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Images: New Weather-Shifting Climate Cycle Revealed

WHOI scientist Kris Karnauskas and colleagues have found evidence for a natural 100-year cycle that shifts Pacific Ocean temperatures and rearranges rainfall and weather patterns around the globe. (Tom Kleindinst, Woods Hole Oceanographic Institution)

Red and blue (cooler) colors indicate warmer- and cooler-than-normal temperatures surface ocean temperatures during what scientists call the positive phase of the Pacific Centennial Oscillation (PCO). Changes of even a fraction of a degree Celsius can strongly influence rainfall and storm patterns throughout the Pacific region and beyond. The negative phase of the PCO is below. (Kris Karnauskas, Woods Hole Oceanographic Institution)

Pacific Ocean surface temperatures—and global rainfall pattern—reverse in the negative phase of the Pacific Centennial Oscillation. (Kris Karnauskas, Woods Hole Oceanographic Institution)

Red indicates where more rainfalls, and blue indicates where less rain falls during the positive phase of the predicted Pacific Centennial Oscillation (PCO). Rainfall patterns shift when the PCO seesaws into its negative phase. (Kris Karnauskas, Woods Hole Oceanographic Institution)

The El Niño-Southern Oscillation is a natural cycle that recurs over two to seven years. When surface temperatures in the eastern equatorial Pacific are warmer than usual (an El Niño event), heavy rains hit East Africa and droughts beset India, Indonesia, and Australia. When ocean conditions flip-flop (a La Niña), so do global rainfall patterns. (Fern Gibbons, Woods Hole Oceanographic Institution)