ENSO signal in continental temperature and precipitation records

Abstract

Warm events in the tropical Pacific Ocean, associated with one extreme of the Southern Oscillation (generally known as El Nino–Southern Oscillation or ENSO events) are now known to be of global significance in perturbing the general circulation of the atmosphere1–8. It is also apparent that episodes of enhanced cold-water upwelling ('cold events') have an impact on large-scale atmospheric circulation patterns9–11. Here we examine the effect of warm and cold events on short-term fluctuations of continental surface air temperature and precipitation throughout the Northern Hemisphere using a newly compiled set of high-quality temperature and precipitation data12–13. The data were in the form of gridded anomalies from a 1951–70 reference mean for temperature and a 1921–60 reference mean for precipitation13–14.