El Nino unusually active in the late 20th century

Reliable prediction of El Nino response to global warming is difficult, as El Nino varies naturally over decades and centuries. Instrumental records are too short to determine whether recent changes are natural or attributable to increased greenhouse gases. An international team of scientists now show that recent El Nino activity is the highest for the past 700 years, possibly a response to global warming. The work is published in the June 30, 2013, online issue of Nature Climate Change.

Fuente : http://www.eurekalert.org/pub_releases/2013-06/uoh…