with above normal snow cover since 2002. 9 6,492 5,235 1,257 6/45 7,762 (1972) 3,838 (1990) Link to comment Share on other sites More sharing options...
Geos Posted October 9, 2013 Share Posted October 9, 2013 Siberia will totally snow covered by the weekend at this rate! Link to comment Share on other sites More sharing options...
bluewave Posted October 9, 2013 Share Posted October 9, 2013 This is the best Eurasian snow cover for 10/8 since 2002. 2013 2002 Link to comment Share on other sites More sharing options...
SnoSki14 Posted October 10, 2013 Share Posted October 10, 2013 Canada needs some help though. Link to comment Share on other sites More sharing options...
Midlo Snow Maker Posted October 10, 2013 Share Posted October 10, 2013 September was ranked 6 out of 45 for the most cover for the NH per Rutgers Week 39 ranked 7th most. Values below are in million sq. km 1977 15.09 1972 14.02 2000 12.76 1973 11.50 2002 10.84 1989 10.82 2013 10.36 1983 10.23 Link to comment Share on other sites More sharing options...
ORH_wxman Posted October 10, 2013 Share Posted October 10, 2013 September was ranked 6 out of 45 for the most cover for the NH per Rutgers Week 39 ranked 7th most. Values below are in million sq. km 1977 15.09 1972 14.02 2000 12.76 1973 11.50 2002 10.84 1989 10.82 2013 10.36 1983 10.23 All of those years had some pretty memorable arctic outbreaks early in the winter...most of them in December, although 2002 was more in Jan 2003. We'll have to see if this year follows suit. Link to comment Share on other sites More sharing options...
Jonger Posted October 10, 2013 Share Posted October 10, 2013 September was ranked 6 out of 45 for the most cover for the NH per Rutgers Week 39 ranked 7th most. Values below are in million sq. km 1977 15.09 1972 14.02 2000 12.76 1973 11.50 2002 10.84 1989 10.82 2013 10.36 1983 10.23 All of those years had some pretty memorable arctic outbreaks early in the winter...most of them in December, although 2002 was more in Jan 2003. We'll have to see if this year follows suit. Dec 2002 featured an early winter start in the Midwest, but we had a thaw at the end of the month. We hit -16℉ at the beginning of Dec, I believe it was a record. Link to comment Share on other sites More sharing options...
nzucker Posted October 10, 2013 Share Posted October 10, 2013 Something tells me that this winter is going to be MUCH colder than recent years. Link to comment Share on other sites More sharing options...
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