David Long

• Doctor of Philosophy
• Managing Director at Brigham Young University

SASS collected nominally 50 km resolution normalized radar cross section (σo) from four different azimuth angles over two ∼500 km wide swaths with. All four antennas were dual-polarized, resulting in 8 ‘beams’. SASS employed long, fan-beam antennas with narrow (∼10 km) narrow beamwidths. Along-beam resolution was achieved using 4.8 ms continuous wa...

NSCAT (Graf et al.,1998) collected nominally 25 km resolution normalized radar cross section (σo) from 6 different azimuth angles over two 600 km wide swaths with a 300 km gap. Two of the antennas were dual-polarized. NSCAT employed long, fan-beam antennas with narrow (∼ 7 km) beamwidths. Along-beam resolution was achieved using 5 ms continuous wav...

We use enhanced-resolution L-band radar backscatter and brightness temperature image time series generated from observations collected by NASA’s Soil Moisture Active Passive (SMAP) mission to map the extent and physical characteristics of an expansive perennial firn aquifer recently identified in the Wilkins Ice Shelf, Antarctic Peninsula. Empirica...

Long-term studies of climate change can benefit from a retrospective analysis of past satellite missions. To facilitate such studies, in this paper we describe two new radar backscatter products derived from the Seasat-A Scatterometer System (SASS) and the NASA Scatterometer (NSCAT). Operating at Ku-band (14.6 and 13.995 GHz, respectively), the two...

NASA's Soil Moisture Active Passive (SMAP) mission originally included both passive and active L-band measurement capability. It was the first satellite instrument to provide global L-band radar observations of normalized radar cross section ( $\sigma ^{o}$ ) at multiple resolutions. The SMAP radar collected high resolution ( $\sim$ 1–3 km) synth...

This data set contains twice-daily synthetic aperture radar (SAR) and enhanced-resolution scatterometer radar backscatter derived from SMAP radar data. Data are available on the Northern Hemisphere, Southern Hemisphere, Temperate, and Mid-Latitude (sub-set of Global) EASE-Grid 2.0 projections and as either 25 km or 3.125 km resolution grids. This n...

Radiometric and radar data from NASA’s Soil Moisture Active Passive (SMAP) satellite are presented in a study of the Ross ice shelf, Antarctica. L-band brightness temperature ( $T_{B}$ ) patterns compare favorably to the outflow patterns from East and West Antarctica. Cooler $T_{B}$ is associated with the broad outflow from West Antarctic ice st...

Urban settlements are rapidly growing outward and upward, with consequences for resource use, greenhouse gas emissions, and ecosystem and public health, but rates of change are uneven around the world. Understanding trajectories and predicting consequences of global urban expansion requires quantifying rates of change with consistent, well-calibrat...

The NASA-sponsored Calibrated Enhanced-Resolution Passive Microwave Daily EASE-Grid 2.0 Brightness Temperature (CETB) and Soil Moisture Active Passive (SMAP) Radiometer Twice-Daily rSIR-Enhanced Equal-Area Scalable Earth (EASE)-Grid 2.0 Brightness Temperature (SETB) projects team has processed a multi-sensor, multi-decadal, image time series of enh...

Perennial firn aquifers are subsurface meltwater reservoirs consisting of a meters-thick water-saturated firn layer that can form on spatial scales as large as tens of kilometers. They have been observed within the percolation facies of glaciated regions experiencing intense seasonal surface melting and high snow accumulation. Widespread perennial...

Mapping the spatial extent of recently identified englacial hydrological features (i.e., ice slabs and perennial firn aquifers) formed by meters-thick water-saturated firn layers over the percolation facies of the Greenland Ice Sheet using L -band microwave radiometry has recently been demonstrated. However, these initial maps are binary, and do...

Firn aquifers are subsurface reservoirs consisting of a meters-thick water-saturated firn layer. Here, we present observations identifying firn aquifers on current and former ice shelves in the northwestern Antarctic Peninsula based on satellite microwave radiometry, radar scatterometry, synthetic aperture radar, and visible imagery as well as airb...

Perennial firn aquifers are subsurface meltwater reservoirs consisting of a meters-thick water-saturated firn layer that can form on spatial scales as large as tens of kilometers. They have been observed within the percolation facies of glaciated regions experiencing intense seasonal surface melting and high snow accumulation. Widespread perennial...

Enhanced-resolution L-band brightness temperature (TB) image time series generated from observations collected over the Greenland Ice Sheet by NASA's Soil Moisture Active Passive (SMAP) satellite are used to map Greenland's perennial firn aquifers from space. Exponentially decreasing L-band TB signatures are correlated with perennial firn aquifer a...

Abstract. Enhanced-resolution L-band brightness temperature (TB) image time series collected over the Greenland ice sheet by NASA’s Soil Moisture Active Passive (SMAP) satellite are used to map Greenland’s perennial firn aquifers from space. Exponentially decreasing L-band TB signatures are correlated with perennial firn aquifer areas identified vi...

This European project implied that backscatter and wind product were kindly made available by the Chinese National Satellite Ocean Application Service (NSOAS), which form the basis of all activities described in this report. Moreover, the processing software for the HY-2B wind products is an update of the standard PenWP software, which has been est...

We present satellite-derived observations of firn aquifers on ice shelves in Antarctica. Our observations are based on analysis of microwave time series collected by NASAs Soil Moisture Active Passive (SMAP) satellite and radio echo sounding data collected by the Multichannel Coherent Radar Depth Sounder (MCoRDS) as part of NASAs Operation IceBridg...

The NASA-sponsored Calibrated Passive Micro-wave Daily Equal-Area Scalable Earth Grid 2.0 Brightness Temperature (CETB) Earth System Data Record Project team has generated a multisensor, multidecadal time series of high-resolution radiometer products designed to support climate studies. This project uses image reconstruction techniques to generate...

Recent ice shelf disintegrations on the Antarctic Peninsula and subsequent increases in ice sheet mass loss have highlighted the importance of tracking ice shelf stability with respect to surface melt ponding and hydrofracture. In this study, we use active microwave scatterometry in time-series to estimate melt season duration, and winter backscatt...

This paper describes the development of, and the methodology for, a new, consolidated Brigham Young University (BYU)/National Ice Center (NIC) Antarctic iceberg tracking database. The new database combines daily positional data from the original BYU daily iceberg tracking database derived from scatterometers, and the NIC’s weekly Antarctic iceberg...

Prospective authors are requested to submit new, unpublished manuscripts for inclusion in the upcoming event described in this call for papers.

The concept of isohydry/anisohydry describes the degree to which plants regulate their water status, operating from isohydric with strict regulation to anisohydric with less regulation. Though some species level measures of isohydry/anisohydry exist at a few locations, ecosystem-scale information is still largely unavailable. In this study, we use...

Motivated by the desire to gain insight into the details of conventional airborne synthetic aperture radar (SAR) imaging of trees, a ground-based SAR system designed for short-range three-dimensional (3D) radar imaging is developed using a two-dimensional (2D) synthetic aperture. The heart of the system is a compact linear frequency modulation-cont...

Satellite microwave sensors, both active scatterometers and passive radiometers, have been systematically measuring near-surface ocean winds for nearly 40 years, establishing an important legacy in studying and monitoring weather and climate variability. As an aid to such activities, the various wind datasets are being intercalibrated and merged in...

Wind scatterometers were originally developed for observation of near-surface winds over the ocean. They retrieve wind indirectly by measuring the normalized radar cross section ( $\sigma ^o$ ) of the surface, and estimating the wind via a geophysical model function relating $\sigma ^o$ to the vector wind. The $\sigma ^o$ measurements have proven t...

The Ku-band Oceansat-2 Scatterometer (OSCAT) is very similar to the Quick Scatterometer (QuikSCAT), which operated from 1999 to 2009. OSCAT continues the Ku-band scatterometer data record through 2014 with an overlap of 19 days with QuikSCAT's mission in 2009. This letter discusses a particular climate application of the time series for sea ice ext...

This paper compares the performance and tradeoffs of various backscatter imaging algorithms for the SeaWinds scatterometer when multiple passes over a target are available. Reconstruction methods are compared with conventional gridding algorithms. In particular, the performance and tradeoffs in conventional “drop in the bucket” (DIB) gridding at th...

Satelliteborne C-band scatterometer measurements of the radar backscatter coefficient $(\sigma^{0})$ of the Earth can be used to estimate soil moisture levels over land. Such estimates are currently produced at 25- and 50-km resolution using the Advanced Scatterometer (ASCAT) sensor and a change detection algorithm originally developed at the Vienn...

For most land and ice surfaces, the measured radar backscatter at the spatial resolution of a wind scatterometer is insensitive to the azimuth angle. However, for regions of East Antarctica, the backscatter strongly depends on the azimuth angle. This relationship between backscatter and azimuth angle is often modeled with a Fourier series. Although...

The standard ocean wind product from the Advanced Scatterometer (ASCAT) is retrieved on a 12.5-km grid. Ultrahigh-resolution (UHR) processing enables ASCAT wind retrieval on a high-resolution 1.25-km grid. Ideally, such a high-resolution grid allows for improved analysis of winds with high spatial variability, such as those in near-coastal regions...

The Advanced SCATterometer (ASCAT) measurement spatial response function (SRF) relates the weighted contribution of every location within the measurement footprint to the measured normalized radar cross section σ°. The SRF results from a combination of the antenna response and the onboard processing and is computed during ground processing by model...

RapidScat, which is a Ku-band scatterometer mounted on the International Space Station, observes the Earth's surface in a non-sun-synchronous orbit allowing for different local time-of-day (LTOD) observations as the orbit progresses. The unique orbit and different LTOD observations provide surface observations that are composited to describe the di...

Sampling plays a critical role in remote sensing and signal analysis. In conventional sampling theory, the signal is sampled at a uniform rate at a minimum of twice the signal bandwidth. Sampling with an aperture function requires a fixed-aperture function, which can be removed by deconvolution after signal reconstruction. However, in some cases, t...

Launched in September 2014, RapidScat is currently operating on the International Space Station (ISS). RapidScat estimates ocean vector winds via the measurement of the normalized radar coefficient (σ0) of the ocean's surface. Measurements are also collected over land. The ISS orbit permits, for the first time, the observation of the diurnal variat...

This paper considers some of the issues of radiometer brightness image formation and reconstruction for use in the NASA-sponsored Calibrated Passive Microwave Daily Equal-Area Scalable Earth Grid 2.0 Brightness Temperature Earth System Data Record project, which generates a multisensor multidecadal time series of high-resolution radiometer products...

http://www.nap.edu/catalog/21729/a-strategy-for-active-remote-sensing-amid-increased-demand-for-radio-spectrum

This paper presents a generalized treatment of image formation for a linear-frequency-modulated continuous wave (LFM-CW) synthetic aperture radar (SAR) signal, which is a key technology in making very small SAR systems viable. The signal model is derived, which includes the continuous platform motion. The effect of this motion on the SAR signal is...

This article explores the SAR back-projection algorithm for stripmap image formation and its characteristics. The article provides a derivation of generalized time-domain back-projection from first principles. It shows that back-projection may be considered an ideal matched filter for SAR. The article presents an analysis of the sensitivity of back...

Synthetic aperture radar (SAR) interferometry uses the phase difference between two SAR antennas to obtain an elevation estimate of the imaged terrain. Using an initial digital elevation model (DEM), the time-domain backprojection algorithm implicitly removes the terrain height phase from images during image formation. The use of a DEM during image...

QuikSCAT backscatter is generally higher over urban areas than surrounding vegetated areas. Azimuthal anisotropy has been observed over some urban areas, but the strength of the azimuthal anisotropy in the urban backscatter signal has not been well quantified. This study investigates radar azimuthal anisotropy in urban areas. QuikSCAT L1B σ0 observ...

The field of wireless communications has benefited from multiple-input and multiple-output (MIMO) techniques. As researchers seek to apply MIMO (multistatic) techniques to radar and specifically to synthetic aperture radar (SAR), a key factor in determining MIMO application and performance is the level of correlation of signals from different recei...

Arctic sea ice can be classified as first-year (FY) or multiyear (MY) based on data collected by satellite microwave scatterometers. The Oceansat-2 Ku-band Scatterometer (OSCAT) was operational from 2009 to 2014 and is here used to classify ice as FY or MY during these years. Due to similarities in backscatter measurements from sea ice and open wat...

A wind scatterometer measures the normalized radar cross section σ of the Earth's surface in order to estimate the ocean near-surface wind. Each measurement is the weighted integral of σ over an area, so samples of σ are filtered by a measurement spatial response function (SRF). Enhanced-resolution σ data may be produced from σ measurements and the...

Polar sea ice is an important input to global climate models and is considered to be a sensitive indicator of climate change. While originally designed only for wind estimation, radar backscatter measurements collected by wind scatterometers have proven useful for estimating the extent of sea ice. During the Quick Scatterometer (QuikSCAT) mission,...

Originally designed for wind velocity estimation over the ocean, scatterometers have been applied to weather forecasting, global climatological studies, and monitoring of large-scale human interaction on the planet. Launched in September of 2009, the Oceansat-2 Ku-band scatterometer (OSCAT) is an excellent candidate for continuing the data time ser...

In the above-named article [ibid., vol. 51, no. 5, pp 1924-1934, April 2014] there are errors in Table I. The corrected table is published here.

Scatterometers provide frequent estimates of near-surface wind vectors over the Earth's oceans. However, in the polar oceans, the presence of sea ice in or near the measurement footprint can adversely affect scatterometer measurements, resulting in inaccurate wind estimates. Currently, such ice contamination is mitigated by discarding measurements...

Description A successor to the classic Artech House Microwave Remote Sensing series, this comprehensive and up-to-date resource previously published by University of Michigan Press provides you with theoretical models, system design and operation, and geoscientific applications of active and passive microwave remote sensing systems. To facilitate u...

A method, apparatus, and system to remotely acquire information from volumes in a snowpack and to analyze the information are disclosed. Electromagnetic energy is transmitted remotely to a region of interest in a snowpack and data about reflections are processed to determine reflection values for different volumes within the snowpack. The frequency...

Postlaunch calibration of satellite-borne scatterometers using backscatter data from natural land targets helps to maintain scatterometer accuracy. Due to its temporal stability, the dry-snow zone of the Greenland ice sheet has been proposed in previous studies as a calibration target. Using QuikSCAT data, this letter examines the backscatter prope...

The electromagnetic spectrum is a valued shared resource. Its scientific use allows us to learn about our Universe, measure and monitor our planet, and communicate scientific data. The use of the spectrum is managed by national, regional and global regulatory frameworks. There are increasing demands for new or extended allocations due to vast techn...

We have collected time series data of short oceanic waves as a part of the International Polar Year (IPY) 2007-2008. Using a shipboard laser wave slope (LAWAS) system operating at 900 nm, we have obtained wave slopes measurements up to 60 rad m-1 wave number. We have compared our in situ wave slopes with collocated and concurrent high-resolution up...

The electromagnetic spectrum is a valued shared resource. Its scientific use allows us to learn about our universe, measure and monitor our planet, and communicate scientific data. The use of the spectrum is managed by national, regional, and global regulatory frameworks. There are increasing demands for new or extended allocations because of vast...

The Marginal Ice Zone Ocean and Ice Observations and Processes EXperiment (MIZOPEX) aims to utilize unmanned aircraft in making repeated scientific observations of the surface water and sea-ice conditions during the melting period in the marginal ice zone of the Arctic Ocean. Unmanned aircraft from NASA will carry the sensors, a suite of instrument...

QuikSCAT was designed for ocean wind retrieval. However, its wind estimation performance is limited in rainy conditions. Several estimation techniques have been proposed: wind-only (WO), simultaneous wind and rain (SWR), and rain-only, which are appropriate for different levels of rain contamination. To exploit the strengths of each estimation meth...

In 2008, the Canadian Space Agency sponsored the Radarsat Hurricane Applications Project (RHAP), for researching new developments in the application of Radarsat-1 synthetic aperture radar (SAR) data and innovative mapping approaches to better understand the dynamics of tropical cyclone genesis, morphology, and movement. Although tropical cyclones c...

In final form 29 April 2012 ©2013 American Meteorological Society Sea surface imprints of 83 hurricanes show features such as eye structure, mesovortices, rainbands, and arc clouds, as well as rarities such as high winds within an eye. E ver since the launch of the first generation of meteorological satellites in the 1960s, Atlantic tropical cyclon...

Regional warming around West Antarctica, including the Antarctic Peninsula, is related to the retreat of glaciers that has resulted in significant ice mass loss in recent decades (De Angelis and Skvarca, 2003). Large icebergs (> 18.5 km long) originating from ice shelves in the Ross and Weddell Seas (Scambos et al., 2000) are attributed primarily t...

Long-term trends in Arctic sea ice are of particular interest in studies of global temperature, climate change, and industrial application. This paper analyzes intra-annual and interannual trends in Ku-band backscatter over first-year (FY) and multiyear (MY) sea ice to develop a new sea-ice-type classification method. Histograms of backscatter are...

Persistent katabatic winds form widely distributed localized areas of near-zero net surface accumulation on the East Antarctic ice sheet (EAIS) plateau. These areas have been called 'glaze' surfaces due to their polished appearance. They are typically 2–200 km2 in area and are found on leeward slopes of ice-sheet undulations and megadunes. Adjacent...

The 2010 Deepwater Horizon oil spill in the Gulf of Mexico covered a sufficiently large area to be observed by the European Space Agency Advanced Scatterometer (ASCAT) on MetOp-A. In this paper, ASCAT data and numerically computed winds from the European Centre for Medium-Range Weather Forecasts (ECMWF) are used to map the spatial extent of oil on...

In this study, we analyze 83 synthetic aperture radar (SAR) images including 73 from RADARSAT-1 and 10 from ENVISAT that contain tropical cyclone eye information. We also obtain ancillary tropical cyclone intensity information from NOAA National Hurricane Center and Japan Meteorological Agency. Based on this information, we generate tropical cyclon...

Two SeaWinds radar scatterometers operated in tandem for 9 months in 2003, enabling resolution of the diurnal cycle in Greenland. This dataset provides unprecedented temporal resolution for Ku-band scattering observations of snow and ice melt conditions. As a step towards improved radar-based melt intensity estimation, a simple Markov melt–thaw mod...

Recent accelerated mass loss from the Greenland ice sheet moderated by increased Arctic precipitation highlights the importance of a comprehensive understanding of the mechanisms controlling mass balance. Knowledge of the spatiotemporal variability of snow accumulation is critical to accurately quantify mass balance, yet the details are poorly unde...

Operational SeaWinds on QuikSCAT data can be enhanced to yield a 2.5 km ultra-high resolution (UHR) wind product, which can be used to help estimate tropical cyclone (TC) characteristics such as TC center and wind radii. This paper provides the results of two studies in which the QuikSCAT UHR wind product's effectiveness in estimating these TC char...

In the summer 2009 NASA Characterization of Arctic Sea Ice Experiment (CASIE09), the microASAR, a small LFM-CW SAR, was operated on the NASA Sierra unmanned aerial system (UAS). An overview of the microASAR and its role in CASIE09 are described in [1, 2]. While the limitations in the motion measurements stored with the microASAR data during the CAS...

This paper approaches wind field estimation from scatterometer measurements as the inversion of a noisy nonlinear sampling operation. The forward sampling model is presented and made discrete for practical purposes. Generally, the wind estimation problem is ill-posed at high resolution, which means that there are more parameters to estimate than me...

Although originally designed solely for wind retrieval, the QuikSCAT scatterometer has proved to be a useful tool for rain estimation as well. Resolution enhancement algorithms designed for QuikSCAT allow for ultra-high-resolution (UHR) (2.5 km) simultaneous wind and rain (SWR) retrieval. The principle advantage of UHR SWR estimation is that compar...

This paper approaches scatterometer image reconstruction as the inversion of a discrete noisy aperture-filtered sampling operation. Aperture-filtered sampling is presented and contrasted with conventional and irregular sampling. Discrete reconstruction from noise-free aperture-filtered samples is investigated and contrasted with conventional contin...

Knowledge of iceberg locations is important for safety reasons as well as for understanding many geophysical and biological processes. Originally designed to measure wind speed and direction over the ocean, SeaWinds is a microwave scatterometer that operates at 13.4GHz (Ku-band) on the QuikSCAT satellite. Radar measurements from SeaWinds are collec...

This paper describes the digital receiver for the microASAR, a small, powerful, LFM-CW SAR. The digital receiver uses a high-speed ADC providing three key benefits; namely: 1) the de-chirped signal can be at an arbitrary intermediate frequency (IF), enabling better RF filtering; 2) quantization noise can be reduced via digital filtering; and 3) the...

This paper compares the peak SNR and the point target impulse response function of stripmap SAR data processed with the well-known Omega-k algorithm and ideal matched filtering. The impulse response function resulting from Omega-k is distorted and stretched in azimuth compared to a matched filter. The distortion depends on the amount of frequency s...

The damping effects of oil on capillary ocean waves alter the backscattered power of radar measurements made by remote-sensing instruments such as scatterometers. Numerically computed vector winds are input to a wind geophysical model function (GMF) to determine the expected backscatter from the ocean surface uncontaminated by surface oil. Large di...

The MicroASAR and SlimSAR are small, low-cost, synthetic aperture radar (SAR) systems that represent a new advancement in high-performance SAR. ARTEMIS, Inc. and Brigham Young University have employed a unique design methodology that exploits previous developments in designing the SlimSAR to be smaller, lighter, and more flexible while consuming le...

Polar sea ice extent is an important input to global climate models and is considered to be a sensitive indicator of climate change. Spaceborne scatterometers such as the SeaWinds scatterometer on the QuikSCAT satellite have long been used to monitor sea ice extent due to their relatively low sensitivity to atmospheric effects. The QuikSCAT satelli...

The SeaWinds scatterometers aboard QuikSCAT and ADEOS II (Midori-2) provide normal-ized radar cross section (σ o) measurements of the Earth's surface at unprecedented coverage and resolution. While originally designed for wind observation, scatterometers have proven useful in a variety of land and ice studies. To further improve the utility of the...

Scatterometers have been launched primarily to measure ocean winds. The value of scatterometer data is increased by application of the SIR (Scatterometer Image Reconstruction) algorithm. The SIR algorithm enhances the effective resolution of the scatterometer data to support its use for other studies. SIR has been used successfully on several scatt...

During the summer of 2009, the Characterization of Arctic Sea Ice Experiment 2009 (CASIE-09) operated a small, unmanned aircraft system (UAS) over the Arctic Ocean for a number of long-distance flights from Svalbard Island. In addition to other instruments, the UAS carried a small C-band synthetic aperture radar (SAR) known as MicroASAR to image se...

The QuikSCAT scatterometer infers wind vectors over the ocean using measurements of the surface backscatter. During rain events the QuikSCAT observations are subject to rain contamination. Three separate estimators have been developed: wind-only, simultaneous wind and rain, and rain-only, which account for rain contamination in varying degrees. Thi...

The ASCAT scatterometer measures the backscatter from the ocean surface with which it infers the near-surface wind vector. When rain is present in the observation area the windinduced backscatter is modified by the rain. This paper uses co-located observations from TRMM PR to model the effects of rain on the ASCAT observed backscatter. Two model ty...

From 1999 to 2009, the SeaWinds scatterometer has been used to detect and track large Antarctic icebergs on a daily basis. Here, we develop an automated estimation algorithm to supplement iceberg position reports with estimates of the iceberg's major axis length, minor axis length, and angle of orientation. A maximum-likelihood objective function t...

This paper considers sampling and reconstruction theory with application to scatterometer image reconstruction. Backscatter imaging is approached as the inversion of a noisy aperture-filtered sampling operation. A reconstruction estimator based on maximum a posteriori probability (MAP) estimation is proposed to recover the conventional samples from...

The MicroASAR is a flexible, robust SAR system built on the successful legacy of the BYU μSAR. It is a compact LFM-CW SAR system designed for low-power operation on small, manned aircraft or UAS. The NASA SIERRA UAS was designed to test new instruments and support flight experiments. NASA used the MicroASAR on the SIERRA during a science field camp...

NuSAR (Naval Research Laboratory Unmanned Synthetic Aperture Radar) is a sensor developed under the ONRfunded FEATHAR (Fusion, Exploitation, Algorithms, and Targeting for High-Altitude Reconnaissance) program. FEATHAR is being directed and executed by the Naval Research Laboratory (NRL) in conjunction with the Space Dynamics Laboratory (SDL). FEATH...

The MicroASAR is a flexible, robust SAR system built on the successful legacy of the BYU ìSAR. It is a compact LFM-CW SAR system designed for low-power operation on small, manned aircraft or UAS. The NASA SIERRA UAS was designed to test new instruments and support flight experiments. NASA used the MicroASAR on the SIERRA during a science field cam...

Team members from NASA Ames Research Center developed a mission planning tool using Google Earth to support mission planning and monitoring during the Characterization of Sea Ice (CASIE) 2009 Mission to Svalbard, Norway. The tool allowed both deployed and non-deployed team members to view near-real time satellite imagery, ancillary information and...

In addition to record decreases in summer ice extent, the Arctic Ocean has also experienced extensive loss of the oldest, thickest sea ice types. The significance of this loss on overall sea ice mass and on the stability of the ice cover depends on how the thickness and physical properties of these older ice types vary with age, and on the degree t...

This paper presents a method whereby the range resolution of multi-frequency-band SAR systems can be enhanced. If multiple signals are coherent and cover disjoint frequency bands, they can be combined into a single signal which can be processed using slightly modified SAR processing algorithms, resulting in an image with a range resolution enhanced...

The SeaWinds scatterometer was originally designed to measure wind vectors over the ocean by exploiting the relationship between wind-induced surface roughening and the normalized radar backscatter cross section. Rain can degrade scatterometer wind estimation; however, the simultaneous wind/rain (SWR) algorithm was developed to enable SeaWinds to s...

Post processing reconstruction and resolution enhancement algorithms can be applied to Cassini Titan Radar Mapper data to improve the image resolution for scatterometermode imagery. Reconstruction algorithms can also yield enhanced resolution images when multiple passes are combined. This paper briefly describes the application of the AVE and the S...

Although QuikSCAT was originally designed to measure winds at a resolution of 25 km, higher resolution wind and rain products have been developed. The 2.5 km ultra high resolution (UHR) products allow QuikSCAT data to be used for applications involving rain, meso-scale phenomena, and in coastal applications. This paper overviews and unifies the var...

In 2002, a National Oceanographic Partnership Program project was initiated with the ambitious objective of maximizing the use of currently and soonto- be-available satellite ocean surface vector wind (OSVW) data, such as NASA's QuikSCAT scatterometer, in the operational weather forecasting and warning environment. This effort brought together peop...

The flight testing phase is vital in the development of an airborne SAR system, but can be time consuming and expensive, especially for UAS based systems. As part of a SAR design methodology, we are using a small, manned aircraft as a surrogate for UASs and other platforms. Prototypes of new systems can be easily installed on the testbed in order t...

The QuikSCAT scatterometer is used to accurately retrieve winds over the ocean at both high (2.5 km) and low (25 km) resolutions. In near-coastal regions, land contamination of measurements results in inaccurate wind estimates using current techniques. Here, we show that identifying land-contaminated measurements allows wind retrieval to be accurat...