Atmospheric River Phenomena

It seems that our winter floods could be a significant part of our future. According to new research into powerful weather systems called "atmospheric rivers" which when first identified were described as "conveyor belts" of moisture. But now identified as atmospheric rivers. The atmospheric rivers are bands of moisture that flow through the air and are already known to be responsible for heavy rainfall. The new study suggests that warmer conditions could create even more atmospheric rivers and make them even more severe. 

The paper is published by the Institute of Physics in Environmental Research Letters.

Atmospheric rivers are described as being up to 300 km wide and can stretch in length for between 1,000 to 2,000 km. They flow invisibly between 1 and 2.5km above the surface of the ocean. Atmospheric river is believed to have been behind the violent flooding that hit Cockermouth in Cumbria on 19 November 2009. The flooding claimed the life of a policeman, who died after a bridge collapsed. The researchers, led by Dr David Lavers of the University of Iowa, have estimated the staggering volume of moisture carried by this particular atmospheric river. They calculate that at its peak it was transporting almost 300,000 tonnes of moisture every second. Which is 4600 times more than the River Thames which carries by comparison 65 tonnes of water through London every second.

Over the last 30 years, there has been an average of 9 to 11 of the strongest atmospheric river events hitting Britain every year. In this latest study, the researchers examined five different modelling scenarios to simulate possible conditions this century and found that a warming climate - which allows the atmosphere to hold more moisture - made the atmospheric rivers more likely.

Dr Lavers said: "All five models suggest that there could be a doubling of atmospheric river events. Most of those could be expected to make landfall in the UK. One of the big things is that these are the most relevant feature of winter flooding in Britain and the work is certainly suggesting an increase in strength and frequency."

Time to buy shares in umbrella makers me thinks!