The world is on course for the hottest year since records began in 1880 after record-breaking temperatures in four of the first six months of the year, according to meteorologists.

The first six months of 2010 brought a string of warmest-ever global temperatures -- not only was last month the hottest June ever recorded, it was the fourth consecutive month in which the standing high mark was topped, according to the US National Oceanic and Atmospheric Administration (NOAA).