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In this paper we present a combined strategy for the retrieval of atmospheric profiles from infrared sounders. The approach considers the spatial information and a noise-dependent dimensionality reduction approach. The extracted features are fed into a canonical linear regression. We compare Principal Component Analysis (PCA) and Minimum Noise Fraction (MNF) for dimensionality reduction, and study...
The Ultra-Wideband Microwave Radiometer is a novel pseudo-correlation radiometer design measuring scene brightness temperatures from 0.5–2 GHz created under NASA's Instrument Incubator Program. This document analyzes the design and operation of the radiometer, the accuracy and stability of the brightness temperatures it produces, and presents initial results from a field campaign conducted in Greenland...
In this paper we discuss a polarimateric calibration technique applied on the Soil Moisture Active Passive (SMAP) L-band radiometer. We take advantage of the SMAP antenna rotation and varying incidence angle during pitch maneuvers performed by the spacecraft for periodic cold-sky calibration. We present initial comparisons between the polarization corrected ocean signal at various incidence angles...
The Advanced Baseline Imager (ABI) is successfully operating on orbit, aboard the Geostationary Operational Environmental Satellite 16 (GOES-16). When GOES-16 becomes an operational satellite for NOAA later in 2017, it will begin a new era for the United States in the quality and quantity of geostationary weather observations. Not only does ABI provide more than three times the bands, four times the...
The spatial and temporal distribution of ROS across the Canadian Arctic Archipelago (CAA) remains poorly understood owing to their sporadic nature in time and space. In this study, we highlight the distribution and evolution of ROS occurrences inventoried since 1984 at 14 Environment and Climate Change Canada (ECCC) weather stations in the CAA. We introduce an adaptation of the detection algorithm...
Using the dielectric/permittivity spectra from liquid hydrocarbons to characterize their composition requires knowledge of their geochemistry and the geological processes that formed them. Complex permittivity measurements of two crude oils and gas condensate at 25°C were conducted using two state of the art multipoint resonant cavities. High accuracy permittivity values were obtained for nine different...
A new multilayer IST-albedo Moderate Resolution Imaging Spectroradiometer (MODIS) product of Greenland was developed to meet the needs of the ice sheet modeling community. The multiple layers of the product enable the relationship between IST and albedo to be evaluated easily. Surface temperature is a fundamental input for dynamical ice sheet models because it is a component of the ice sheet radiation...
It has recently been found that the visibility denormalization process introduces a spatial error distribution due to small sporadic offset jumps in the PMS detectors. The radiometric impact of this error at system level is very low. However, due to the good performance of the SMOS instrument, a study has recently been conducted to evaluate the amplitude of such visibility errors and develop a mitigation...
The Cyclone Global Navigation Satellite System (CYGNSS) uses the Global Positioning System (GPS) constellation (32 satellites) as the active source in a bi-static radar configuration, with CYGNSS acting as the passive radar receiver. A knowledge of Equivalent Isotropically Radiated Power (EIRP), based on transmit power and antenna pattern of GPS satellites, is of great importance in the accurate calibration...
A new space-borne mission based on a multi-channel microwave radiometer in the frequency range 0.5–2 GHz as been recently approved by the Italian Space Agency for a preliminary concept study. The innovative instrument will be devoted to the study of the Cryosphere and in particular on sea ice volume, ice sheet temperature and soil status. Scientific objectives and first mission concept are presented...
NASA's Soil Moisture Active and Passive (SMAP) satellite was launched in January 2015 to provide global measurements of soil moisture and freeze/thaw state. Soil moisture products are derived from SMAP radiometer measurements acquired at L Band (1.4 GHz). Even though this is a protected band, unauthorized transmitters emitting either within the band or in adjacent bands cause radio frequency interference...
Radio-Frequency Interference (RFI) is a growing problem for applications based on the Global Navigation Satellite Systems (GNSS), including Earth observation using GNSS — Reflectometry (GNSS-R). Nowadays, many efforts are being concentrated to develop RFI signal detectors with high sensitivity, which can help to control the proliferation of RFI generators or jammers. This work aims at designing and...
In this paper, we study the effect of layered snow in alpine regions on microwave emission at Ku and Ka bands, using both experimental data and model simulations. A recent implementation of the multi-layer dense-medium radiative transfer model (DMRT) under the quasi-crystalline approximation (ML-QCA) was used to account for the effects of snow layers on the emission from dry snow covers. Model simulation...
A useful means of calibrating remote sensing retrieval algorithms is by means of a time series of ground truth measurements at specific locations. For snow depth (SD) or snow water equivalent (SWE), ground truth regarding snow density and snow grain size stratigraphy is provided manually via snow pits. While the data is of high quality, this method is time consuming and labor intensive and thus precludes...
SnowEx is a winter airborne and field campaign designed to measure snow-water equivalent in forested landscapes. A major focus of Year 1 (2016–17) of NASA's SnowEx campaign will be an extensive field program involving dozens of participants from U.S. government agencies and from many universities and institutions, both domestic and foreign. Along with other instruments, two infrared (IR) sensors will...
Landscape freeze/thaw (FT) state is a key variable in Earth's carbon cycle. NASA's Soil Moisture Active Passive (SMAP) satellite mission, launched in January 2015, provides global retrievals of FT state every two to three days. Validating SMAP FT observations with in-situ observations is difficult due to the substantial scale mismatch between a point estimate and a satellite footprint, inducing “representativeness...
Thermal anomalies might be an important precursor of earthquake, however not fully proved. In this study, time series of Land Surface Temperature (LST) data spanning over 14 years have been processed and analyzed to locate possible anomalous variations prior to the 2016 Menyuan Ms6.4 earthquake (China). A smoothing procedure have been applied to exclude the seasonal or annual effects from the LST...
Soil moisture is of fundamental importance to many hydrological, biological and biogeochemical processes, plays an important role in the development and evolution of convective weather and precipitation, and impacts precision agriculture, water resource management, and flood runoff prediction. The launch of NASA's Soil Moisture Active/Passive (SMAP) mission in 2015 provide new passive global measurements...
Tracking the radiometer calibration stability is very important for climate monitoring radiometers as long term accuracy of observations is needed to create reliable climate models. This presentation discusses the advantages of 3-point onboard calibration techniques over 2-point methods to track radiometer calibration stability.
The baseline science objective of the NASA Soil Moisture Active Passive (SMAP) mission is to produce a daily landscape freeze/thaw state for the region north of 45° N latitude with a mean spatial classification accuracy of 80% and 2–3 day average intervals separated by AM and PM overpasses [1]. Following the loss of the SMAP radar in July 2015, radiometer inputs were used to develop a standard freeze/thaw...
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