Assessment of nonlinear effects of a deep subgrid lake with an atmospheric single‐column model

Article Article scientifique Article Assessment of nonlinear effects of a deep subgrid lake with an atmospheric single‐column model eng 2020 author Goyette Stéphane 0000-0001-5199-5974 647994 author Fonseca Cédric 859374 author Truscello Léonard 782553 10.1002/joc.6890 0899-8418 https://onlinelibrary.wiley.com/doi/10.1002/joc.6890 Some nonlinear aspects due to the coupling of a single column atmospheric model (SCM) with both a land-surface model (LSM) and a lake model has lately been published by Goyette in 2017. In this previous study, the surface type abruptly changed from land to an open water surface. This article further investigates the potential of this SCM to explore the nonlinear effects through the analysis of the impacts of fractional land and open water surfaces on the surface fluxes and variables, as well as on the atmospheric air temperature,specific humidity, and wind speed vertical profiles, with an application to deep Lake Geneva, Switzerland. It is shown that the coupling methodology depending on the surface type produced realistic and coherent results and indicated that the mean fluxes and other relevant quantities may not be simply averaged on the basis of the fractional area of the land and that of the openwater. If Lake Geneva relative surface area is prescribed to its observed value with respect to the model grid-mesh size, the remaining being land surface,results showed maximum seasonal mean differences of 7.5 and 5.4 W m−2for the latent and sensible heat flux in Autumn respectively, 1.6 deg C, 0.8 gkg−1 for the screen-level air temperature and specific humidity in Autumn respectively,and 0.6 ms−1for the anemometer-level windspeed in Winter with respect to the original land surface, owing to the different behaviour of the vertical turbulent transfer of heat, moisture and momentum but also to the different thermal and radiative characteristics of land and water surfaces. Lake-atmosphere interactions LakeMIP Nonlinear effects Sensitivity study Single-columnmodels Subgrid-scale lake Dewey 333.7-333.9 Dewey 500.2 18 Institut des sciences de l'environnement 0DB 35 Groupe de physique appliquée 135 false 803 Groupe Kasparian International Journal of Climatology 5c9260c2-f840-4069-9f34-9a0ae9fbc499 Article (Published version) Restricted joc.6890.pdf 15953664 application/pdf restrictedAccess Centres et instituts / Institut des sciences de l'environnement Faculté des sciences / Section de physique / Groupe de physique appliquée

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Assessment of nonlinear effects of a deep subgrid lake with an atmospheric single‐column model	International Journal of Climatology			2020	310	5

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