Influence of El Nio-Southern Oscillation on the middle atmosphere temperature and ozone
【摘要】：Using 9.5 years of middle atmosphere temperature and ozone datasets between January 2002 and June 2011 observed by Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) onboard NASA’s Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) and 27 years of Whole Atmospheric Community Climate Model (WACCM) version 3.0 datasets between 1979 and 2006, we study the influence of El Nio-Southern Oscillation (ENSO) on the middle atmosphere temperature and ozone. The significant temperature response is observed to be negative (~1K/MEI) in the tropical upper stratosphere, while positive (1-1.5K/MEI) in the Northern Hemisphere middle latitude. This anti-correlation feature is also well simulated by WACCM, but with only half as strong as that observed by SABER. The ozone response in the upper stratosphere is just out of phase with temperature response as revealed by both SABER and WACCM results, suggesting the enhanced upwelling in the tropical upper stratosphere and downwelling in the Northern Hemisphere middle latitudes during El Ni?o event. This is different from in-phase feature of the temperature and ozone responses to ENSO in the lower stratosphere. Both SABER and WACCM also suggests a significant positive temperature response to ENSO (~1K/MEI) in the tropical middle mesosphere and negative (~-1.0K/MEI) in the Northern middle latitude. The mesospheric temperature response is out of phase with the stratospheric signal, suggesting the enhanced downwelling in the tropical middle mesosphere and upwelling in the Northern Hemisphere middle latitudes during El Nio event.