According to the The Bureau of Meteorology in the annual climate statement for 2010 released on January 5, 2010:
Based on preliminary data (to November 30), sea surface temperatures in the Australian region during 2010 were +0.54 °C above the 1961 to 1990 average. This is the warmest value on record for the Australian region. Individual high monthly sea surface temperature records were also set during 2010 in March, April, June, September, October and November. Along with favourable hemispheric circulation associated with the 2010 La Niña, very warm sea surface temperatures contributed to the record rainfall and very high humidity across eastern Australia during winter and spring. The most recent decade (2001−2010) was also the warmest decade on record for sea surface temperatures following the pattern observed over land.
According to the European Environment Agency "Global sea surface temperature is approximately 1 degree C higher now than 140 years ago, and is one of the primary physical impacts of climate change."