The observed widespread warming of the atmosphere and ocean, together with ice mass loss, support the conclusion that it is extremely unlikely that global climate change of the past 50 years can be explained without external forcing, and very likely that it is not due to known natural causes alone. (rogerpielkejr.blogspot.ru)
On short time scales, as happened in 1998, widespread warm temperatures in the tropical Pacific in El Niño years can pump up the heat. (dotearth.blogs.nytimes.com)
The observed widespread warming of the atmosphere and ocean, together with ice mass loss, support the conclusion that it is extremely unlikely [< 5 % probability] that global climate change of the past 50 years can be explained without external forcing and very likely that it is not due to known natural causes alone. (mediamatters.org)