Upload
rodger-white
View
216
Download
2
Tags:
Embed Size (px)
Citation preview
Current Attribution Challenges•What is the origin of warm Atlantic SSTs in 2006/2007?
Std dev of annual variations= 0.25°C
Current Attribution Challenges•What is the origin of warm Atlantic SSTs in 2006/2007?
January 2007 SST Anomaly (NCEP)
Current Attribution Challenges• How do we explain the success/failure of seasonal outlooks?
December - February 2007 Outlook
Current Attribution Challenges• How do we explain the success/failure of seasonal outlooks?
December - February 2007 Outlook
Current Attribution Challenges• How do we explain the success/failure of seasonal outlooks?
February-April 2007 Outlook
‘Crashing’ El Niño composites & latest AMJ SWcasts more consistent with it
Klaus Wolter - 26feb07
• Size of Niño 3/3.4 drop since early December vs. other cases• T&P composites in U.S. for ‘crashing’ El Niños
• SWcasts for April-June are trending downward
Recent Niño time seriesThe 2006-07 El Niño is ‘crashing’ fast in key Niño regions 3 and 3.4. A drop of about 1C in two months is not completely unprecedented, however.
Analog years can be defined by requiring an initial (December) SST anomalies of 0.5-2.5C, followed by a 2-3 month drop of 1C (0.9C) for Niño 3 (3.4), respectively. Fastest drops were in 1964, 66, 73, and 03. Other cases used: 52, 70, 88, and 95.
Spring composite for ‘crashing’ El NiñosIf you superimpose warming trends in March (large in Western U.S.), March may be rated ‘EC’ for SW, warm elsewhere.
Compared to ‘regular’ El Niño Marches, this one is not as bullish about precip. It is ‘wet’ around here mainly due to 2003.
Spring composite for ‘crashing’ El NiñosMarch through May looks quite similar to March in temperature composites, possibly warmer in SE U.S.
Note the lack of moisture in New Mexico and Texas!
Spring composite for ‘crashing’ El NiñosClassic El Niño temperature associations (left), and abundant moisture for spring in southwest (bottom).
Spring composite for ‘crashing’ El NiñosTemperature-wise, still looks like classic El Niño (left), but one should superimpose the warming trend.
A vestige of above-normal moisture west of here, but mostly under +0.5 sigma, not significant!
Spring composite for ‘crashing’ El NiñosClassic El Niño temperature associations (left), and abundant moisture for spring in southwest (bottom) lingers into April-June.