Sep 10, 2013

Temperature trends in the tropical upper troposphere and lower stratosphere: Connections with sea surface temperatures and implications for water vapor and ozone

Garfinkel, C. I., Waugh, D. W., Oman, L. D., Wang, L., Hurwitz, M. M.
Journal of Geophysical Research: Atmospheres
  • Analyzes the zonal structure of tropical lower stratospheric temperature, water vapor, and ozone trends
  • States warming in the tropical upper troposphere over the past 30 years is strongest near the Indo-Pacific warm pool, while the warming trend in the western and central Pacific is much weaker; states that in the lower stratosphere, these trends are reversed: the historical cooling trend is strongest over the Indo-Pacific warm pool and is weakest in the western and central Pacific
  • Uses targeted experiments with a chemistry-climate model to demonstrate that sea surface temperature (hereafter SST) trends are driving the zonal asymmetry in upper tropospheric and lower stratospheric tropical temperature trends
  • States warming SSTs in the Indian Ocean and in the warm pool region have led to enhanced moist heating in the upper troposphere
  • Finds water vapor trends at the tropopause can be explained by trends in saturation water vapor
  • States the anomalous circulation has led to zonal structure in the ozone and water vapor trends near the tropopause, and subsequently to less water vapor entering the stratosphere