Climate variability research aided by moored current profiles

Climate variability research includes questions ranging from "Will this winter be unusually dry or wet?" to "Are recent warming trends due to man's influence?" Their investigation requires the continuous measurement of many parameters over long periods of time, because the relevant forcing mechanisms occur over months to decades. This article focuses on one of those parameters, ocean currents, because of their role in distributing heat and freshwater in the world ocean. Acoustic Doppler current profilers (ADCPs) are now commonly used to measure ocean currents, and a brief discussion of their history and unique applicability is presented before a detailed discussion of three "prototypical" current regimes: the equatorial Pacific, western boundary currents and the Arctic. For each regime, the importance of current measurements to climate variability research is presented, and the particular difficulties associated with deploying oceanographic moorings within them are explored.