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The database helps to better understand and quantify the effect of F/T and snow on the L-Band signal. The information will be useful for the validation and calibration of satellite based products. The database will also be used to validate and calibrate different L-Band snow emission models [3–4–5].
In this paper, we propose a new approach for improving boreal forest soil moisture estimation using L-band microwave radiometer. The effect is achieved by introducing improved description of forest canopy contribution from multisensor SAR measurements.
The Soil Moisture Active Passive (SMAP) mission, launched January 31, 2015, provides global observations of 1.4 GHz Earth thermal emissions from space [1] through its L-band radiometer. Although SMAP's radiometer passband lies within the protected 1.4–1.427 GHz band, both unauthorized in-band transmitters as well as out-of-band emissions from transmitters operating at frequencies adjacent to this...
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,...
In this paper the results of multi-frequency (at 5.6GHz, 15GHz and 37GHZ) and polarization measurements of clear and cloudy sky apparent temperatures are presented, measured under various observation angles. The results have been obtained during the measurements carried out in Armenia from the measuring complex built under the framework of ISTC Projects A-872 and A-1524. The measurements were carried...
Full Polarization Interferometric Radiometer (FPIR) is a one-dimensional full polarization Interferometric radiometer for the Sea Surface Salinity (SSS). A ground-based prototype has been developed to demonstrate the concept and performance of the instrument. To achieve the SSS measurement accuracy, a new calibration system has been designed for FPIR. And a new calibration procedure has been developed...
A variational method based on 1Dvar is proposed to retrieve Integrated Precipitable Water vapor (IPW) in typhoon area from brightness temperatures measured by the Microwave Humidity and Temperature Sounder (MWHTS) on the Chinese Fengyun 3C (FY-3C) polar-orbit meteorological satellite. Water vapor values provided by European Centre for Medium-Range Weather Forecasts (ECMWF) were used as background...
The radiometer Subband calibration and calibration drift correction have been successfully used in the released radiometer L1B data product. Although their performances satisfy the requirements, they are still under continuing analysis to find their remaining uncertainty. The progress will be presented besides the current performance.
We developed a cost-effective monitoring tool to quantify forage production across landscapes,that are driven with satellite remote sensing data and calibrated with a statewide point dataset of peak forage production measurements. Our results showed that the satellite-derived annual forage production correlated well with contemporaneous in-situ forage measurements; it also captured spatial and temporal...
Significant changes have occurred in permafrost and seasonally frozen soils in the Tibetan Plateau (TP) during the last few decades, with potential influence on regional climate, hydrological and ecosystem processes. Land surface temperature (LST) is closely associated with surface energy balance, thus is a critical parameter affecting the frozen soil thermodynamics. Satellite remote sensing provides...
Surface soil moisture (SSM) is a significant variable in various fields of science. This paper aims to analyze and improve a SSM retrieval model to apply it to estimate SSM at the regional scale. Firstly, the model parameters were been analyzed. The rotation angle was transformed into exponential form and the ellipse center horizontal coordinate was decreased for the improved SSM retrieval model....
Though, solar radiation data is not available in maximum weather stations, it is an important parameters for biogeochemical models hence there is an increasing demands of available energy data. The seasonal model described here can be used for a rough estimation of maximum available solar energy in nearby areas of the measuring station in clear sky condition with minimum calculation and efforts. Other...
The Tropopause in Tibet has complex and variable characteristics due to its harsh natural conditions, while it is hard to monitor the tropopause in Tibet from traditional techniques. Nowadays, the high resolution data from GPS Radio Occultation provide a unique opportunity to monitor the tropopause variation, particularly over Tibet. In this paper, the high resolution cold-point tropopause (CPT) in...
Soil respiration (Rs) is a major CO2 flux within terrestrial ecosystems. This study examine the feasibility of applying HJ-1 CCD data to analyze the growing-season variations of Rs in two irrigated cropland ecosystems. At growing season time scale, crop biophysical parameters, such as leaf chlorophyll content (Chlleaf) and green leaf area index (GLAI), explained most Rs variation in the maize and...
The Weihai area in Shandong province has undergone intensive changes of the landscape over the past years. The city has expanded to a high percentage but is still characterized by a huge number of lakes and surrounding coastal waters (case-II). In the study, we investigated the temperature changes of those lakes and the coastal zones as well as of some features at land over the past 20 years. We were...
Recently, the National Oceanic and Atmospheric Administration (NOAA) performed sea surface temperature (SST) reanalysis (RAN1) from seven AVHRR/3s onboard NOAA-15 to -19 and Metop-A and -B, from 2002-present using operational L1b input. The time series of clear-sky ocean brightness temperatures (BTs) and derived SSTs were found to be unstable. While the SSTs were empirically stabilized against in...
In this paper the results of radiometric measurements of clear sky and various types of clouds brightness (apparent) temperatures will be presented, measured at various frequencies and polarizations. The results have been obtained during the measurements carried out in Armenia from the measuring complex built under the framework of ISTC Projects A-872 and A-1524. The measurements were carried out...
In this paper we discuss the steps taken for the calibration and validation of the Soil Moisture Active Passive (SMAP) L-band radiometer. We discuss the use of multiple vicarious sources such as the global ocean mean and celestial cold-sky emissions along with various spacecraft maneuvers to calibrate out gain, offset, antenna pattern of the radiometer. We present initial validation comparison of...
For the retrieval of satellite-derived sea surface temperature (SST), an empirical regression algorithm has been widely used so far despite its local bias. Recently, as fast radiative transfer model (RTM) enable near real-time simulations of clear-sky BTs, a hybrid SST algorithm has been suggested, which is based on regression between the incremental values (satellite-observed BT minus first-guess...
In order to estimate Chlorophyll-a concentrations at high spatial-temporal resolution accurately over bay systems in the western Gulf of Mexico, a 2-step remote sensing algorithm using observations from the Medium Resolution Imaging Spectrometer (MERIS) is developed. Here, the approach is tested in Galveston Bay. First, atmospheric correction for the MERIS reflectance is performed to improve the quality...
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