Τίτλος:
Improved Representation of Clouds in the Atmospheric Component LMDZ6A of the IPSL-CM6A Earth System Model
Γλώσσες Τεκμηρίου:
Αγγλικά
Περίληψη:
The cloud parameterizations of the LMDZ6A climate model (the atmospheric component of the IPSL-CM6 Earth system model) are entirely described, and the global cloud distribution and cloud radiative effects are evaluated against the CALIPSO-CloudSat and CERES observations. The cloud parameterizations in recent versions of LMDZ favor an object-oriented approach for convection, with two distinct parameterizations for shallow and deep convection and a coupling between convection and cloud description through the specification of the subgrid-scale distribution of water. Compared to the previous version of the model (LMDZ5A), LMDZ6A better represents the low-level cloud distribution in the tropical belt, and low-level cloud reflectance and cover are closer to the PARASOL and CALIPSO-GOCCP observations. Mid-level clouds, which were mostly missing in LMDZ5A, are now better represented globally. The distribution of cloud liquid and ice in mixed-phase clouds is also in better agreement with the observations. Among identified deficiencies, low-level cloud covers are too high in mid-latitude to high-latitude regions, and high-level cloud covers are biased low globally. However, the cloud global distribution is significantly improved, and progress has been made in the tuning of the model, resulting in a radiative balance in close agreement with the CERES observations. Improved tuning also revealed structural biases in LMDZ6A, which are currently being addressed through a series of new physical and radiative parameterizations for the next version of LMDZ. ©2020. The Authors.
Συγγραφείς:
Madeleine, J.-B.
Hourdin, F.
Grandpeix, J.-Y.
Rio, C.
Dufresne, J.-L.
Vignon, E.
Boucher, O.
Konsta, D.
Cheruy, F.
Musat, I.
Idelkadi, A.
Fairhead, L.
Millour, E.
Lefebvre, M.-P.
Mellul, L.
Rochetin, N.
Lemonnier, F.
Touzé-Peiffer, L.
Bonazzola, M.
Περιοδικό:
Journal of Advances in Modeling Earth Systems
Εκδότης:
Wiley-Blackwell Publishing Ltd
Λέξεις-κλειδιά:
Earth (planet); Parameterization, Atmospheric components; Cloud parameterizations; Cloud radiative effects; Earth system model; Global distribution; High-latitude regions; Low-level cloud covers; Object oriented approach, Climate models, atmospheric convection; CALIPSO; climate modeling; cloud cover; cloud radiative forcing; CloudSat; observational method; PARASOL
DOI:
10.1029/2020MS002046
