« Powerpoint for Jan 9th meeting | Main | Interesting Analysis....some questions »

January 10, 2008

Interesting Analysis....some questions

thanks, Cathy.

Remind me of how much snow Mammoth Mtn got?  Also, it would be nice to make the composite January Mammoth
snowfall for the historical La Ninas. 

Jan.  1955, 65, 71, 73, 84, 89, 96, 99.

These may differ from your list of years.

The above list is from Klaus Wolter...yr 0 analogue cases.

marty

Posted by csi at 10:18 PM | | TrackBacks (0)

Snowfall in CA in Jan

I was curious about the heavy snowfall in CA and whether there was any relationship to SST (La Nina, other). So, I found the 10 snowiest Mammoth Lakes snowfalls from 1968 onwards. 


I then composited them with a few different SST datasets.The heavier snowfall does seem to be associated with increased SST's near the western pacific (Japan).sst.mammoth.png








I excluded the later snowy years and got a similar plot but without the Atlantic SST anomalies but still with the western Pacific SST anomalies. I then looked at some other variables including 500mb heights hgt500.mammoth.png. There does seem to be a wavetrain possibly originating from that region of the Pacific.
I didn't include this year though it most likely will have one of the top 10 snowfalls in Mammoth. Certainly there are warm SST's in that region for this year (Dec).

Cathy

Posted by MTAdmin at 9:44 PM | | TrackBacks (0)

January 8, 2008

Powerpoint for Jan 9th meeting

Here is the Jan 9th Powerpoint presentation for the meeting.
IAP_9JAN2008.ppt

Posted by MTAdmin at 10:17 PM | | TrackBacks (0)

December 20, 2007

Just a note about posting...

Please note that you should be logging into this blog as the "csi" user to write entries. This can be confusing because you sometimes may need to log in twice, depending on the state of your Web browser.

Typically what you should see is this:
1) You open your browser with the blog URL: http://www.esrl.noaa.gov/psd/programs/climate_csi/
2) You click the "Add Entry" link.
3) A log-in screen appears. Sometimes you may have to log-in twice:
If this screen does not have the Movable Type logo, then you are being asked for your NEMS username and password (your NOAA e-mail username and password).
If this screen does have the Movable Type logo, log in as the csi user, with the password that was mailed to you.
4) Save the post. status=unpublished saves it but means no one will see it. you can edit it more. Save as published when you are are totally done.

Cathy and Greg

Posted by csi at 5:02 PM | | TrackBacks (0)

December 19, 2007

What's Leading What?

An inspection of the PMEL analysis of the Pacific water volume anomalies (a measure of ocean heat content) indicates a most curious behavior of the Pacific Ocean temperatures during this La Nina. 

The figure I'm looking at is our attribution toolbox:

http://www.cdc.noaa.gov/CSI/tools.html

Go to Current Conditions item 6, and select the Warm Water Volume: East vs West

In the PMEL analysis of the 25-yr history of water water volume anomaly, there have occurred 3 prior La Nina periods - roughly around 1984, 1988, 1999.  In all those, a (low) cold water volume anomaly in the west Pacific preceeds the low (cold) water volume anomaly in the east Pacific (and also the SST cooling of the eastern Pacific) by about 6 months or so from my read of the graph.

The current La Nina has seen no low (cold) water volume anomaly in the west Pacific, either as a precursor for this event in spring 2007, or as a current condition this Fall 2007.

The questions I'd like to toss out to CSI team for discussion are:

Q1: Is there something unique about the physical processes responsible for this La Nina relative to its prior 3 ancestors?

Q2: Has this differnence in antecdent Pacific basin conditions affected the predictability of this La Nina relative to its prior 3 ancestors?

Q3: What is the physical role of the antecedent water volume anomalies in the western Pacific for subsequent ENSO development (it seems to be neither a necessary nor a sufficient factor for ENSO development)

Q4: To my eye, there is a hint in the PMEL historical analysis that conditions of low water volume anomalies in the easterm  Pacific have a longer time scale than the opposite phased anomalies.  Is there reason, based upon current water volume condition, and historical events, to suspect that 2008 will be more likely La Nina rather than El Nina? (I note that many prediction models show this La Nina terminating in spring 2008)

Posted by Marty Hoerling at 7:57 PM | | TrackBacks (0)

December 5, 2007

Dec 5th meeting

A summary of the meeting may be put up on the blog.

Posted by David Enfield at 8:29 PM | | TrackBacks (0)