Measurements of the isotopic composition of stratospheric water by the ATMOS instrument are used to infer the convective history of stratospheric air. The average water vapor entering the stratosphere is found to be highly depleted of deuterium, with 6Dw of670 + 80 (67% deuterium loss). Model calculations predict, however, that under conditions of thermodynamic equilibrium, dehydration to strat...

Air may cross the tropical tropopause either by gradual ascent or in localized episodes associated with convection. While observations demonstrate that water vapor mixing ratios of air entering the tropical stratosphere are consistent with the mean tropical tropopause temperature, they do not resolve key mechanistic questions, such as the relative contribution of gradual or episodic transport, ...

This study presents an empirical relation that links the volume extinction coefficients of water clouds, the layer integrated depolarization ratios measured by lidar, and the effective radii of water clouds derived from collocated passive sensor observations. Based on Monte Carlo simulations of CALIPSO lidar observations, this method combines the cloud effective radius reported by MODIS with th...

The Deepwater Horizon blowout resulted in the release of millions of barrels of crude oil. As part of the Trustees' Natural Resource Damage Assessment, a testing program was implemented to evaluate the toxicity of Deepwater Horizon oil and oil/dispersant mixtures to aquatic organisms from the Gulf of Mexico. Because of the variety of exposures that likely occurred, the program included 4 Deepwa...

Aerosol and water vapour measurements were performed with the lidar system WALES of Deutsches Zentrum für Luftund Raumfahrt (DLR) in October and November 2010 during the first mission with the new German research aircraft G55-HALO. Curtains composed of lidar profiles beneath the aircraft show the vertical and horizontal distribution and variability of water vapour mixing ratio and backscatter r...

abstract the limitation of water sources in most places all over the world, especially in arid and semi-arid lands is an important issue for those who live in these areas. many governments have dedicated their efforts toward finding new water resources to obtain water. fog and cap clouds harvesting are one of the candidate methods to produce pure water. many countries including chile, peru, ecu...

The objective of this study is to investigate the quality of clouds simulated by the National Centers for Environmental Prediction global forecast system (GFS) model and to examine the causes for some systematic errors seen in the simulations through use of satellite and ground-based measurements. In general, clouds simulated by the GFS model had similar spatial patterns and seasonal trends as ...

We have successfully implemented an explicit cloud scheme within the Florida State University Global Spectral Model. This includes the liquid water mixing ratio and cloud fractions as two additional dependant variables. The main purpose of this extension is two fold: we wished to improve our global cloud forecasting capability (low, medium and high clouds) and to have a better definition of the...

We develop a series of models of transport in the upper tropical troposphere in order to explain the observed abundance and isotopic composition of stratospheric water vapor. We start with the Rayleigh fractionation process and add the effects of mixing and recirculation of stratospheric air through the upper troposphere. We compare our measurements with model calculations for a range of input ...