In recent years climate change has impacted the Great Barrier Reef. Climate change has resulted in a increase in temperature. The increase of temperature means that during the summer months the coral goes into "thermal stress". thermal stress makes the zooxanthellae (the organism that give the coral its colour) splits with the coral and takes the colour away from the coral.This makes the coral turn into a white colour. People refer to this as coral bleaching. Within the period of 1998-2002 the number of bleached coral had increased by 10%.