On Oct 26, 3:50 pm, Dawlish wrote:
Monday ENSO update from NOAA.
*El Niņo is present across the equatorial Pacific Ocean.
*Sea surface temperatures (SST) were at least 1.0ēC above-average
across much of the central and east-central equatorial Pacific.
*Based on current observations and dynamical model forecasts, El Niņo
is expected to strengthen and last through Northern Hemisphere winter
2009-10.
The El Nino is beginning to strengthen and most models go for a
significant strengthening through November/December, due to a Kelvin
wave bringing warmer water eastwards along the equator, as the
equatorial easterlies have weakened considerably over the past two
weeks. After that, most models have the El Nino persisting through the
boreal winter and through the spring, but only a few forsee
significant strengthening of the El Nino after December.
The ENSO SST pattern, with recent warming in regions 1 and 2 to
produce positive anomalies here looks to have a more of a "classic" El
Nino signature to me, than it has done in recent months, when Nino
areas 1&2 have shown negative anomalies.
The Australian BOM's update also highlights a strengthening El Nino.
The tropical Pacific Ocean sea surface remains warmer than average and
exceeds El Niņo thresholds in central to eastern regions. The central
Pacific has warmed further and now exceeds average values by the
largest amount since late 2006.
The sub-surface water of the tropical Pacific has warmed further in
central regions over the past two weeks, and now exceed 4°C above
normal in some regions.
The SOI has rapidly fallen through October with a current (26 October)
30-day value of approximately -12.
Trade winds have continued to weaken across the tropical Pacific in
the last two weeks. Weaker than normal Trade flow is now evident
across most of the equatorial Pacific.
Cloudiness near the date line has generally been greater than the long-
term mean over past months. However, when compared with other El Niņo
events, the current trend in cloudiness is weak.
Most leading international climate models surveyed by the Bureau
predict the tropical Pacific sea surface temperatures (SST) to remain
above El Niņo thresholds until at least early 2010.
http://www.bom.gov.au/climate/enso/