A formulation for boundary-layer cloud cover Export

@article{ekAG1991, abstract = {This study investigates the direct radiative effects of aerosols on the evolution of 32 atmospheric boundary layer (ABL), over a tropical site Anand for four days 33 representative to each season using land surface processes experiment (LASPEX) 34 datasets used in a one-dimensional ABL and radiative-transfer models. Simulations with 35 ABL model incorporating fixed aerosol loading with three different levels of absorption 36 and its perturbation with aerosol-free conditions were analyzed. The reduction in net 37 available flux (ΔNAF) increases with increase in aerosol absorption, resulting maximum 38 reduction for strongly absorbing type. In dry seasons, soil being dry, ΔNAF is 39 compensated almost equally by latent (LE) and sensible (H) heat fluxes. In wet season, 40 since soil moisture is abundant, LE dominates about 75\% in compensating ΔNAF. The 41 larger the absorption, the lesser the gradient between the surface and 2-meter air 42 temperature and hence more stable the surface layer. The reduction in vertical 43 temperature gradient ranges from 1.74º K (dry season) to 0.6º K (wet season). This 44 stabilization of the surface layer reduces the sensible heat flux and the surface 45 evaporation. Aerosol absorption decreases the turbulent heating but simultaneously 46 increases the solar heating, and in turn increases the air temperature. This affects the 47 inversion layer and hence the ABL height. It is found that absorbing aerosols delay the 48 growth and promote the early collapse of the ABL in all seasons.}, author = {Ek, M. and Mahrt, L.}, citeulike-article-id = {1456545}, citeulike-linkout-0 = {http://cat.inist.fr/?aModele=afficheN&cpsidt=5019508}, journal = {Annales Geophysicae}, keywords = {abl, cloud}, pages = {716--724}, posted-at = {2007-07-14 16:10:08}, priority = {2}, title = {A formulation for boundary-layer cloud cover}, url = {http://cat.inist.fr/?aModele=afficheN&cpsidt=5019508}, volume = {9}, year = {1991} }

TY - JOUR ID - ekAG1991 L3 - citeulike-article-id:1456545 N2 - This study investigates the direct radiative effects of aerosols on the evolution of 32 atmospheric boundary layer (ABL), over a tropical site Anand for four days 33 representative to each season using land surface processes experiment (LASPEX) 34 datasets used in a one-dimensional ABL and radiative-transfer models. Simulations with 35 ABL model incorporating fixed aerosol loading with three different levels of absorption 36 and its perturbation with aerosol-free conditions were analyzed. The reduction in net 37 available flux (ΔNAF) increases with increase in aerosol absorption, resulting maximum 38 reduction for strongly absorbing type. In dry seasons, soil being dry, ΔNAF is 39 compensated almost equally by latent (LE) and sensible (H) heat fluxes. In wet season, 40 since soil moisture is abundant, LE dominates about 75% in compensating ΔNAF. The 41 larger the absorption, the lesser the gradient between the surface and 2-meter air 42 temperature and hence more stable the surface layer. The reduction in vertical 43 temperature gradient ranges from 1.74º K (dry season) to 0.6º K (wet season). This 44 stabilization of the surface layer reduces the sensible heat flux and the surface 45 evaporation. Aerosol absorption decreases the turbulent heating but simultaneously 46 increases the solar heating, and in turn increases the air temperature. This affects the 47 inversion layer and hence the ABL height. It is found that absorbing aerosols delay the 48 growth and promote the early collapse of the ABL in all seasons. JF - Annales Geophysicae EP - 724 TI - A formulation for boundary-layer cloud cover VL - 9 SP - 716 KW - abl KW - cloud AU - Ek, M AU - Mahrt, L PY - 1991/// UR - http://cat.inist.fr/?aModele=afficheN&cpsidt=5019508 ER -