Pacific Ocean one branch flows around Cape Horn and the other turns north to form the Peru or Humboldt Current. The climate patterns of the Northern and Southern Hemispheres generally mirror each other. The trade winds in the southern and eastern Pacific are remarkably steady while conditions in the North Pacific are far more varied with, for example, cold winter temperatures on the east coast of Russia contrasting with the milder weather off British Columbia during the winter months due to the preferred flow of ocean currents. In the tropical and subtropical Pacific, the El Niño Southern Oscillation (ENSO) affects weather conditions.
Environmental threats to the Great Barrier Reef consequential rise of sea temperatures, gradual ocean acidification and an increase in the number of "intense weather events". Hughes writes of "the demonstrable failure of the state and Commonwealth" to address the issue of climate change in his August 2014 article. Furthermore, a temperature rise of between two and three degrees Celsius would result in 97% of the Great Barrier Reef being bleached every year. Reef scientist Terry Done has predicted that a one-degree rise in global temperature would result in 82% of the reef bleached—two degrees would result in 97%, while three degrees would result in "total devastation". A