April was the hottest April on record, according to data released by NASA, making it the sixth month in a row to have temperatures more than one degree Celsius above the 1951- 1980 average. The April fi gures released by NASA continued the remarkably warm start to 2016, with each month among those over the most abnormally hot months in more than 130 years of global figures. The increases measured by experts around the world mean that within the last year, global temperatures had increased by 25 per cent of the total increase since the 1880s. Within the last 18 months, around one quarter of all coral colonies in the oceans had suff ered bleaching as a result of warmer water and increased acidification. In such circumstances, the corals expel the algae living in their tissues and turn white. While coral can recover from such events, it is often fatal.