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Abstract While many modeling studies have attempted to estimate how tropical cyclone (TC) precipitation is impacted by climate change, the multitude of analysis techniques and methodologies have resulted in varying conclusions. Simplified models may be able to help overcome this problem. Radiative‐convective equilibrium (RCE) model simulations have been used in various configurations to study fundamental aspects of Earth's climate. While many RCE modeling studies have focused on TC genesis, intensification, and size, limited work has been done using RCE to study TC precipitation. In this study, the response of TC precipitation to sea surface temperature (SST) change is analyzed in global Community Atmosphere Model (CAM) aquaplanet simulations run with Radiative‐Convective Equilibrium Model Intercomparison Project protocols, with the addition of planetary rotation. We expect that the insight gained about how TC precipitation responds to SST warming will help predict how TCs in the real world respond to climate change. In the CAM RCE simulations, the warmer SST simulations have less TCs on average, but the TCs tend to be larger in outer size and more intense. As simulation SST increases, more extreme precipitation rates occur within TCs, and more of the TC precipitation comes from these extreme rates. For extreme (99th percentile) TC precipitation, SST, and TC intensity increases dominate the 8.6% per K increase, while TC outer size changes have little impact. For accumulated TC precipitation, SST, and TC intensity contributions are still the majority, but TC outer size changes also contribute to the 6.6% per K increase.
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The Feedback of Cold Wakes on Tropical Cyclones
Abstract Tropical cyclones (TCs) cause negative sea surface temperature anomalies by vertical mixing and other processes. Such cold wakes can cover substantial areas and persist for a month or longer. It has long been hypothesized that cold wakes left behind by intense TCs reduce the likelihood of subsequent TC development. Here, we combine satellite observations, a global atmospheric model, and a high‐resolution TC downscaling model to test this hypothesis and examine the feedback of cold wakes on subsequent TC tracks and intensities. Overall, cold wakes reduce the frequency of weak to moderate events but increase the incidence of very intense events. There is large spatial heterogeneity in the TC response, such as a southward shift of track density in response to cold wakes similar to that generated by Florence (2018). Cold wakes may be important for modeling and forecasting TCs, interpreting historical records and understanding feedbacks in a changing climate.
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- Award ID(s):
- 1854956
- PAR ID:
- 10368950
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 48
- Issue:
- 7
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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