El Nino brings unusual start to the year for many

The world has entered 2016 with a major El Nino event in place.

This one has changed the weather globally in a year that already looks like the warmest yet recorded.

El Nino is the gathering of warm water in the central, then eastern equatorial Pacific, with its gradual banking up against the coast of the Americas.

It is an irregular event but one with dramatic consequences to the weather for most countries on earth.

This is because it has the effect of moving the areas of major evaporation, therefore cyclone formation, eastwards by about 60 degrees.

That means all the seasonal dry areas follow suit, and we end up with unusually heavy rains for some, heatwaves for others. Droughts and storms occur more often than normal.

This El Nino event stands at the moment as the third strongest, following 1997 and 1982, since reliable records started being kept in 1950.

Typically there are about three events per decade, but most are not major in their influence.

As 2016 starts, there are significant floods in South America, the United States and the United Kingdom.

Skiers are despairing at the lack of snow in the European Alps and enjoying the first sight of it in the New England resorts of the US. Meanwhile, drought prevails in Southern Africa and Amazonia.

In many places then, January 1 2016 was greeted in unusual conditions:

• Istanbul, Turkey was shut down by snow.
• St Louis, Missouri in the US was partly underwater as the the Mississippi River, the Missouri River and their tributaries overflowed following unprecedented December rain.
• Canberra, Australia recorded 35C, a good seven degrees above normal and a reflection of the severe heatwaves that have introduced Australia’s summer.
• Washington DC finally dropped to its average of 6C after enjoying temperatures in the 20s, along with all of the eastern US, just a week before.
• London, England recorded 10C, still above average, in a country that has seen an excess of mild, wet and stormy weather so far this winter. The city of York is in flood.
• Doha, Qatar felt warm again at 26C, when only a week before, 40mm of rain kept temperatures below 20C.
• New Delhi, India, was warm enough at 25C but air quality remained poor with visibility in smog typically between 200m and 900m.
• Beijing too has been suffering badly from settled winter weather trapping pollution. Only a week before a red alert for poor air quality was issued – the second ever to be issued.
• At 26C, Wellington, New Zealand enjoyed a surprisingly warm day, 6C above the average.
• The on-and-off heatwave in South Africa was still reflected in Pretoria’s 34C. This is 6C above average and generated an evening thunderstorm, not enough to relieve the drought. During an El Nino event, South Africa is prone to drought. 

This year has a head start at being another in the continuing series of “warmest year recorded”.

The El Nino event has probably just peaked but will likely last through the first quarter of the year. Expect more unusual weather, but maybe with a return to the seasonal norm by the end of the year.