Direct estimation of the global distribution of vertical velocity within cirrus clouds.

ABSTRACT: Cirrus clouds determine the radiative balance of the upper troposphere and the transport of water vapor across the tropopause. The representation of vertical wind velocity, W, in atmospheric models constitutes the largest source of uncertainty in the calculation of the cirrus formation rate. Using global atmospheric simulations with a spatial resolution of 7 km we obtain for the first time a direct estimate of the distribution of W at the scale relevant for cirrus formation, validated against long-term observations at two different ground sites. The standard deviation in W, σ _w , varies widely over the globe with the highest values resulting from orographic uplift and convection, and the lowest occurring in the Arctic. Globally about 90% of the simulated σ _w values ar

SUBMITTER: Barahona D 

PROVIDER: S-EPMC5533806 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature