Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 16 of 16 for “"cloud fraction"”.
-
Evaluating and Correcting the Effect of Sensor Spatial Resolution on Cloud Fraction Derived from Satellite Instruments
This study examines the biases in cloud fraction (CF) derived from satellite instruments that are due to the effect of sensor spatial resolution. In total, 1405 15 m resolution ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) scenes over cumulus-dominated regions including the …
-
An Investigation of the Relationship Between Low Cloud Cover And Lower Tropospheric Stability Using MISR
Marine boundary layer clouds account for a significant amount of uncertainty in future climate change projections from general circulation models (GCMs). To reduce the uncertainty of the role of clouds in GCMs, improved cloud parameterizations and evaluations of these parameterizations are often …
-
Cloud Observations From Eos-Terra: From Conception to Interpretation of Cloud Climatologies With a Focus on Small Clouds
Global comparison between the MISR and MODIS cloud masks shows large discrepancies over regions dominated by small clouds. This discrepancy was further explored using an ASTER dataset at 15m resolution over the tropical western Atlantic. On average, MODIS and MISR overestimate cloud fraction by 18% …
-
Satellite Cloud Detection With Shortwave Channels: Algorithms, MISR Applications, and Three-Dimensional Radiative Effects
… fundamental step in satellite remote sensing---cloud detection, which has been known as the largest source of error in the retrievals of satellite geophysical products. This thesis consists of two parts: the operational part and the theoretical part. Specifically, the operational part is on the …
-
The representation of cloud cover in atmospheric general circulation models
… of improvements made in the representation of clouds in the global forecast model of the European Centre of Medium-Range Weather Fore- casts (ECMWF). Cloud parametrization has long been identified as one of the most crucial and uncertain aspects in General Circulation Models (GCMs) of the …
-
On the role of warm rain clouds in the tropics
… algorithm has been developed for warm rain clouds using Tropical Rainfall Measuring Mission (TRMM) satellite measurements. The algorithm uses TRMM Microwave Imager (TMI) brightness temperatures that have been deconvolved to the 19-GHz field-of-view (FOV) to retrieve cloud liquid water path …
-
Dependence of tropical cirrus clouds on sea surface temperature and consequences for the Archean climate
… observationally the variation of upper level cloud fraction with sea surface temperature in tropical oceanic regions. We also explore the consequences of a cloud feedback, arising from variations in the coverage of thin upper level clouds, in the climate of the Archean using a simple …
-
A Predictor Analysis Framework for Surface Radiation Budget Reprocessing Using Design of Experiments
… The interaction of Cosine Solar Zenith Angle and Cloud Fraction had the strongest influence on the output data in the Amazon, Sahara Desert and Mt. Everest Regions, while the interaction of Cloud Fraction and Cloudy Shortwave Radiance most significantly affected output data in the Indian Ocean …
-
Comparison Of Ceres-Modis Derived Polar Cloud Properties With Cloudsat/calipso And Ground-Based Measurements
… satellites often face difficulty when detecting clouds over snow and ice covered surfaces beneath them. The recent launches of active satellites, which directly measure cloud properties, have allowed scientists to gain a firsthand look at the complex cloud profiles across polar regions. To help …
-
Linearity of the Climate System Response to Antarctic Topography Change
… the warming is associated with an increase in cloud fraction at all levels and downwelling longwave radiation over the Southern Ocean. Finally, experiments were conducted with a fully-coupled global climate model using Antarctic ice sheet topography from a West Antarctic Ice Sheet (WAIS) …
-
Multiscale Study of the Interactions between Climate, Land Use, and Agricultural Productivity in Western Sahel: A Case Study of Chad
… and negatively correlated with the temperature. Cloud fraction amounts, specific humidity, aerosol optical depth, soil moisture, and NDVI values are higher in wetter years than in dryer years; in contrary, wind speeds and surface air temperature are lower during wetter years. The land use land …
-
A Study on the Diurnal and Seasonal Cycles of Tropical Cirrus Clouds
Tropical cirrus clouds (TCC) regulate the Earth’s radiative energy budget. However, mechanisms of the diurnal and seasonal cycles of their occurrence still require further investigation due to limited observations. This study utilizes observational data from the Cloud-Aerosol Transport System …
-
Examining the Influence of Aerosols from Air Pollution on Current and Projected Temperatures in the Urban Area of Chongqing, China
… while the other incorporates the aerosol-cloud-radiation effect. A combination of in-situ observations, remote sensing data, regional climate model and global climate model outputs were used to study past, current, and future urban climate as a function of changes in aerosol …
-
Optimal locations for the ground segment of optical space communications networks
… for the laser beam to penetrate atmospheric clouds. Geographic diversity of ground stations has been proposed as an alternative to mitigate these effects. This thesis uses the systems architecture approach to analyze different architectures for the ground segment of an optical space …
-
Arctic Cloud, Radiation and their Interactions with Sea Ice
… coverage and thickness at impressive rates. The cloud-radiation feedback is believed to be one of the critical reasons for Arctic sea ice long-term trends and variability. Therefore, this study aims to investigate the role of cloud-radiation feedback in modulating Arctic sea ice changes from …
-
Modelling Climate Changes, Biogenic Emissions and Tropospheric Chemistry in Southeast Asia.
… increase of surface temperature and decreased cloud fraction in both seasons in the A2 and B2 scenarios. Future changes in other climatic variables, such as precipitation and boundary layer, have shown a high degree of variability. The combined effect of atmospheric forcing and landcover …