* 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, melt