Thus spoke Bill Patzert, an oceanographer and climatologist at NASA’s Jet Propulsion Laboratory, Pasadena, California on Sep 28. 2009:
A macho El Niño like that of 1997-1998 is off the board, but I’m hoping for a relaxation in the tropical trade winds and a surprise strengthening of El Niño that could result in a shift in winter storm patterns over the United States. If the trade winds decrease, the ocean waters will continue to warm and spread eastward, strengthening the El Niño. That scenario could bring atmospheric patterns that will deliver much-needed rainfall to the southwestern United States this winter. If not, the dice seem to be loaded for below-normal snowpacks and another drier-than-normal winter…Don’t give up on this El Niño. He might make a late break and put his spin on this fall and winter’s weather systems
Wait a moment…so now a non-weak El Niño is good? Is this the first time anybody has said anything positive about El Niño?
No, it isn’t. Still, the ENSO has often been described as some kind of scourge. For example, here’s an article from The Independent on Jan 1, 2007:
A combination of global warming and the El Niño weather system is set to make 2007 the warmest year on record with far-reaching consequences for the planet, one of Britain’s leading climate experts has warned.
Professor Jones said the long-term trend of global warming – already blamed for bringing drought to the Horn of Africa and melting the Arctic ice shelf – is set to be exacerbated by the arrival of El Niño, the phenomenon caused by above-average sea temperatures in the Pacific.
The WMO said its latest readings showed that a “moderate” El Niño, with sea temperatures 1.5C above average, was taking place which, in the worst case scenario, could develop into an extreme weather pattern lasting up to 18 months, as in 1997-98. The UN agency noted that the weather pattern was already having “early and intense” effects, including drought in Australia and dramatically warm seas in the Indian Ocean, which could affect the monsoons. It warned the El Niño could also bring extreme rainfall to parts of east Africa which were last year hit by a cycle of drought and floods
And from a brochure published the UK’s Met Office in Nov 2006:
Dry spells are not unusual in the Amazon, but normally occur in El Niño years.
[...] the large number of Indonesian fires and associated increase in carbon emissions during the 1997-1998 El Niño event
And the IPCC (TAR)? Here it is:
El Niño is associated with dry conditions in northeast Brazil, northern Amazonia, the Peruvian-Bolivian Altiplano, and the Pacific coast of Central America. The most severe droughts in Mexico in recent decades have occurred during El Niño years, whereas southern Brazil and northwestern Peru have exhibited anomalously wet conditions
More recently, from the IPCC’s AR4, WG2, chapter 1:
After the accelerated shrinkage of the glacier during the 1990s, enhanced by the warm 1997/98 El Niño, Bolivia lost its only ski area