‘Unlikely’ El Nino offers hope for farmers. Or does it? by Elizabeth Saary
Australian weather forecasters have given hope to farmers today as the recent El Nino forecast sways towards a no show. The Bureau of Meteorology have stated that an El Nino event is now unlikely to occur this year despite the recent tell tale signs including drought and bush fires
El Niño is the disruption of the ocean-atmosphere system in the tropical Pacific. When in force it has dramatic consequences for weather around the globe.
During normal, non-El Niño conditions, the trade winds blow towards the west across the tropical Pacific. These winds push and pile-up warm surface water in the western Pacific, around Indonesia and Australia.
The sea surface temperature is therefore about 8 degrees Celsius higher in the west, off the coast of Australia, with lower temperatures in the east, off the coast of South America, due to an upwelling of cold water from deeper levels. This cold water is nutrient-rich and supports the diverse marine ecosystems and major fisheries.
The warmer water, off the Australian east coast, heats the air above it causing rapid ascent and forming storm clouds and rain. Australian farmers are dependent upon this rainfall in order to sustain healthy crops.
However during an El Nino year, the trade winds weaken, meaning that the warm waters are not pushed so far west. The rainfall then follows the warm water eastward, with associated flooding in Peru and drought in Indonesia and Australia. It also reduces the upwelling of cold, nutrient-rich water off the coast of South America, which affects the food chains and, in turn, the commercial fisheries.
So no wonder the Australian farmers are giving a huge sigh of relief at the news. The recent drought has given a large cause for concern, but now it seems that farmers will not have to worry until next year. Or do they?
Over on the other side of the Pacific, strange developments would seem rather contradictory to the news. Marine biologists are recording higher water temperatures, plummeting fish catches, dead birds on beaches, and very little plankton – the organisms vital to the ocean food chain – from California to British Columbia. Although slightly further north than usual, all of these signs would point towards El Nino and scientists have been left baffled, as Jane Lubchenco, a zoologist and climate change expert explains;
‘There are strange things happening, but we don’t really understand how all the pieces fit together.’
As to whether climate change is involved, again there is some scepticism;
‘It’s hard to say whether any single event is just an anomaly or a real indication of something serious happening.’
Whatever the reason, in an ever changing world, adaptation is the key to survival. Farmers and fishermen and many other industries, will have to change their working habits in order to cope with the inevitable changes of a volatile planet.
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