Convective Elements in the Marine Atmospheric Boundary Layer. Part I: Conditional Sampling Statistics

Abstract The properties of updrafts and downdrafts through the entire depth of the marine atmospheric boundary layer are investigated using conditional sampling based on an indicator function derived from the vertical velocity time series. Statistics on event size, number density and area occupied are obtained, along with conditional averages of the meteorological variables and percent contributions to the fluxes by updrafts, downdrafts and the environment. A single profile is obtained for convective mass flux based on conditional averaging of updrafts and downdrafts applicable to the fluxes of latent and sensible heat and momentum.