Multiyear La Niña Events and Persistent Drought in the Contiguous United States
|Multiyear La Niña Events and Persistent Drought in the Contiguous United States
|Year of Publication
|Cole, J, Overpeck, JT, Cook, E
|Geophysical Research Letters
|1812 Drought, 3344 Meteorology and Atmospheric Dynamics: Paleoclimatology, 4215 Climate and interannual variability, 4522 Oceanography: Physical: El Niño
La Niña events typically bring dry conditions to the southwestern United States. Recent La Niñas rarely exceed 2 years duration, but a new record of ENSO from a central Pacific coral reveals much longer La Niña anomalies in the 1800s. A La Niña event between 1855–63 coincides with prolonged drought across the western U.S. The spatial pattern of this drought correlates with that expected from La Niña during most of the La Niña event; land-surface feedbacks are implied by drought persistence and expansion. Earlier periods also show persistent La Niña-like drought patterns, further implicating Pacific anomalies and surface feedbacks in driving prolonged drought. An extended index of the Pacific Decadal Oscillation suggests that extratropical influences would have reinforced drought in the 1860s and 1890s but weakened it during the La Niña of the 1880s.