Jump to content
  • Member Statistics

    17,609
    Total Members
    7,904
    Most Online
    NH8550
    Newest Member
    NH8550
    Joined

And we begin... Part Deux


Recommended Posts

  • Replies 436
  • Created
  • Last Reply

Can you check '08's snow/ice pixel count?

Thx in advance.

I know '08 finished quite poor in the monthly anomaly. Not sure what it was on this exact date. It was the last October we had that finished below average for NH snow cover. '09 and '10 of course were above average.

Link to comment
Share on other sites

I know '08 finished quite poor in the monthly anomaly. Not sure what it was on this exact date. It was the last October we had that finished below average for NH snow cover. '09 and '10 of course were above average.

Yeah...I knew the month itself was below but wasn't sure where we stood now compared to '08...it seems like that year isn't a terrible analog to work with from a recent standpoint.

Link to comment
Share on other sites

Yeah...I knew the month itself was below but wasn't sure where we stood now compared to '08...it seems like that year isn't a terrible analog to work with from a recent standpoint.

Well here's an image of 2008 last year on Oct 10 to compare to the above pics

ims2008284.gif

I don't know the pixel counts though.

Link to comment
Share on other sites

Per Rutgers, snow cover:

2011 week 39: 9.49 million sq. km

2010 week 39: 7.69 million sq. km

2009 week 39: 6.32 million sq. km

2008 week 39: 6.86 million sq. km

2007 week 39: 7.16 million sq. km

2006 week 39: 6.12 million sq. km

2005 week 39: 9.25 million sq. km

2004 week 39: 6.56 million sq. km

2003 week 39: 7.77 million sq. km

2002 week 39: 10.75 million sq. km

2001 week 39: 9.49 million sq. km

2000 week 39: 12.54 million sq. km

2011 currently stands as the 10th highest snow cover since 1967

1977 15.1

1972 14.11

2000 12.54

1973 11.52

2002 10.75

1989 10.54

1983 10.23

1986 9.88

1979 9.58

2011 9.49

Link to comment
Share on other sites

Per Rutgers, snow cover:

2011 week 39: 9.49 million sq. km

2010 week 39: 7.69 million sq. km

2009 week 39: 6.32 million sq. km

2008 week 39: 6.86 million sq. km

2007 week 39: 7.16 million sq. km

2006 week 39: 6.12 million sq. km

2005 week 39: 9.25 million sq. km

2004 week 39: 6.56 million sq. km

2003 week 39: 7.77 million sq. km

2002 week 39: 10.75 million sq. km

2001 week 39: 9.49 million sq. km

2000 week 39: 12.54 million sq. km

What dates are week 39? We did start off the first few days of October above average in 2011, but have gone below average since then. The opposite happened in '09 and '10 IIRC. I still think that 2011 number looks really high unless week 39 is the very end of September and first few days of October.

Link to comment
Share on other sites

What dates are week 39? We did start off the first few days of October above average in 2011, but have gone below average since then. The opposite happened in '09 and '10 IIRC. I still think that 2011 number looks really high unless week 39 is the very end of September and first few days of October.

Yeah, that makes more sense. It's September 26 to October 2.

They do look really high. See what I added to the post. 2011 is in TENTH place since 1967

Link to comment
Share on other sites

Yeah, that makes more sense. It's September 26 to October 2.

They do look really high. See what I added to the post. 2011 is in TENTH place since 1967

That makes perfect sense. It definitely was doing well in that week but since then has gone south. I'm sure week 40 will come in negative in anomalies.

Link to comment
Share on other sites

ims2004286.gif

2004 has the maps we use now.

Snow: 3,683

Ice: 2,152

ims2005285.gif

Snow: 3,045

Ice: 1,806

ims2006285.gif

Very interesting to see the differences in how far south the snow extends and where it isn't. I wish I could overlay which year was El Nino/La Nina... that would be interesting to see.

Snow: 4,647

Ice: 1,934

ims2007285.gif

WOW! Look at 2007!

Snow: 3,440

Ice: 1,532

ims2008286.gif

Interesting comeback for ice in 2008

Snow: 2,845

ice: 1,954

ims2009285.gif

2009 is interesting too... look at all of the early snow across the US!

Snow: 5,941

Ice: 1,967

ims2010285.gif

Snow: 4042

Ice: 1964

ims2011285.gif

Snow: 3,031

Ice: 1,787

In conclusion, this year, compared to past years at this times is not nearly as active as it was in 2009, but is nowhere near as bad as it was in 2007. I didn't post 1997 - 2003 because the snow pixel counts were wayyyy too high. The maps were different back then and I wouldn't know how to properly deduct the noise from the snow.

Link to comment
Share on other sites

2009 had a huge end of October (last week of the month if memory serves) so today being the 13th w/a deficit isn't a big deal

in fact, I think 2009 had a big drop in NOV to decently below average and then came right back above

True, but look at 2007. Did we even have a winter in 2007-2008?

Link to comment
Share on other sites

True, but look at 2007. Did we even have a winter in 2007-2008?

NE did, but those of us in the MA didn't, except for a clipper in early DEC

I'm as big a snow weenie as anyone here, but it's early in my mind

sure, I'd like to see blockbuster snow over Siberia now, but that never happens, even in the great winters

actually, I'm liking the look of the placement of the snow cover this year on the other side of the NP in that there's snow cover developing north of the Caspian, similar to 09', but not quite to the extent.........yet?

Link to comment
Share on other sites

Snow cover currently is below normal and despite the models showing some gains across Siberia, I think October may come in slightly below normal still. I think we should focus our attention on the ENSO more than the Siberian Snow Cover at this point given the link between Fall NH snowcover is not always a guarantee the following Winter. I mean in 2006 the snowcover was above average in October but look how the WInter turned out that year :rolleyes:....it didnt even get get started till Jan 15th lol. I mean given my location I only got about 2-4" in December, WAY below the average.

As for the NAO the models develop a West Based NAO for a while before the models shift there attention a bit more east (East Based blocking). West Based blocking often means the PV is situated across Northern Canada with a strong HP anomaly across Greenland and LP anomalies across Eastern Siberia but we'll see.

http://raleighwx.americanwx.com/models/12zwestNAOcomparison.html

http://raleighwx.americanwx.com/models/12zeastNAOcomparison.html

Link to comment
Share on other sites

Snow cover currently is below normal and despite the models showing some gains across Siberia, I think October may come in slightly below normal still. I think we should focus our attention on the ENSO more than the Siberian Snow Cover at this point given the link between Fall NH snowcover is not always a guarantee the following Winter. I mean in 2006 the snowcover was above average in October but look how the WInter turned out that year :rolleyes:....it didnt even get get started till Jan 15th lol. I mean given my location I only got about 2-4" in December, WAY below the average.

As for the NAO the models develop a West Based NAO for a while before the models shift there attention a bit more east (East Based blocking). West Based blocking often means the PV is situated across Northern Canada with a strong HP anomaly across Greenland and LP anomalies across Eastern Siberia but we'll see.

http://raleighwx.ame...comparison.html

http://raleighwx.ame...comparison.html

It's a useful correlation but like everything in meteorlogy, needs to be utilized in combination with other factors in order for significant use to be gained from it.

Link to comment
Share on other sites

I've never been convinced snowcover in october means much of anything toward the wintertime NAO, but rather the NAO phase seems to be the biggest contributor in what builds the snowcover up early, I recall last fall a loss in snowcover in the late fall before recovering significantly as the -NAO developed.

Link to comment
Share on other sites

I've never been convinced snowcover in october means much of anything toward the wintertime NAO, but rather the NAO phase seems to be the biggest contributor in what builds the snowcover up early, I recall last fall a loss in snowcover in the late fall before recovering significantly as the -NAO developed.

There are several peer reviewed articles suggesting you are wrong. Here are a few of them.

http://journals.ametsoc.org/doi/abs/10.1175/2008JCLI2505.1

http://journals.ametsoc.org/doi/abs/10.1175/JCLI4241.1

http://www.nws.noaa.gov/ost/climate/STIP/FY11CTBSeminars/jcohen_062211.pdf

The fall snow cover certainly isn't the only thing to to consider but is something to look at.

Link to comment
Share on other sites

There are several peer reviewed articles suggesting you are wrong. Here are a few of them.

http://journals.amet.../2008JCLI2505.1

http://journals.amet...1175/JCLI4241.1

http://www.nws.noaa....ohen_062211.pdf

The fall snow cover certainly isn't the only thing to to consider but is something to look at.

come on Wes, when you live in the MA, you can't succumb to peer pressure when it goes against us getting snow :wacko:

Link to comment
Share on other sites

There are several peer reviewed articles suggesting you are wrong. Here are a few of them.

http://journals.amet.../2008JCLI2505.1

http://journals.amet...1175/JCLI4241.1

http://www.nws.noaa....ohen_062211.pdf

The fall snow cover certainly isn't the only thing to to consider but is something to look at.

Thanks. Definitely not saying it has no effect or can't enhance/create feedbacks between the two, [[NAO and resulting snowcover, + visa versa]], but I think there is a difference between correlating snowcover to the NAO and finding the chicken or the egg, a mechanism & it's relative forcing versus other drivers.

Admittedly I only looked at one of the papers you linked because I'm stripped for time, but it references a model using the October Snowocover anomaly to predict the winter NAO state, and as far as I read didn't see a detailed description of the mechanism at work, and it's forcing on the NAO versus other drivers.

I may be wrong I'll need to do more research on the subject, just my opinion. In January 2011 the snowcover state clearly favored the -NAO through the winter and yet the NAO flipped positive mid-winter and never returned negative until late spring, so I feel there are more powerful forcings driving the NAO than snowcover that may be a result of the NAO itself rather than a forcing, or perhaps a feedback connection exists between the two...I don't know.

Link to comment
Share on other sites

Thanks. Definitely not saying it has no effect or can't enhance/create feedbacks between the two, [[NAO and resulting snowcover, + visa versa]], but I think there is a difference between correlating snowcover to the NAO and finding the chicken or the egg, a mechanism & it's relative forcing versus other drivers.

Admittedly I only looked at one of the papers you linked because I'm stripped for time, but it references a model using the October Snowocover anomaly to predict the winter NAO state, and as far as I read didn't see a detailed description of the mechanism at work, and it's forcing on the NAO versus other drivers.

I may be wrong I'll need to do more research on the subject, just my opinion. In January 2011 the snowcover state clearly favored the -NAO through the winter and yet the NAO flipped positive mid-winter and never returned negative until late spring, so I feel there are more powerful forcings driving the NAO than snowcover that may be a result of the NAO itself rather than a forcing, or perhaps a feedback connection exists between the two...I don't know.

It's the fall snow cover that is important not the winter. There diefinitely are lots of other factors, solar, tropical forcing, stratospheric warming events and downwelling, the Atlantic that also have an imfluence on it along with wave breaking of synoptic scale waves. That's why many climo people say it is not possible to forecast the nao more that a week or so in advance.

Link to comment
Share on other sites

It's the fall snow cover that is important not the winter. There diefinitely are lots of other factors, solar, tropical forcing, stratospheric warming events and downwelling, the Atlantic that also have an imfluence on it along with wave breaking of synoptic scale waves. That's why many climo people say it is not possible to forecast the nao more that a week or so in advance.

This is all true about the assumption, but the longer timescale monitoring - tracking the index for multiple decades - shows a about 30 year periodicity of mode tendency. It may be possible to infer a -NAO or +NAO bias "potential" based on upon where we happen to be along that curve. ...with risk of course..

Link to comment
Share on other sites

It's the fall snow cover that is important not the winter. There diefinitely are lots of other factors, solar, tropical forcing, stratospheric warming events and downwelling, the Atlantic that also have an imfluence on it along with wave breaking of synoptic scale waves. That's why many climo people say it is not possible to forecast the nao more that a week or so in advance.

Ah, thanks, really appriciated. I'm wondering though, if fall snowcover is a driver of the -NAO for the following winter, why wouldn't winter snowcover matter if it is the same supposed mechanism acting on the block? I guess thats what confuses me, that winter snowcover wouldn't mean anything but fall snowcover somehow means something more substantial.

Sometimes I wonder if it is the -NAO in the first place that is sparking an increase in NH snowcover, rather than the other way aroun. In the winter I know that is the case but in the fall it would make sense as well, unless I'm missing something in which case forget everything I just said :rolleyes:

Link to comment
Share on other sites

This is all true about the assumption, but the longer timescale monitoring - tracking the index for multiple decades - shows a about 30 year periodicity of mode tendency. It may be possible to infer a -NAO or +NAO bias "potential" based on upon where we happen to be along that curve. ...with risk of course..

NAO, AMO, PDO, and to some extent, the AO, all 30 year cycles. Coincidence?

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...