Climate CSI

'Convective' Variables

2008-02-12T23:00:09Z

You can look at some variables of interest in convection (lapse rate, CAPE...) at the webpage

http://www.cdc.noaa.gov/Composites/NSSL/Day/

What's nice about this page is that you can look at anomalies. We calculate these with the standard NCEP Reanalysis I Variables and so the resolution is lower than other sources. Still, looking at the Temperature lapse rate on Feb 5th, for example, it was much greater than is typical.

You can also select a day and plot N days before or after it. If you start some days before an event, you can create a plot for each day. If you set the variable range to be the same, then you can step through each plot using your browsers back/forward button creating a poor mans' movie.

email or call for questions.

Cathy

Interesting Analysis....some questions

2008-01-10T22:18:52Z

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

Snowfall in CA in Jan

2008-01-10T21:44:50Z

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.

http://www.mammothmountain.com/site_common/lib/pastyears.cfm

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).

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 . 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

Powerpoint for Jan 9th meeting

2008-01-08T22:17:32Z

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

Just a note about posting...

2007-12-20T17:02:18Z

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

What's Leading What?

2007-12-19T19:57:36Z

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)

Dec 5th meeting

2007-12-05T20:29:03Z

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