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 20 of 23 for “"quikscat"”.
-
High Resolution Wind Retrieval for SeaWinds on QuikSCAT
<p>An algorithm has been developed that enables improved the resolution wind estimates from SeaWinds data. This thesis presents the development of three key portions of the high resolution wind retrieval algorithm: Compositing individual σ-0 measurements and Kp, Retrieved wind bias correction, and …
-
Oceanic Rain Identification Using Multifractal Analysis Of Quikscat Sigma-0
The presence of rain over oceans interferes with the measurement of sea surface wind speed and direction from the Sea Winds scatterometer and as a result wind measurements contain biases in rain regions. In past research at the Central Florida Remote Sensing Lab, it has been observed that rain has …
-
An Implementation of Field-Wise Wind Retrieval for Seawinds on QuikSCAT
… retrieval for the SeaWinds scatterometer on the QuikSCAT satellite.</p> <p>Due to its sophistication, field-wise wind retrieval adds computational complexity and intensity. The tradeoffs necessary for practical implementations are examined and quantified. The Levenberg-Marquardt algorithm for …
-
Melt Detection and Estimation in Greenland Using Tandem QuikSCAT and SeaWinds Scatterometers
… backscatter measurements from the SeaWinds on QuikScat (QuikScat) and SeaWinds on ADEOS-2 (SeaWinds) scatterometers are used to classify the melt state and estimate melt severity in Greenland. Backscatter measurements are organized into high temporal and high spatial resolution images created …
-
Observation and Tracking of Tropical Cyclones Using Resolution Enhanced Scatterometry
The QuikSCAT scatterometer provides global daily coverage of oceanic near-surface vector winds. Recently, algorithms have been developed to enhance the spatial resolution of QuikSCAT winds from 25~km to 2.5~km posting. These ultra-high resolution winds are used, in comparison with standard L2B data …
-
A New Method for Melt Detection on Antarctic Ice-Shelves and Scatterometer Calibration Verification
… backscatter measurements from the SeaWinds on QuikScat scatterometer and microwave radiometer measurements from the Special Sensor Microwave/Imager (SSM/I) are used to determine periods of surface melt and freeze in the Antarctic ice-shelves. The normalized radar backscatter (sigma-0) and …
-
Seawinds Radiometer Brightness Temperature Calibration And Validation
… sensor which operates on two satellites; NASA's QuikSCAT launched in June 1999 and on Japan's ADEOS-II satellite launched in December 2002. The purpose of SeaWinds is to provide global measurements of the ocean surface wind vector. On QuikSCAT, a ground data processing algorithm was developed, …
-
A Wind and Rain Backscatter Model Derived from AMSR and SeaWinds Data
The SeaWinds scatterometers aboard the QuikSCAT and ADEOS II satellites were originally designed to measure wind vectors over the ocean by exploiting the relationship between wind-induced surface roughening and the normalized radar backscatter cross-section. Recently, an algorithm for …
-
Wind Scatterometry with Improved Ambiguity Selection and Rain Modeling
… generally accurate, the quality of SeaWinds on QuikSCAT scatterometer ocean vector winds is compromised by certain natural phenomena and retrieval algorithm limitations. This dissertation addresses three main contributers to scatterometer estimate error: poor ambiguity selection, estimate …
-
Monitoring the Antarctic Ice Sheet From Space
… is the demonstration of the stability of NASA's QuikSCAT scatterometer, data from which is used extensively in this thesis and in many other publications. It is shown that QuikSCAT's observation geometry and backscatter instrumentation have remained consistent to great precision throughout its …
-
Improving wind-based upwelling estimates off the west coasts of North and South America
… Navy's global atmospheric (NOGAPS) model, and QuikSCAT satellite-measured winds. Satellite-measured winds, verified with 15 U.S. west coast buoys, were within 1.3 m s-1 and 26ﾰ RMS. Upwelling estimates derived from geostrophic winds using the Pacific Fisheries Environmental Laboratory (PFEL) …
-
Tropical cyclone size in observations and in radiative-convective equilibrium
… First, a climatology of size is created from the QuikSCAT database of near-surface wind vectors for the years 1999-2008. Globally, the distribution of the outer radius is found to be log-normal, with statistically significant variation across ocean basins, but with minimal correlation with various …
-
A comparison of gas exchange models in the estimation of CO2 fluxes in the South Atlantic South of Africa for the summer season of 2008/2009
… Ocean. The wind speed product was extracted from QuikSCAT. Using the data we investigated the sensitivity of the five gas transfer velocity parameterisations to the uncertainty in the wind speed product of 2m.s-1. We found that the Stagnant Film Model was unresponsive. Liss and Merlivat’s (1986) …
-
A Comparison of Gas Exchange Models in the Estimation of CO2 Fluxes in the South Atlantic South of Africa for the Summer Season of 2008/2009
… Ocean. The wind speed product was extracted from QuikSCAT. Using the data we investigated the sensitivity of the five gas transfer velocity parameterisations to the uncertainty in the wind speed product of 2m.s-1. We found that the Stagnant Film Model was unresponsive. Liss and Merlivat's (1986) …
-
Inter-Annual to Inter-Decadal Variability of Upwelling and Anchovy Population off Northern Chile
… functions). The wind field from ERS and QuikSCAT satellite radar scatterometers was analyzed.</p> <p>Variability occurred at four frequency bands: quasi-biennial (2–3 years), ENSO (3–8 years), decadal (9–12 years), and interdecadal (13–25 years). The origin of quasi-biennial variability …
-
Marine weather variability, tropical cyclone prediction and impacts in the Southwest Indian Ocean
… km radius of tropical cyclones, when compared to QuikSCAT satellite winds. As a consequence swell-driven storm surges are also underestimated. Infrared and microwave satellite rainfall comparisons are done and results are presented.
-
Microwave Remote Sensing of the Greenland Ice Sheet: Models and Applications
… Spectral Microwave Imager (SSM/I), SeaWinds on QuikSCAT (QSCAT), and ERS. A new method of melt detection is introduced that is based on a simple physical model relating the moisture content and depth of a layer of wet surface snow to a single channel melt detection threshold. The model can be …
-
Physical controls on spring bloom dynamics in the Irminger Basin, North Atlantic
… reanalysis) and satellite measured wind speed (QuikSCAT), sea surface temperature (SST; AVHRR) and photosynthetically available radiation (PAR; SeaWiFS). The remotely sensed data are complemented by a 1-D vertical mixing model and temperature and salinity profiles from Argo drifting …
-
Microwave Remote Sensing of Saharan Ergs and Amazon Vegetation
… (ESCAT), the SeaWinds scatterometer aboard QuikScat (QSCAT), and the Precipitation Radar (TRMM-PR) aboard the Tropical Rain Monitoring Mission (TRMM) are used to model the backscatter response from sand dunes. Backscatter incidence and azimuth angle variation depends upon the slopes and …
Page 1 of 2