Realistic assessment of the vertical distribution of clouds, particularly the occurrence
of multi-layered systems, is critical for accurate calculations of radiative transfer in
general circulation models. Such information is also useful in the design and improvement
of satellite retrieval techniques. Current methods for retrieving cloud properties
from satellite data assume...
1-km MODIS observations of ship tracks off the west coast of the U.S. are used to characterize changes in cloud visible optical depths, cloud droplet radii, cloud cover fraction, and column cloud liquid water amount as low-level marine clouds respond to particle pollution from underlying ships. This study re-examines the...
A multispectral retrieval method is developed on the 100 km regional scale to extract
the temperature, particle size, fractional cover and 11-μm emissivity of clouds which
may be semitransparent in the infrared based on emitted radiances. The scheme utilizes
the nonlinear relationship between emitted radiances when clouds are semitransparent and...
The atmospheric radiative transfer model MOCARAT was developed and is
presented in this thesis. MOCARAT employs a Monte Carlo Technique for the
accurate modeling of band radiances and reflectances in an atmospheric system
with a ruffled ocean surface as a lower boundary. The atmospheric radiative
transfer is modeled with consideration...
One method of estimating the longwave radiative heating of the atmosphere is to
combine satellite observations of emitted radiances with those computed from synoptic
temperature and humidity profiles. Modeled and observed radiances are brought into
agreement by altering cloud properties or even by adjusting the temperature and water
Cloud reflectivity is a function of cloud liquid water content and droplet
number concentration. Since cloud droplets form around pre-existing aerosol
particles, cloud droplet number concentration depends on the availability of
particles that can serve as cloud condensation nuclei. Given constant liquid
water amount, increased availability of cloud condensation nuclei...
The accurate determination of cloud cover amount is important for characterizing
the role of cloud feedbacks in the climate system. Clouds have a large influence on
the climate system through their effect on the earth's radiation budget. As indicated
by the NASA Earth Radiation Budget Experiment (ERBE), the change in...
One kilometer Moderate Resolution Imaging Spectroradiometer (MODIS) observations for Terra (morning) and Aqua (afternoon) satellites were used to follow the morning to afternoon evolution of marine stratocumulus clouds that were affected by ship stack exhaust. The observations covered the summer months of 2002-2003 and August 2007 for marine layers off...
Adiabatic parcel models suggest specific relationships between cloud thickness and cloud properties. Such relationships govern cloud radiative forcing and thus cloud feedbacks in the climate system. Current remote sensing techniques work well at measuring these properties in low-level cloud systems that are overcast. Significant biases exist, however, when measuring cloud...
The Earth Radiation Budget Experiment (ERBE) uses Angular Dependence Models
(ADMs) to convert satellite observed radiances to radiative fluxes at the top of the
atmosphere. Owing to errors in scene identification and to the relationship between
the spatial scales of cloud systems and the spatial resolution of the ERBE scanner,...