* UK rainfall totals 1,330.7mm in 2012
* More intense rainfall has become more frequent
LONDON Jan 3 (Reuters) - Britain in 2012 experienced its second wettest year since records began in 1910 and extreme rainfall has become more frequent, the UK's Met Office said on Thursday.
Persistent wet weather resulted in total rainfall of 1,330.7mm in 2012, just 6.6mm short of the record set in 2000, data from the Met Office showed.
The environment agency said over 7,000 properties were affected by floods in 2012.
"We have always seen a great deal of variability in UK rainfall because our weather patterns are constantly changing," it said in a statement.
"However, preliminary evidence suggests we are getting slightly more rain in total and it may be falling in more intense bursts."
Annual rainfall has increased by around 5 percent over the 30-year periods 1961-1990 to 1981-2010. Preliminary research also suggests "extreme" days of rainfall have become more frequent since 1960.
Changes in sea-surface temperatures, melting Arctic sea ice and rising global temperatures could all be influencing Britain's rainfall patterns but more research needs to be done on the role they play, the Met Office said.
A warmer atmosphere can hold more moisture, therefore increasing rainfall. There has been an increase of around 0.7 degrees Celsius in global temperatures since pre-industrial times.
This could equate to about a 4 percent increase in moisture in the atmosphere, the Met Office said.
The Met Office forecast in December that 2013 could be one of the warmest on record worldwide, with global temperature expected to rise 0.57 degrees above the long-term average of 14 degrees.
"The trend towards more extreme rainfall events is one we are seeing around the world, in countries such as India and China, and now potentially here in the UK," said Julia Slingo, the Met Office's Chief Scientist.
"It's essential we look at how this may impact our rainfall patterns going forward over the next decade and beyond, so we can advise on the frequency of extreme weather in the future and the potential for more surface and river flooding." (Reporting by Nina Chestney; editing by Keiron Henderson)