Abstract Cirrus dominate the longwave radiative budget of the tropics. For the first time, the variability in cirrus properties and longwave cloud radiative effects (CREs) that arises from using different microphysical schemes within nudged global storm‐resolving simulations from a single model, is quantified. Nudging allows us to compute radiative biases precisely using coincident satellite measurements and to fix the large‐scale dynamics across our set of simulations to isolate the influence of microphysics. We run 5‐day simulations with four commonly‐used microphysics schemes of varying complexity (SAM1MOM, Thompson, M2005 and P3) and find that the tropical average longwave CRE varies over 20 W m−2between schemes. P3 best reproduces observed longwave CRE. M2005 and P3 simulate cirrus with realistic frozen water path but unrealistically high ice crystal number concentrations which commonly hit limiters and lack the variability and dependence on frozen water content seen in aircraft observations. Thompson and SAM1MOM have too little cirrus.
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Sensitivity of Deep Convection and Cross‐Tropopause Water Transport to Microphysical Parameterizations in WRF
Key Points Significant sensitivity of mid‐latitude deep convective storm and the associated anvil cirrus cloud to choice of model microphysics schemes Hydrometeor size‐dependent microphysical process are linked with large variability in storm dynamics Six bulk microphysics schemes produced an order of magnitude spread in above‐tropopause water vapor concentrations
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- Award ID(s):
- 1743753
- PAR ID:
- 10466375
- Date Published:
- Journal Name:
- Journal of Geophysical Research: Atmospheres
- Volume:
- 128
- Issue:
- 14
- ISSN:
- 2169-897X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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