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Precipitable Water Vapor (PWV) is a good source to monitor precipitation. It is defined by the amount of water vapor present in atmosphere. Traditionally, radiosondes and microwave radiometers were used to derive PWV. However, these devices have poor temporal resolutions and high operational costs. Therefore, GPS signal delay is now widely used for such purposes. The main aim of this paper is to study...
Sun-tracking millimeter-wave radiometry exploits the Sun as a beacon source by tracking it along its diurnal ecliptic. The atmospheric brightness temperature is measured by alternately pointing toward-the-Sun and off-the-Sun according to ad hoc switching strategy. By properly developing a retrieval algorithm, we can estimate the atmospheric path attenuation in all-weather conditions. The Langley method,...
Recently, the Optimal Spectral Sampling (OSS) method was implemented in a development version of the Community Radiative Transfer Model (CRTM) at JCSDA. This presentation describes the way that the OSS is implemented in CRTM, and some preliminary evaluation of the performance of the CRTM-OSS in comparison with CRTM-ODPS method. One of the important benefits of the OSS method is its capability to simulate...
Quantitative precipitation estimation (QPE) continues to be one of the principal objectives for weather researchers and forecasters. The purpose of this research is to present the development of a regional dual polarization QPE process known as the RAdar Multi-Sensor QPE (RAMS QPE). This scheme applies the dual polarization radar rain rate estimation algorithms developed at Colorado State University...
To assimilate satellite-based passive microwave observation over heavy clouds and precipitation into numerical weather prediction (NWP) systems and thus to improve the performance of it has become an intensely studied topic. These attempts rely on the development of a radiative transfer (RT) model that accounts for particle scattering and accurately simulates the observation process at an acceptable...
The cloudbow structure is directly related to the retrieval of cloud droplet size distribution (droplet effective radius and effective variance). This study investigated the effect of the cloud optical thickness, ground surface albedo and the above-cloud absorbing dust layer on the cloudbow structure based on the modeled airborne directional polarimetric camera (DPC) measurements, which are simulated...
Most of the climatological studies derived from reanalysis datasets to-date have been presence-based rather than event-based. We have gathered event-based climatological statistics from thirty-seven-plus (37+) years of blizzard-like snowstorms, identified and individually tracked, using hourly high-resolution datasets from the NASA's Modern Era Retrospective-analysis for Research and Applications...
Three years radiosoundings measurement at China were inputted in the Salonen-Uppala cloud detection algorithm to distinguish cloud layers, and to estimate cloud liquid water content therein, then atmospheric transmittances of China at frequencies of the Advanced Microwave Scanning Radiometer - Earth Observing System (AMSR-E) were estimated using MPM and Mie theory. The validation expressed a good...
This research investigated the impact of Radio Occultation (RO) data assimilation on cyclone monitoring. The global positioning system (GPS) radio occultation limb sounding technique has appeared as an efficient global observing system. This technique cans provide good performance in all weather conditions and without calibration requirement. GPS RO data from the Constellation Observing System for...
Extraction of objects such as buildings from very high resolution(VHR) remote sensing imagery is an important task nowadays. In practical application, the extraction precision is normally satisfied through interactive manual input. Therefore, we propose a semi-automatic building extraction framework with an energy minimization model, which includes two stages: the first stage generates the coarse...
There is a significant difference in SWE retrieval performance between the different satellite-based products. The assessment using the Russian and Finnish snow transect data covers an extremely large and varied geographical region and spans a total of ten years (2002–2011). Additionally, the reference data are well suited for assessing coarse resolution data, as they are not point-wise measurements...
We have concluded that before calculation of the AirMOSS project overall RMSE, not only the behavior and location of in-situ soil moisture probes need to be carefully evaluated but also the present error biases—associated with the in-situ probes, radar calibration, vegetation parameterization, forward model inaccuracy, and the inversion algorithm bias—need to be removed. Several measures have been...
Estimation of vertical ground displacements due to seasonal periods of freezing and thawing was carried out on the Selenga River mouth using differential radar interferometry. The results of seasonal radar interferometry measurements for 2008–2010 have been compared with the survey data for 2011, under the assumption that the seasonal deformation is comparable for different years and lie within the...
Water surface extraction using satellite images proves to be of great importance due to its utility in several applications such as land use, floods management and monitoring. Among the wide range of sensors orbiting around the earth, Synthetic Aperture Radar (SAR) proves to be a very effective tool in this context due to its robustness to unfavorable weather conditions and its cloud penetrating capabilities...
Remotely sensed soil moisture data can provide timely, objective and quantitative crop soil moisture information with broad geospatial coverage and sufficiently high resolution observations collected throughout the growing season. This paper evaluates the feasibility of using the assimilated ESA Soil Moisture Ocean Salinity (SMOS) Mission L-band passive microwave data for operational US cropland soil...
This paper presents a generic approach developed to derive surface reflectance over land from a variety of sensors. This technique builds on the extensive dataset acquired by the Terra platform by combining MODIS and MISR to derive an explicit and dynamic map of band ratio's between blue and red channels and is a refinement of the operational approach used for MODIS and LANDSAT over the past 15 years...
Accurate precipitation data with high spatial resolution is important for hydrological, meteorological, and environmental applications. Tropical Rainfall Measuring Mission (TRMM) provides multiple precipitation products with a spatial resolution of 0.25°, and the resolution is too coarse to meet the requirements for hydrological study on local regions and watersheds scale. In this paper, geographically...
The impact of the three dimenstion (3D) effect on the passive microwave rainfall estimations is examined by synthetic retrievals employing a Bayesian methodology. The results showed that the uncertainty in the rainfall estimations due to the 3D effect depended on the viewing directions considered in the a-priori information. It was also found that taking more viewing angles or the azimuth angles in...
Cloud detection is a key processing step before extracting information of earth surface from the earth observation data. Lots of schemes have been developed for cloud detection, static threshold method is the main method that is widely used in cloud detection. However, for the huge difference between different land objects, it is much difficult to find a proper threshold to detect the cloudy pixel...
Accurate rainfall estimations based on ground-based rainfall observations and satellite-based rainfall measurements are essential for hydrological and environmental modeling in the Qaidam Basin of China. We evaluated the accuracy of daily scale Tropical Rainfall Measuring Mission (TRMM) rainfall products in the Qaidam Basin. A geographically weighted regression (GWR) was used to estimate the spatial...
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