Last updated October 10, 2018

Role of sea surface temperature and soil-moisture feedback in the 1998 Oklahoma–Texas drought

  • States that the drought that affected the US states of Oklahoma and Texas in the summer of 1998 was strong and persistent, with soil moisture reaching levels comparable to those of the 1930s ‘dust bowl’
  • Presents results from mechanistic experiments to clarify the origin and maintenance of this extratropical climate extreme
  • Uses global atmospheric models and a regional model to isolate regional climate feedbacks
  • Concludes that during April and May 1998, sea surface temperature anomalies combined with a favourable atmospheric circulation to establish the drought
  • Finds that in June–August, the regional positive feedback associated with lower evaporation and precipitation contributed substantially to the maintenance of the drought
  • States that the drought ended in the autumn, when stronger large-scale weather systems were able to penetrate the region and overwhelm the soil-moisture feedback