TY - JOUR
T1 - Significant Increase in Sea Surface Temperature at the Genesis of Tropical Mesoscale Convective Systems
AU - Dong, Wenhao
AU - Zhao, Ming
AU - Ming, Yi
AU - Ramaswamy, V.
N1 - Funding Information:
The authors would like to thank Nathaniel C. Johnson and Hiroyuki Murakami for useful discussion and commenting on earlier versions of this paper. This research from the Geophysical Fluid Dynamics Laboratory is supported by NOAA's Science Collaboration Program and administered by UCAR's Cooperative Programs for the Advancement of Earth System Science (CPAESS) under awards NA16NWS4620043 and NA18NWS4620043B
Publisher Copyright:
© 2022. The Authors.
PY - 2022/12/28
Y1 - 2022/12/28
N2 - An event-based assessment of the sea surface temperature (SST) threshold at the genesis of tropical mesoscale convective systems (MCSs) is performed in this study. We show that this threshold (SSTG) has undergone a significant warming trend at a rate of ∼0.2°C per decade. The SSTG shows a remarkable correspondence with the tropical mean SST and upper-tropospheric temperature on interannual and longer timescales. Using a high-resolution global climate model that permits realistic simulations of tropical MCSs, we find that the observed features of SSTG are well simulated. Both observation and model simulations demonstrate that the upward tendency in SSTG primarily results from the environmental SST warming over MCS genesis regions rather than the changes in MCS genesis location. A continuous increase in SSTG is projected in a warming simulation, but the relationship between SSTG and upper-tropospheric temperature remains unchanged, suggesting that the tropical tropospheric temperature generally follows a moist-adiabatic adjustment.
AB - An event-based assessment of the sea surface temperature (SST) threshold at the genesis of tropical mesoscale convective systems (MCSs) is performed in this study. We show that this threshold (SSTG) has undergone a significant warming trend at a rate of ∼0.2°C per decade. The SSTG shows a remarkable correspondence with the tropical mean SST and upper-tropospheric temperature on interannual and longer timescales. Using a high-resolution global climate model that permits realistic simulations of tropical MCSs, we find that the observed features of SSTG are well simulated. Both observation and model simulations demonstrate that the upward tendency in SSTG primarily results from the environmental SST warming over MCS genesis regions rather than the changes in MCS genesis location. A continuous increase in SSTG is projected in a warming simulation, but the relationship between SSTG and upper-tropospheric temperature remains unchanged, suggesting that the tropical tropospheric temperature generally follows a moist-adiabatic adjustment.
KW - mesoscale convective system
KW - sea surface temperature
KW - upper-tropospheric temperature
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U2 - 10.1029/2022GL101950
DO - 10.1029/2022GL101950
M3 - Article
AN - SCOPUS:85145237242
SN - 0094-8276
VL - 49
JO - Geophysical Research Letters
JF - Geophysical Research Letters
IS - 24
M1 - e2022GL101950
ER -