El Niño in 2015-16: The View from Kiritimati Island

Kiritimati (pronounced "Christmas") Island, located at (2.0°N, 157.4°E), is one of the Line Islands in the eastern portion of the Republic of Kiribati ("KEER-eh-bahss").  The world's largest coral atoll in terms of land area was uninhabited when Europeans first encountered it, but is now home to about 6500 residents as well as visiting tourists and scientists.  The population is limited by several factors including its remote location and the supply of freshwater, which comes directly from rainfall and from groundwater in the form of freshwater lenses below the land's surface.  Kiritimati's long-term mean annual rainfall is about 1000 mm with a standard deviation of about 750mm.  During 10 weeks in January through March 2016, instruments deployed as part of NOAA's El Niño Rapid Response (ENRR) Field Campaign measured almost 940mm of rain, more than half of which fell in 4 separate events lasting less than 48 hours each.  Here we discuss the very different weather El Niño brings to Kiritimati Island.  We focus on a few particular high-impact events that occurred during ENRR; the associated forecasting challenges faced by the Kiribati Meteorological Service; and the short- and long-term effects the copious rains of 2015-2016 had on Kiritimati Island and its people.