September was the month when the mass of warm water in the Pacific known as "El Nino" started to create severe problems. Here is the diary of a disaster.

1 September: Much of the Southern hemisphere began to appreciate the true extent of this year's Enso - the El Nino Southern Oscillation - an irregular and generally unpredictable warming of a mass of water in the Pacific which can have drastic effects on the climate of a large region. In 1982-83, El Nino claimed 2,000 lives and cost $13bn in damage and lost production. This year's, scientists predict, could be worse.

8 September: Measurements show that the warming of the Pacific is now four months ahead of the levels reached in 1982-83. Water temperature is exceeding all previous records and El Nino is now being widely described as "the climate event of the century". Prayer meetings are held in Indonesia for an end to the El Nino-induced drought threatening coffee crops. Images of the Christ Child (after whom El Nino is named, because it peaks around Christmas) are carried into rice and corn fields for special prayers.

11 September: A government farming adviser in New Zealand warns that crop and livestock losses due to drought could exceed pounds 80m. On the New York stock exchange, coffee and cocoa prices rise sharply. Fish experts in California warn of possible drastic depletion of salmon and other fish stocks.

14 September: Drought and famine are reported in Papua New Guinea and in North Korea. Peru adjusts its economic forecast because of fears of coastal flooding and drought in mountainous regions.

16 September: Australia predicts that El Nino will cost it more than pounds 250m in lost exports by burning away millions of tons of the wheat crop.

15 September: Satellite readings show that the mass of warm water in the Pacific is now one-and-a-half times the size of the United States, having grown by 50 per cent since May. Experts are now calling it the worst El Nino for 150 years.

17 September: The expected Australian loss is adjusted upwards to pounds 300m. South Africa prepares for a drought.

20 September: Crop and livestock losses in New Zealand are reported to have exceeded pounds 80m. Roofing companies in California report strong business as winter torrents are predicted.

22 September: The Australian air force begins an airlift of supplies to Papua New Guinea. More than 250 have died of starvation and cholera in neighbouring Irian Jaya. US coffee prices rise again.

23 September: Peru discusses an emergency loan of $150m from the World Bank "to cover the expenses the government is incurring to face the El Nino phenomenon".

26 September: Indonesia's worst drought for 50 years worsens the effects of the smog-creating fires in the region.

30 September: The Maize Producers' Association of South Africa says an early El Nino drought could spell disaster for the region.

Finally, what of the UK? Some experts predict that the effects of El Nino will give us a cold, wet spring and summer next year. Others say our climate is so variable that any effect will be too small to notice. While the behaviour of the Pacific Ocean is fairly well understood, the Atlantic is still largely a mystery.