El Niño Southern Oscillation (ENSO) is a large-scale ocean-atmosphere interaction in the tropical Pacific Ocean. ENSO consists of oscillations between a warm phase (El Niño) and a cool phase (La Niña).
It has fallen upon climate scientists to develop the technical sophistication and to employ the research methods necessary to understand climate variables, how they change across time and space, and the degree of human-caused climate disruption.
U.S. temperature extremes in 2014 have been exceptional—with record heat in the West and cooler than average temperatures in the East—and many scientists think climate change may be contributing. Temperature extremes occur when regions experience temperatures at the top or bottom 10% of the historical range of recorded values.