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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.
Surface soil moisture was retrieved globally by systematically correcting for the effects of vegetation and soil surface roughness. The retrieval is enabled by employing physical-models of radar forward scattering for individual vegetation types to account for vegetation scattering and absorption, and by constraining the surface roughness effect using time-series observations. The L-band SMAP multi-polarized...
Identification of high potential risk and susceptible zones for natural hazards of geological origin is one of the most important applications of advanced remote sensing technology in tropical environments. Yearly, several landslides occur during heavy monsoon rainfall in Kelantan river basin, Peninsular Malaysia, which are obviously connected to geological structures and topographical features of...
Scanning L-band Active/Passive (SLAP) is an airborne remote sensing instrument developed at NASA Goddard Space Flight Center specifically as an airborne simulator of the Soil Moisture Active/Passive (SMAP) satellite instrument suite, for remote sensing of soil moisture, freeze-thaw state, ocean salinity, sea ice, and other physical phenomena that display characteristics at microwave L-band. This paper...
Recent theoretical and experimental studies have indicated the feasibility of passive microwave L-band observations for observing dry snow cover characteristics, namely snow density in the lower approx.. 10 cm of the snowpack. The sensitivity of L-band emission to snow density is based on the dual influence of refraction and impedance matching on observed brightness temperature with changing effective...
An experiment to examine the detectability of volcanic ash cover and its thickness by using L-band synthetic aperture radar (SAR) was carried out. Test sites with 0, 10, 20, and 40 cm ash layers were developed. PALSAR-2 and Pi-SAR-L2 observations were carried out several times with and without the ash cover. The PALSAR-2 backscatter coefficients in HH polarization, σHH0, for soil with ash layers are...
The paper reports on measurements performed with a simultaneous L and X band, fully polarimetric airborne SAR system, the MetaSAR-XL model produced by MetaSensing. One of those systems is owned and operated by Five Stars Electronic Technology and Tianjin SARruide Technology in China. A number of results of campaigns performed in Europe and People's Republic of China are reported, including interferometric...
In recent years, large number of Interferometric SAR applications in earthquake, cryosphere and tectonic geodesy show the great needs for ionospheric effect correction [1–4]. Several approaches, which mainly include the split spectrum InSAR technique, the Faraday rotation based method and the azimuth shift based method (the Multiple Aperture Interferometric and conventional azimuth shift) have been...
The forest aboveground biomass and its dynamics are essential for researches of carbon cycling. The estimation of forest aboveground biomass is an important topic in the application of remote sensing. However, the estimation accuracy is limited by the lack of forest structures. Recent progresses over the past decade in the estimation of forest biomass from remote sensing data was mainly due to the...
A fundamental requirement for coherent processing of repeat pass SAR data stacks is to have precise knowledge of the relative position of each track. Indeed, sub-wavelength position errors give rise to residual phase screens among different passes, which hinder coherent applications. In this paper we describe an approach to estimate and remove phase screens by exploiting distributed targets, based...
Verifying the calibration of the SMAP radiometer over land observations is an important mission requirement. Inter-comparison of L-band brightness temperature observations from different satellites (SMAP, SMOS and Aquarius) is a useful tool for radiometer calibration. Brightness temperatures observations made at the same frequency, polarization, incidence angle and coincident in time and location...
Three L-band radiometers have been observing the Earth in order to retrieve soil moisture and ocean salinity. They use different instrument configurations and calibration and retrieval algorithms. In any case, the brightness temperature retrieved at the Earth surface should be consistent between all instruments. One reason for inconsistency would be the use of different approaches for the instrument...
A combined L-band active and passive sensor for space-based ocean salinity observation has been proposed in MIRSlab, CAS [1] [2]. A ground-based prototype has been developed to demonstrate the concept and performance of the instrument. The experimental result of the passive part of the prototype, the L-band 1-D synthetic aperture radiometer, has been introduced in this paper.
The NASA Soil Moisture Active Passive (SMAP) mission aims at producing low (36 km) and high-resolution (9 km) global maps of surface soil moisture based on L-band radiometer and radar/radiometer measurements, respectively. In this research study, results of applying a novel retrieval algorithm, the so-called Multi-Temporal Dual Channel Algorithm (MT-DCA) to the first year of SMAP observations are...
The Soil Moisture Active Passive (SMAP) mission launched on Jan 31, 2015. The mission employs L-band radar and radiometer measurements to estimate soil moisture with 4\% volumetric accuracy at a resolution of 10 km, and freeze-thaw state at a resolution of 1–3 km [1]. Immediately following launch, there was a three month instrument checkout period, followed by six months of level 1 (L1) calibration...
The MICAP(microwave imager combined active and passive), which has been selected to be a candidate payload for future Chinese ocean salinity mission, contains an L-band digital beam forming(DBF) scatterometer for the purpose of elimination of ocean surface roughness and wind retrieving. In this paper, data pre-processing flow for this scatterometer to obtain data ready for sea surface salinity and...
Compared with single-polarization synthetic aperture radar (SAR), full-polarization SAR can not only collect the echo intensity of backscattered from the sea surface, but also can collect the phase information. For oil spill detection, polarimetric SAR has more advantages. Features extraction is a crucial step for oil spill discrimination. In this paper, eight kinds of polarimetric features, such...
In this paper, an active layer thickness (ALT) retrieval algorithm is presented wherein time-series of P- and L-band radar observations are used simultaneously to retrieve the depth from ground surface to permafrost table. Several model assumptions for two active layer soil conditions (maximum thaw and partially frozen) are made based on observations of in situ soil temperature and soil moisture data...
Water Cycle Observation Mission (WCOM) is an earth science mission proposed and focused on the research of water cycle under global change. With its three dedicated designed main payloads, WCOM can achieve synchronized observation on a group of global water cycle key parameters, including soil moisture, ocean salinity, snow water equivalent, soil freeze-thaw, atmospheric water vapor, precipitation...
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