Judah Cohen, Karl Pfeiffer , Jennifer Francis

Oceanography

Published date January 23, 2017

Winter 2015/16: A Turning Point in ENSO-Based Seasonal Forecasts

  • States that the ocean-atmosphere coupled mode known as the El Niño-Southern Oscillation is considered the dominant mode of global climate variability and is the cornerstone of operational seasonal climate forecasts issued worldwide
  • States that winter 2015/16 forecasts are not noteworthy for their success but rather for their flaws. The inability of the global climate models to predict large-scale climate anomalies likely results from the models’ over-sensitivity to tropical forcing
  • Argues that Arctic influences were also important in causing the observed weather patterns of winter 2015/16, in particular, diminished Arctic sea ice cover, extreme warm Arctic temperatures, and extensive Siberian snow cover
  • Finds the weak response of the models to Arctic forcing contributed to seasonal forecast errors
  • Recommends complementing the influence of the tropical ocean with contributions from Arctic factors to improve seasonal climate forecasts