Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Agreement in late twentieth century Southern Hemisphere stratospheric temperature trends in observations and CCMVal-2, CMIP3 and CMIP5 models
AU - Young, Paul
AU - Butler, Amy
AU - Calvo, Natalia
AU - Haimberger, Leopold
AU - Kushner, Paul
AU - Marsh, Dan
AU - Randel, William
AU - Rosenlof, Karen
N1 - ©2013. American Geophysical Union. All Rights Reserved.
PY - 2013/1/27
Y1 - 2013/1/27
N2 - We present a comparison of temperature trends using different satellite and radiosonde observations and climate (GCM) and chemistry-climate model (CCM) output, focusing on the role of photochemical ozone depletion in the Antarctic lower stratosphere during the second half of the twentieth century. Ozone-induced stratospheric cooling peaks during November at an altitude of approximately 100 hPa in radiosonde observations, with 1969-1998 trends in the range -3.8 to -4.7 K / dec. This stratospheric cooling trend is more than 50% greater than the previously estimated value of -2.4 K / dec [Thompson and Solomon, 2002], which suggested that the CCMs were overestimating the stratospheric cooling, and that the less complex GCMs forced by prescribed ozone were matching observations better. Corresponding ensemble mean model trends are -3.8 K / dec for the CCMs, -3.5 K / dec for the CMIP5 GCMs, and -2.7 K / dec for the CMIP3 GCMs. Accounting for various sources of uncertainty – including sampling uncertainty, measurement error, model spread, and trend confidence intervals – observations, and CCM and GCM ensembles are consistent in this new analysis. This consistency does not apply to every individual that comprises the GCM and CCM ensembles, and some do not show significant ozone-induced cooling. Nonetheless, analysis of the joint ozone and temperature trends in the CCMs suggests that the modeled cooling/ozone-depletion relationship is within the range of observations. Overall, this study emphasizes the need to use a wide range of observations for model validation, as well as sufficient accounting of uncertainty in both models and measurements.
AB - We present a comparison of temperature trends using different satellite and radiosonde observations and climate (GCM) and chemistry-climate model (CCM) output, focusing on the role of photochemical ozone depletion in the Antarctic lower stratosphere during the second half of the twentieth century. Ozone-induced stratospheric cooling peaks during November at an altitude of approximately 100 hPa in radiosonde observations, with 1969-1998 trends in the range -3.8 to -4.7 K / dec. This stratospheric cooling trend is more than 50% greater than the previously estimated value of -2.4 K / dec [Thompson and Solomon, 2002], which suggested that the CCMs were overestimating the stratospheric cooling, and that the less complex GCMs forced by prescribed ozone were matching observations better. Corresponding ensemble mean model trends are -3.8 K / dec for the CCMs, -3.5 K / dec for the CMIP5 GCMs, and -2.7 K / dec for the CMIP3 GCMs. Accounting for various sources of uncertainty – including sampling uncertainty, measurement error, model spread, and trend confidence intervals – observations, and CCM and GCM ensembles are consistent in this new analysis. This consistency does not apply to every individual that comprises the GCM and CCM ensembles, and some do not show significant ozone-induced cooling. Nonetheless, analysis of the joint ozone and temperature trends in the CCMs suggests that the modeled cooling/ozone-depletion relationship is within the range of observations. Overall, this study emphasizes the need to use a wide range of observations for model validation, as well as sufficient accounting of uncertainty in both models and measurements.
KW - RICH-obs
KW - RICH-τ
KW - RAOBCORE
KW - IUK
KW - HadAT2
KW - MSU
KW - CCMVal
KW - IPCC
KW - CMIP
U2 - 10.1002/jgrd.50126
DO - 10.1002/jgrd.50126
M3 - Journal article
VL - 118
SP - 605
EP - 613
JO - Journal of Geophysical Research: Atmospheres
JF - Journal of Geophysical Research: Atmospheres
SN - 0747-7309
IS - 2
ER -