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The Meteor-M N 2 spacecraft with microwave radiometer MTVZA-GY has been launched on July 8, 2014 on sun-synchronous orbit at an altitude of 830 km. MTVZA-GY is a 29 channel microwave imager/sounder for remote sensing of the ocean and land surface parameters as well as for measuring total atmospheric water vapor content, total cloud liquid water content, air temperature and humidity profiles. MTVZA...
This paper presents a numerical study of microwave brightness temperature of residual foam cover on ocean surface. The foam layer is modeled using Kelvin's Tetrakaidecahedron structure. Absorption and scattering of the foam layer, i.e. the layer phase matrix, are calculated using a multilevel UV method to accelerate method of moment (MoM) solution of Maxwell's equations. Matrix doubling method, which...
Scene imaging simulation is an indispensable work in passive millimeter-wave object detection and remote sensing. In this paper, a 3-D scene simulation model of passive millimeter-wave imaging based on ray-tracing is presented, with consideration of the essential affecting factors such as multiple reflections, sky radiation, polarization rotation and antenna pattern smoothing. In order to accelerate...
SMOS is the acronym for the Soil Moisture and Ocean Salinity mission by the European Space Agency (ESA) [1]. Its single payload, the Microwave Imaging Radiometer using Aperture Synthesis (MIRAS), was successfully launched in November 2009. Along more than six years of operation, SMOS calibration and imaging algorithms have undergone a continuous evolution to further improve the accuracy of the retrieved...
Aperture synthesis with high spatial resolution would seriously increase the hardware requirements and system complexity. To reduce the system complexity, Rotating mirrored aperture synthesis (RMAS) that combines the antenna array rotation with mirrored aperture synthesis was proposed to reduce the number of antennas. In this paper, the sieving method is presented to optimize the array configuration...
SMAP brightness temperature observations are assimilated within the Canadian Land Data Assimilation System, together with screen-level observations, and the resulting soil moisture and surface temperature analyses are evaluated in the context of Environment Canada's Regional Deterministic Prediction System.
Sea ice is an important quantity for the radiation budget of the Earth's climate system. In this paper we present a comparison of SMAP and SMOS measured brightness temperatures and translate a validated retrieval algorithm for the thickness of thin sea ice from SMOS to SMAP radiometer observations. For October to December all observations of SMAP in forward and backward direction are compared as daily...
The Ultra-wideband Software Defined Radiometer (UWBRAD) for ice sheet internal temperature sensing is designed to provide observations of ice sheet brightness temperatures from 500-2000 MHz. This presentation reports on current status of the instrument development, experimental results obtained to date, and plans for a September 2016 airborne deployment over Greenland.
The brightness temperature of snow-covered terrain was monitored from January through April 1985 using tower-based radiometers operating at 1, 16.5, and 37 GHz (vertical and horizontal polarization) in southern Finland. Ground truth data on snow, soil and weather were collected. Layered dielectric, extinction and wetness information on snow at the test site was obtained with free-space transmission...
This paper presented a pixel-based statistical regression method based on a high-resolution snow depth product to improve the accuracy of passive microwave snow depth retrievals. The statistical regression relation was established based on a linear relationship between the snow depth and the brightness temperature (TB) difference. The coefficients of these regression equations were derived using the...
Freeze and thaw (FT) processes have profound impact on the terrestrial water cycle, net primary productivity, carbon cycle, surface energy budget and hence the global climate system. The available passive microwave based FT states data are basically developed from brightness temperatures, which themselves affected by atmospheric water vapor content. Since land surface emissivity estimates derived...
The L-band (1 – 2 GHz) microwave remote sensing has been widely acknowledged as the most promising method to monitor regional to global soil moisture. Consequently, the Soil Moisture Active Passive (SMAP) satellite applied this technique to provide global soil moisture every 2 to 3 days. To verify the performance of SMAP, the fourth and fifth campaign of SMAP Experiments (SMAPEx-4 & -5) were carried...
QP model with dual-channel algorithm could accurately represent the effect of surface roughness on emission at different polarization under big view angle. The purpose of this paper is to estimate long temporal series soil moisture product based on the QP algorithm, and compared it with JAXA, LPRM in Genhe basin. The results indicate that QP retrieval values are closest to the ground data but it have...
Sea surface salinity (SSS) has a profounding influence on the the exchanges of matter and energy at the air-ocean interface. It is also a driving force for ocean circulations. The capability of accurate measurement of SSS with high spatial and temporal resolution shall be a desirable boost to the global climate models. The scientific missions Soil Moisture and Ocean Salinity (SMOS) [1] and Aquarius...
Land data assimilation system (LDAS) has been a powerful tool to optimally combine the advantages of microwave remote sensing and land surface model together and then improve the accuracy of land surface fluxes and status estimation. In this study, we developed a land data assimilation system, in which the water imbalance is constrained by using a multiply times assimilation approach. The first step...
The coarse spatial resolution of microwave radiometer measurements hinders its application on land and sea surface parameters estimation. Measurements therefore require better spatial resolution to improve parameters estimation with enhanced resolution and accuracy. In this paper, a linear unmixing method is presented to downscale brightness temperatures (TB) for accurate land surface parameters retrieval...
The SMAP Level 4 soil moisture (L4_SM) product provides global estimates of surface and root zone soil moisture, along with other land surface variables and their error estimates. These estimates are obtained through assimilation of SMAP brightness temperature observations into the Goddard Earth Observing System (GEOS-5) land surface model. The L4_SM product is provided at 9 km spatial and 3-hourly...
This work is devoted to describe the new processing techniques that are being conceived, developed and implemented at the Barcelona Expert Centre (BEC) for the generation of sea surface salinity (SSS) maps from the Soil Mooisture and Ocean Salinity (SMOS) mission. Several algorithms to mitigate the ripples and sidelobes present in the SMOS brightness temperature (TB) images, to characterize the spatial...
A partially coherent low frequency microwave emission model for polar ice sheet is developed to operate from 0.5GHz to 2.0GHz predicting brightness temperatures. The emission from polar ice sheet over the wide frequency band is shown to be correlated with its temperature profile and affected by its density fluctuations. The density fluctuations creating weakly reflective internal interfaces cause...
Extreme weather observations with temporal resolution of ∼15–30 minutes and spatial resolution of ∼15–30 km are required to improve forecasting of mesoscale severe weather events. Due to recent advances in microwave receiver and filter technology, the fleet concept of ∼30–40 CubeSat nanosatellites has been identified as an alternative but cost effective means to meet the requirements. OSSEs of CubeSat...
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