New MAPP-funded research assesses how changes in the tropical belt affect climate variability

  • 21 October 2015
  • Number of views: 1872

Research has shown that the tropical belt has expanded over the past several decades, but little is known about its variability before 1980.

Changes in the tropical belt are associated with shifts in subtropical dry zones and precipitation patterns, which can impact ecosystems, water resources, agriculture, and society. New research funded by CPO’s Modeling, Analysis, Predictions, and Projections program resulted in a paper titled “Southward Shift of the Northern Tropical Belt from 1945 to 1980,” recently published in Nature Geoscience.

The study by Dr. Andreas Fischer et al. evaluated how the position and width of the tropical belt changed from 1945 to 1980. They found that the northern tropical belt moved south from 1945 to 1980, primarily due to cooling sea-surface temperatures north of the equator and warming south of the equator, while the northern Hadley cell shifted southward in summer and winter. This Hadley cell shift was associated with significant droughts during this time period, suggesting that changes in the tropical belt and Hadley cell can substantially impact climate variability.

To view the paper, go to: 




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