by Richard Kool
HERE on the west coast, we're having a very mild winter. Central Canada has had unprecedented ice storms. Snow in Mexico. Weird weather everywhere. What's going on? Blame it on El Nino!
Looking even more intense than the "event of the century" in 1982, this year's El Nino is having a worldwide impact. What scientists formally call El Nino Southern Oscillation (ENSO) is an unusual pattern of sea surface temperature (SST) that originates in the southern Pacific. In effect, warm water is pumped into places where it normally isn't. The water temperature at the equator off of South America, for example, can be 5 degrees C warmer than normal and the sea level may rise as much as 0.5 metres. What results is a range of odd climatic disturbances, from droughts in the Canadian prairies to the collapse of Peruvian fisheries. And you can find out all about it on the net.
Where to begin? I'd start at the El Nino Theme Page (1) brought to us by the good folks at the U.S. National Oceanographic and Atmospheric Agency. Their Frequently Asked Questions is a good gateway into the site, but don't stop there because there is some really amazing stuff in store if you've got a good connection to the net and the right software. For example, I was amazed by a set of animations (2) that show the changes in SST over the course of the last four El Nino events, in 1982, 1991, 1994 and 1997. What is interesting here is to see that the 1997 El Nino is obviously more intense than previous ones, with the pool of warm water starting earlier and extending much further. This site is rich with up-to-date satellite images (3), current data from an array of buoys moored in the tropical Pacific, graphs, charts, text, links and more. It is the place that teachers and students should start from as they try to understand what is happening.
For a site that offers good educational materials about the El Nino, take a spin to the El Nino/Earth Science Virtual course. (4) Intended for junior high and up, this site is very clear and easy to navigate. It includes an on-line library of articles and books (although not all the links worked for me) that should help anyone interested in the subject find out more. Links to data sites also can be found here.
While it is clear that the U.S. government has a huge investment in the science of El Nino, this isn't to say that the Canadians are doing nothing. Environment Canada has a very interesting site, (5) available in both official languages, offering a Canadian perspective on the subject. Data similar to that found in the U.S. pages are here, including a very easy-to-find daily SST map. But what makes this of special interest to those North of 49 degrees is that you can go to any region of Canada and find current predictions of the implications of El Nino for that region.
Why are we seemingly getting more frequent bouts of weird weather? Many scientists attribute a great deal of the increasing variability of the weather to global climate change caused by rising levels of greenhouse gases. For more on this, take a look at the Teachers' Guide to Global Change, produced by the Royal Society of Canada's Canadian Global Change Program (6) (available in English and French). And to see what the world community might be doing about those greenhouse gases, the Kyoto conference home page will give you the information you're looking for. (7)
Seven sites for warm seas and weird weather
Richard Kool is the Interpretation and Education
Officer of BC Parks, British Columbia Ministry of Environment,
Lands and Parks, in Victoria, British Columbia. His address is
rkool@cln.etc.bc.ca