Clouds, Precipitation and Marine Boundary Layer Structure During MAGIC

Download or read book Clouds, Precipitation and Marine Boundary Layer Structure During MAGIC written by Xiaoli Zhou and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "The recent ship-based MAGIC field campaign with the marine-capable Second ARM Mobile Facility (AMF2) deployed on the Horizon Lines cargo container M/V Spirit provided one-year inter-seasonal high-resolution observations of clouds and precipitation between Los Angeles, California, and Honolulu, Hawaii. As expected, marine boundary layer (MBL) clouds have a much higher frequency of occurrence than other cloud types. The MBL clouds demonstrate propensity to produce precipitation, which often evaporates before reaching the ground. MBL clouds occur more often in the warm season than in the cold season, reflecting the importance of large-scale subsidence. A clear bimodal structure of the probability distribution of MBL cloud occurrence is observed during MAGIC, with over 40% of the legs showing low cloud cover near Honolulu and more than 70% of the legs displayed full coverage MBL clouds near California. Inversion and transition layers within the MBL are quantitatively defined, and the observed increasing and weakening inversion near Hawaii is consistent with the increase in the heights of the MBL cloud tops and the decrease in the MBL cloud fraction (CF). Stratocumuli generally form just below the inversion layer while cumuli are concentrated just above or inside the transition layer. The impacts of the estimated inversion strength (EIS) and the sea surface temperature (SST) on CF are also examined. EIS might be a good predictor of average MBL cloud amount under a wide range of climatological conditions, but it is insufficient to separate stratocumulus from cumulus on an individual basis. MBL cloud fraction exhibits a nonlinear relationship with SST, here parameterized as a quadratic, but the scatter of the data indicates that other parameters also affect this quantity." --