Research output: Contribution to journal › Article › peer-review
Multimodel assessment of the upper troposphere and lower stratosphere : Tropics and global trends. / Gettelman, A.; Hegglin, M. I.; Son, S. -W.; Kim, J.; Fujiwara, M.; Birner, T.; Kremser, S.; Rex, M.; Anel, J. A.; Akiyoshi, H.; Austin, J.; Bekki, S.; Braesike, P.; Bruehl, C.; Butchart, N.; Chipperfield, M.; Dameris, M.; Dhomse, S.; Garny, H.; Hardiman, S. C.; Joeckel, P.; Kinnison, D. E.; Lamarque, J. F.; Mancini, E.; Marchand, M.; Michou, M.; Morgenstern, O.; Pawson, S.; Pitari, G.; Plummer, D.; Pyle, J. A.; Rozanov, E.; Scinocca, J.; Shepherd, T. G.; Shibata, K.; Smale, D.; Teyssedre, H.; Tian, W.
In: JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, Vol. 115, No. D3, ARTN D00M08, 23.10.2010.Research output: Contribution to journal › Article › peer-review
}
TY - JOUR
T1 - Multimodel assessment of the upper troposphere and lower stratosphere
T2 - Tropics and global trends
AU - Gettelman, A.
AU - Hegglin, M. I.
AU - Son, S. -W.
AU - Kim, J.
AU - Fujiwara, M.
AU - Birner, T.
AU - Kremser, S.
AU - Rex, M.
AU - Anel, J. A.
AU - Akiyoshi, H.
AU - Austin, J.
AU - Bekki, S.
AU - Braesike, P.
AU - Bruehl, C.
AU - Butchart, N.
AU - Chipperfield, M.
AU - Dameris, M.
AU - Dhomse, S.
AU - Garny, H.
AU - Hardiman, S. C.
AU - Joeckel, P.
AU - Kinnison, D. E.
AU - Lamarque, J. F.
AU - Mancini, E.
AU - Marchand, M.
AU - Michou, M.
AU - Morgenstern, O.
AU - Pawson, S.
AU - Pitari, G.
AU - Plummer, D.
AU - Pyle, J. A.
AU - Rozanov, E.
AU - Scinocca, J.
AU - Shepherd, T. G.
AU - Shibata, K.
AU - Smale, D.
AU - Teyssedre, H.
AU - Tian, W.
PY - 2010/10/23
Y1 - 2010/10/23
N2 - The performance of 18 coupled Chemistry Climate Models (CCMs) in the Tropical Tropopause Layer (TTL) is evaluated using qualitative and quantitative diagnostics. Trends in tropopause quantities in the tropics and the extratropical Upper Troposphere and Lower Stratosphere (UTLS) are analyzed. A quantitative grading methodology for evaluating CCMs is extended to include variability and used to develop four different grades for tropical tropopause temperature and pressure, water vapor and ozone. Four of the 18 models and the multi-model mean meet quantitative and qualitative standards for reproducing key processes in the TTL. Several diagnostics are performed on a subset of the models analyzing the Tropopause Inversion Layer (TIL), Lagrangian cold point and TTL transit time. Historical decreases in tropical tropopause pressure and decreases in water vapor are simulated, lending confidence to future projections. The models simulate continued decreases in tropopause pressure in the 21st century, along with similar to 1K increases per century in cold point tropopause temperature and 0.5-1 ppmv per century increases in water vapor above the tropical tropopause. TTL water vapor increases below the cold point. In two models, these trends are associated with 35% increases in TTL cloud fraction. These changes indicate significant perturbations to TTL processes, specifically to deep convective heating and humidity transport. Ozone in the extratropical lowermost stratosphere has significant and hemispheric asymmetric trends. O-3 is projected to increase by nearly 30% due to ozone recovery in the Southern Hemisphere (SH) and due to enhancements in the stratospheric circulation. These UTLS ozone trends may have significant effects in the TTL and the troposphere.
AB - The performance of 18 coupled Chemistry Climate Models (CCMs) in the Tropical Tropopause Layer (TTL) is evaluated using qualitative and quantitative diagnostics. Trends in tropopause quantities in the tropics and the extratropical Upper Troposphere and Lower Stratosphere (UTLS) are analyzed. A quantitative grading methodology for evaluating CCMs is extended to include variability and used to develop four different grades for tropical tropopause temperature and pressure, water vapor and ozone. Four of the 18 models and the multi-model mean meet quantitative and qualitative standards for reproducing key processes in the TTL. Several diagnostics are performed on a subset of the models analyzing the Tropopause Inversion Layer (TIL), Lagrangian cold point and TTL transit time. Historical decreases in tropical tropopause pressure and decreases in water vapor are simulated, lending confidence to future projections. The models simulate continued decreases in tropopause pressure in the 21st century, along with similar to 1K increases per century in cold point tropopause temperature and 0.5-1 ppmv per century increases in water vapor above the tropical tropopause. TTL water vapor increases below the cold point. In two models, these trends are associated with 35% increases in TTL cloud fraction. These changes indicate significant perturbations to TTL processes, specifically to deep convective heating and humidity transport. Ozone in the extratropical lowermost stratosphere has significant and hemispheric asymmetric trends. O-3 is projected to increase by nearly 30% due to ozone recovery in the Southern Hemisphere (SH) and due to enhancements in the stratospheric circulation. These UTLS ozone trends may have significant effects in the TTL and the troposphere.
KW - CHEMISTRY-CLIMATE MODEL
KW - GENERAL-CIRCULATION MODEL
KW - TECHNICAL NOTE
KW - TROPOPAUSE TEMPERATURES
KW - ATMOSPHERIC CHEMISTRY
KW - OZONE
KW - TRANSPORT
KW - SIMULATIONS
KW - AEROSOLS
KW - SURFACE
U2 - 10.1029/2009JD013638
DO - 10.1029/2009JD013638
M3 - статья
VL - 115
JO - Journal of Geophysical Research D: Atmospheres
JF - Journal of Geophysical Research D: Atmospheres
SN - 2169-897X
IS - D3
M1 - ARTN D00M08
ER -
ID: 117040986