Jump to content
  • Member Statistics

    17,611
    Total Members
    7,904
    Most Online
    NH8550
    Newest Member
    NH8550
    Joined

Stratospheric Warming event on the way?


Recommended Posts

  • Replies 404
  • Created
  • Last Reply

For those who think the warming has made much of a difference. Here's a chart from the japanese showing the 30 mb temps compared to normal. They are way below normal. The slight spike with the warming quickly was beat down. The winds are strongly westerly. I'm no expert but as HM has noted. SSW events aren't that common and with the temps so cold it's a stretch to think one is on the immediate horizon (at least that's my view).

post-70-0-05158300-1324044449.gif

Does that completely say there can be no blocking, no. Most likely for us any blocking would start in AK or siberia.

Link to comment
Share on other sites

For those who think the warming has made much of a difference. Here's a chart from the japanese showing the 30 mb temps compared to normal. They are way below normal. The slight spike with the warming quickly was beat down. The winds are strongly westerly. I'm no expert but as HM has noted. SSW events aren't that common and with the temps so cold it's a stretch to think one is on the immediate horizon (at least that's my view).

post-70-0-05158300-1324044449.gif

Does that completely say there can be no blocking, no. Most likely for us any blocking would start in AK or siberia.

I agree with you, Wes.

So far, IMO no SSW is imminent. Each modest attempt at warming has been reversed to date. Many winters don't experience such events, so expectations for such an event probably should be restrained unless there is strong evidence that such an event is likely.

Link to comment
Share on other sites

Where do we get these temps from ? sats? Weather balloons? Real time OBS? Model extrap?

Most of the products that are shown are from gridded analyses (global model initial conditions, though likely from the late-cutoff runs). So it's a combination of a short term (06-h) forecast and corrections from observations (rawindsonde/balloons and quite a bit of satellite data [MW/IR radiances] including GPS radio occultation data).

Link to comment
Share on other sites

Most of the products that are shown are from gridded analyses (global model initial conditions, though likely from the late-cutoff runs). So it's a combination of a short term (06-h) forecast and corrections from observations (rawindsonde/balloons and quite a bit of satellite data [MW/IR radiances] including GPS radio occultation data).

Daryl thanks, I was just getting the Japanese explanation when you posted and it pretty much says the same thing. The product I posted was from there gridded analyses.

http://ds.data.jma.go.jp/tcc/tcc/products/clisys/STRAT/html_e/readme.html

Link to comment
Share on other sites

For those who think the warming has made much of a difference. Here's a chart from the japanese showing the 30 mb temps compared to normal. They are way below normal. The slight spike with the warming quickly was beat down. The winds are strongly westerly. I'm no expert but as HM has noted. SSW events aren't that common and with the temps so cold it's a stretch to think one is on the immediate horizon (at least that's my view).

post-70-0-05158300-1324044449.gif

Does that completely say there can be no blocking, no. Most likely for us any blocking would start in AK or siberia.

This chart looks out of date, for this week. These charts show more recent spike in temps occurring 10hpa and 30hpa. The 10hpa temps are getting within majority spread:

You go this site, to find these maps, and you will see recent spike occurring on in their higher latitudes right now. The average temp between 60-90N, has shown a recent spike as well:

http://acd-ext.gsfc....t/ann_data.html

However, I don't also believe this is a major SSW yet and I am concerned about the Euro forecast changes with the EP flux, that this warming won't fully propagate into the troposphere. Not in time, for a major change in late Dec or early Jan.

Link to comment
Share on other sites

For those who think the warming has made much of a difference. Here's a chart from the japanese showing the 30 mb temps compared to normal. They are way below normal. The slight spike with the warming quickly was beat down. The winds are strongly westerly. I'm no expert but as HM has noted. SSW events aren't that common and with the temps so cold it's a stretch to think one is on the immediate horizon (at least that's my view).

post-70-0-05158300-1324044449.gif

Does that completely say there can be no blocking, no. Most likely for us any blocking would start in AK or siberia.

The warming that has been talked about in this thread is at the 1 and 5 hpa level at t240 so

it will be a while yet before we see any response at the 30 hpa level. At least this is what I

think Chionomaniac has been refering to.

Link to comment
Share on other sites

The warming that has been talked about in this thread is at the 1 and 5 hpa level at t240 so

it will be a while yet before we see any response at the 30 hpa level. At least this is what I

think Chionomaniac has been refering to.

As Don and I mentioned, even if it makes it to 30 mb and the winds at that level reverse and we're way away from taht now, there is no guarantee even with a ssw event that the AO and nao will go negative. Much depends on the EP flux. SSW events are not that common, minor warming events like the past one are. As to the chart that showed the spike downward in temps stopping, the temps still were way below normal.

Link to comment
Share on other sites

But I thought you believed the AP geomagnetic index was the primary solar driver for blocking? That has been very low for quite awhile.

Ap values were surging over 10 (up to 60 one day) quite a few times before November, which in conjunction with high solar flux likely aided in the +AO/NAO. Since late Nov, the Ap has been consistently back below 5 and the solar flux down from 180 to 120 now.

Link to comment
Share on other sites

Ap values were surging over 10 (up to 60 one day) quite a few times before November, which in conjunction with high solar flux likely aided in the +AO/NAO. Since late Nov, the Ap has been consistently back below 5 and the solar flux down from 180 to 120 now.

have you looked at the 12/16 5mb and 10mb maps for days 8-10 at the Berlin site?

quite a warming predicted that begins day 8 and is going full blast by day 10

hopefully, it will work its way down

http://www.geo.fu-be...tics/index.html

Link to comment
Share on other sites

I think that it is a patient waiting game stratospheric wise presently. We are seeing an extremely cold stratosphere slowly giving way to remote tropsospheric wave breaking, a slow increase in ozone levels and a reduction in the residual westerly QBO at lower tropical stratospheric levels.

All this will slowly turn around unfavourable stratospheric conditions to something more favourable with or without a SSW by the second half of winter. No quick switch around is likely unless we see a split SSW.

Of interest is that the last few long range GFS runs have suggested a warming over the North Pole at T+384 at 1hPa with the cold air totally displaced. If this was to occur then the vortex at this level would be seriously compromised.

Link to comment
Share on other sites

...during easterly QBOs

You're referencing the 11 year sunspot cycle, right? I was attempting to reference the background solarcharged wind speed and density specifically, which did not drop to extremely low values until sometime in 2009 and remained very weak until spring 2011 I believe, correct me if I have the wrong date.

I figure thats why there was no extreme blocking until it crashed in 2009, despite the overall minimum in 2008, as well as the -NAO in 2010/11 occuring during the period of weaker charged winds.

Link to comment
Share on other sites

You're referencing the 11 year sunspot cycle, right? I was attempting to reference the background solarcharged wind speed and density specifically, which did not drop to extremely low values until sometime in 2009 and remained very weak until spring 2011 I believe, correct me if I have the wrong date.

I figure thats why there was no extreme blocking until it crashed in 2009, despite the overall minimum in 2008, as well as the -NAO in 2010/11 occuring during the period of weaker charged winds.

I was actually referencing the papers in academic journals that show SSWs are more favorable with a weak sun during easterly QBOs and with an active sun during westerly QBOs.

Link to comment
Share on other sites

I was actually referencing the papers in academic journals that show SSWs are more favorable with a weak sun during easterly QBOs and with an active sun during westerly QBOs.

Here's one of the articles that you are referring to. I think I've posted this before for Bwx but maybe my memory is tricking me.

http://journals.ametsoc.org/doi/pdf/10.1175/JAS-3297.1

Link to comment
Share on other sites

I was actually referencing the papers in academic journals that show SSWs are more favorable with a weak sun during easterly QBOs and with an active sun during westerly QBOs.

But what aspect of the Sun are you alluding to? The 11 year TSI cycle I presume? Bunching TSI together with the solarcharged winds might scew the effect the they had in 2010/11 despite the +QBO. Even though there was no big difference in TSI from previous minimums the charged particle winds fell to all time lows in 2009 into early 2011 which is when we saw all of our extreme blocking.

Link to comment
Share on other sites

In the long-range, one is seeing a shrinking of the area of warm anomalies and deepening cold ones. That could be an indication of a lack of blocking in the long-range. If the long-range forecast plays out, the polar vortex would strengthen anew and a strong AO+ regime would reassert itself. That would increase prospects for warmth in the East, especially if a PNA- setup is in place.

That last map was from 10mb not 1mb. Big difference. I only posted it to show that the warming actually downwells as opposed to staying up at 1mb.

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...