RECORD-breaking winter rainfall that led to devastating flooding across Hampshire has been blamed on unusual weather patterns in the tropics, writes Andy Simmonds.

Experts at the Met Office and scientists at the University of Oxford analysed weather systems around the globe relating to winter 2013-14 and they’ve concluded that conditions in the tropics and stratospheric wind patterns were largely responsible for creating the intense and persistent storms that battered Britain from December 2013 until mid-February 2014.

As a result of the constant deluges much of the UK experienced severe flooding stretching from Scotland in the north to England’s south coast.

The team of experts behind the report add that climate change also had a role to play in creating the extremely soggy conditions - albeit secondary.

Lead author of the report - published in the journal Environmental Research Letters - Jeff Knight, said: “During winter 2013-14, there was very heavy rainfall over the Western Amazon, even greater than usual. This effectively created a disturbance to high-level wind patterns that propagated outwards from the tropics. At the UK’s attitude, it resulted in a southward kink in the jet stream that was very long-lived and brought storm after storm across the country.”

Conditions in the stratosphere, the layer of atmosphere above the weather, had the effect of enhancing westerly winds blowing in rain-bearing weather systems from the North Atlantic across the UK, say the study’s authors.

Mr Knight pointed out that the 10 authors of the study looked at the role climate change may have had on the high rainfall that winter by reconstructing historical data based only on daily sea level air pressure patterns and comparing it with 2013-14’s data.

“By comparing rainfall amounts and pressure maps for every winter day for the last century or so, we can work out what rainfall to expect from any given pressure pattern. Then we can see if the actual recorded rainfall is different to what we infer,” explained Mr Knight.

Romsey, King’s Somborne, Hambledon and Winchester were some of the worst areas affected by flooding in Hampshire. Homes, business and roads in the Greatridge area of Romsey were submerged. Some residents were forced to abandon their homes until water levels subsided and were unable to return until their properties dried out months later. Troops were drafted in to build a barrier known as a ‘catflap’ across the Fishlake Stream at Greatbridge to slow down the flow in a bid to divert huge volumes of water into nearby meadows and down other River Test tributaries to prevent the whole town being flooded. Fire crews also placed a water-retaining barrier across the A3057 on the north-side of the Greatbridge Road viaduct. Both devices did their job - stopping Romsey vanishing under billions of tons of water. During the winter months 2013/14 an unprecedented amount of rain fell on the town smashing all records dating back more than 100 years.

Rainfall data, provided by the Environment Agency from the Government body’s gauge at the organisation’s Romsey office, shows it was an extremely wet period during the period December 1 2013 to March 1 2014 with a total of 703.2mm falling. This was almost thrice the average expected.

Besides Hampshire, neighbouring Wiltshire and Berkshire were both badly hit by the floods- particularly the Thames Valley.

And the Somerset Levels were turned into a swamp for several months with the depth of water several metres. Farm livestock were drowned in fields where the animals grazed because farmers were unable to reach them and the only way of getting about was by boat.