cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.48577/jpl.af5bsx
title: Oil Spill Response-Oriented Information Products Derived from a Rapid-Repeat Time-Series of SAR Images

description: New quantitative and semi-automatable methods for analyzing oil slick evolution using a time series of L-band Synthetic Aperture Radar (SAR) images with short repeat time are developed and explored. In this study, two methods that are complementary in terms of identifying temporal changes within an oil slick are presented. The two methods reflect two ways of evaluating the oil slicks. The first method identifies regions within the slick that show persistently high damping ratio (the contrast between clean sea and oil intensity), using higher damping values as a proxy for increasing oil thickness. This method also weights the age of the scenes as the algorithm incorporates new images. The second method outputs the short-term drift pattern and the changes in the damping ratios and copolarization ratios between two scenes, proxies for thickness and emulsification. Both methods can aid in identifying regions of high priority for oil recovery. Due to the simplicity of the methods, they can be adapted to time series data from different types of sensors, e.g., optical and SAR imagery. The methods are demonstrated on three L-band Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) time series acquired in November 2016 over a persistent seep in the Mississippi Canyon block 20 (MC-20) of the Gulf of Mexico. The results of the two methods clearly show the movement and the weathering of the oil as a function of both time and location.
DOI: 10.48577/jpl.zarhsj
title: Goldstone Apple Valley Radio Telescope Observations of 2012 Solar Eclipse: A Multi-wavelength study of cm-l Gyroresonance Emission from Active Regions

description: Goldstone Apple Valley Radio Telescope (GAVRT) is a science education partnership among NASA, the Jet Propulsion Laboratory (JPL), and the Lewis Center for Educational Research (LCER), offering unique opportunities for K -12 students and their teachers. The GAVRT program operates a 34-m radio telescope with a wide-band, low noise receiver, which is tunable in four independent dual-polarization bands from 3 to 14 GHz. The annular eclipse of the Sun on 2012 May 20 was observed by GAVRT as part of education outreach. In this paper we present the results of this eclipse data and discuss the multi-wavelength derived strip scan brightness distribution across three active regions. We derive the source brightness temperatures and angular sizes as function frequency and interpret the results in terms of gyroresonance mechanism. We show examples of the increasing brightness and widening of source size (isogauss surface) with wavelength as evidence for gyroresonance absorption layers of diverging magnetic field geometry above solar surface. We present an example how the derived frequency – brightness temperature relationship is translated to a magnetic field – brightness temperature relationship under the frame-work of gyroresonance absorption. Our results demonstrate the usefulness of GAVRT bands as excellent probe to study the layers of the corona above the active regions (sun spots), in particular the prevalence of the gyroresonance mechanism.
DOI: 10.48577/jpl.13chws
title: Internal Kinematics of the Slumgullion Landslide (USA) from High-resolution UAVSAR InSAR Data

description: Landslides represent one of the most damaging natural hazards and often lead to unexpected casualties and property damage. They also continually modify our natural environment and landscapes. Knowledge of landslide systems is largely restricted by the stochastic nature, subjective interpretation and infrequent or spatially sparse surveying of landslides. Characterized by persistent daily movements of a couple of centimeters over multi-centennial timescales and a long narrow shape as long as ~4 km, the Slumgullion landslide in Colorado, USA represents an ideal natural laboratory to study slow-moving landslides. Here we demonstrate the capability of the highly accurate, spatially continuous airborne Synthetic Aperture Radar (SAR) system of Uninhabited Aerial Vehicle SAR (UAVSAR) to characterize the kinematic details of internal deformation of the Slumgullion landslide using SAR interferometry (InSAR). We develop a phase-based approach to automatically extract the boundaries of the geological structures without unwrapping. Taking advantage of the high-resolution UAVSAR interferograms, a comparison with historic observations in 1991 reveals an advance of ~40 m and internal faulting of the frontal toe. A comparison of the InSAR data pairs collected during the 2011-2018 observing period suggests that the landslide moved the fastest in 2015 and the slowest in 2018, consistent with multi-annual variations in precipitation. The UAVSAR data also resolve an internal minislide (100 by 70 m), which moves more southerly than the main body at 5 mm/day in the lower part of the landslide. A Light Detection and Ranging (LiDAR) Digital Elevation Model (DEM) shows that the minislide is associated with the opening of a 30 by 10 m pull-apart basin and bounding strike-slip faults. These extensional structures, nearby incised streams, and steepened local slopes helped establish the kinematic environment for the formation of the secondary minislide. The disparity between the UAVSAR InSAR-derived horizontal moving directions and the LiDAR DEM-derived slope aspects suggest that while the surface topography governs the first-order orientation, the local kinematics is also subject to the variable nature of heterogeneous landslide materials and the irregular basal bedrock surface. Our study demonstrates that the freely available, high-resolution UAVSAR data, have great potential for characterizing landslide kinematics and other small-scale geological and geomorphological processes.
DOI: 10.48577/jpl.hq9vot
title: Investigation of Venus Cloud Aerosol and Gas Composition including Potential Biogenic Materials via an Aerosol-Sampling Instrument Package

description: A lightweight, low-power instrument package to measure, in-situ, both (1) the local gaseous environment and (2) the composition and microphysical properties of attendant Venusian aerosols. This Aerosol-Sampling Instrument Package (ASIP) would be used to explore cloud chemical and possibly biotic processes on future aerial missions such as multi-week balloon missions and on short-duration (&lt;1 hour) probes on Venus and potentially on other cloudy worlds such as Titan, the Ice Giants, and Saturn. A QITMS (Madzunkov and Nikolić, J. Am. Soc. MassSpectr., 25, 1841 - 1852, 2014) fed alternately by (1) anaerosol separator that injects only aerosols into a vaporizer and mass spectrometer, and (2) the pureaerosol-filtered atmosphere, achieves the compositional measurements. Aerosols vaporized &lt; 600 oC are measured over atomic mass ranges from 2 to 300 AMU at &lt;0.02 AMU resolution, sufficient to measure trace materials, their isotopic ratios and potential biogenic materials embedded within H2SO4 aerosols, to better than 20% in &lt; 300 sec for H2SO4 -46 relative abundances of 2 x 10-9. An attached lightweight, compact nephelometer/particle-counter determines the number density and particle sizes of the sampled aerosols.
DOI: 10.48577/jpl.izoahj
title: A Quantitative Framework to Inform Cloud Data System Architecture and Services Requirements Based on User Needs and Expected Demand

description: The NASA open data policy and the increases in data volume from recent and future missions have resulted in a need to re-evaluate data archive information systems and services. For example, the Surface Water Ocean Topography mission (SWOT) will produce ~15 TB of data every day that needs to be freely and openly accessible through the NASA Physical Oceanography Distribute Active Archive Center (PO.DAAC). Because of the computational, and distribution challenges associated with making such volumes of Earth Observation data publicly available, the NASA Earth Science Data Information System (ESDIS) is moving their archive systems, like PO.DAAC, to the cloud. To facilitate this migration, system requirements need to accommodate expected use. As such, the objective of this study was to assesses expected user needs and develop a quantitative framework that can be traced to requirements for the cloud-based data archive system architecture and services that enable data discovery, access and utility. We used a two-tier data gathering method that included a short survey of potential users (identified at professional meetings and community listservs) and in-depth interviews. The survey provided a means for scaling findings from the in-depth interviews to a more representative sample, thus enabling assessment of expected impact to various user communities for different services that could be provided. This framework enables traceability for setting priorities data services development to requirements for a cloud-based data archive system and services that enable data discovery, access and utility.
DOI: 10.48577/jpl.a3cahb
title: TESS Hunt for Young and Maturing Exoplanets (THYME) III: a two-planet system in the 400 Myr Ursa Major Group

description: Exoplanets can evolve significantly between birth and maturity as their atmospheres, orbits, and structures are shaped by their environment. Young planets (􏰀1 Gyr) offer the opportunity to probe these sculpting processes. However, most of the known young planets orbit prohibitively faint stars. We present the discovery of two planets transiting HD 63433 (TOI 1726, TIC 130181866), a young Sun-like (M∗ = 0.99 ± 0.03) star. Through kinematics, lithium abundance, and rotation, we confirm that HD 63433 is a member of the Ursa Major moving group (τ = 414 ± 23 Myr). Based on the TESS light curve and updated stellar parameters, the planet radii are 2.15 ± 0.10R⊕ and 2.67 ± 0.12R⊕, the orbital periods are 7.11 and 20.55days, and the orbital eccentricities are lower than abut 0.2. Using HARPS-N velocities, we measure the Rossiter-McLaughlin signal of the inner planet, demonstrating the orbit is prograde. Since the host star is bright (V=6.9), both planets are amenable to transmission spectroscopy, radial velocity measurements of their masses, and more precise determination of the stellar obliquity. This system is therefore poised to play an important role in our understanding of planetary system evolution in the first billion years after formation.
DOI: 10.48577/jpl.sfamb1
title: GW Ori: Interactions Between a Triple-star System and its Circumtriple Disk in Action

description: GW Ori is a hierarchical triple system with a rare circumtriple disk. We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of 1.3 mm dust continuum and 12CO J = 2􀀀1 molecular gas emission of the disk. For the first time, we identify three dust rings in the GW Ori disk at 46, 188, and 338 AU, with estimated dust mass of 74, 168, and 245 Earth masses, respectively. To our knowledge, its outermost ring is the largest dust ring ever found in protoplanetary disks. We use visibility modelling of dust continuum to show that the disk has misaligned parts, and the innermost dust ring is eccentric. The disk misalignment is also suggested by the CO kinematics. We interpret these substructures as evidence of ongoing dynamical interactions between the triple stars and the circumtriple disk.
DOI: 10.48577/jpl.aviuqx
title: A Multi-model Evaluation of the Water Vapor Budget in Atmospheric Rivers

description: Atmospheric rivers (ARs) are narrow regions of strong horizontal water vapor transport that 27 play important roles in the global water cycle, weather, and hydrology. Motivated by challenges in 28 simulating ARs with state-of-the-art global models, this paper diagnoses model errors with a focus on 29 relative contributions of moisture convergence, evaporation, and precipitation to AR column-integrated 30 water vapor (IWV) budget. 31 Using 20-year simulations by 24 global weather/climate models, budget terms are calculated for 32 four AR sectors: post-frontal, frontal, pre-frontal, and pre-AR, with biases assessed against two 33 reanalysis products. The results indicate that each sector is unique in terms of the dominant water vapor 34 balance, and that the terms exhibiting the largest inter-model spread are the same terms dominating the 35 water vapor balance in each sector. Overall, simulated bulk AR characteristics (e.g., geometry, 36 frequency, intensity) are more sensitive to biases in IVT convergence and IWV tendency than to biases 37 in evaporation and precipitation, although evaporation/precipitation biases do affect key AR bulk 38 characteristics in selected sectors. The large inter-model spread (particularly for precipitation) and, in 39 certain cases, discrepancies between the reanalysis references themselves (particularly for precipitation 40 types), highlight the need for observational efforts that target better constraining AR processes in 41 weather/climate models and reanalyses.
DOI: 10.48577/jpl.h5rsgf
title: Ice Giant Seismology: Prospecting for Normal Modes

description: The properties of ice-giant normal mode oscillations, including their periods, spatial structure, stratospheric amplitudes, and relative influence on the external gravity field, are surveyed for the purpose of formulating the best strategy for their eventual detection. Measurement requirements for detecting a normal mode’s periodic pressure and temperature variations, including a possible stratospheric signal, and its effect on the external gravity field, are discussed in terms of its assumed radial velocity amplitude at the 1-bar pressure level. It is found that for reasonable amplitudes, detection of the pressure and temperature variations of ice-giant normal modes presents an extraordinary technical challenge. The prospects for detecting their gravitational influence on an orbiting spacecraft are much better, with requirements that lie within the range of current technology.
DOI: 10.48577/jpl.10kzdc
title: Retrieved wind speed from the Orbiting Carbon Observatory-2

description: Satellite measurements of surface wind speed over the ocean inform a wide variety of scientific pursuits. While both activeand passive microwave sensors are traditionally used to detect surface wind speed over water surfaces, measurements ofreflected sunlight in the near-infrared made by the Orbiting Carbon Observatory-2 (OCO-2) are also sensitive to the wind speed. In this work, retrieved wind speeds from OCO-2 glint measurements are validated against the Advanced MicrowaveScanning Radiometer-2 (AMSR2). Both sensors are in the international Afternoon Constellation, allowing for a large numberof co-located observations. Several different OCO-2 retrieval algorithm modifications are tested, with the most successful beinga single-band Cox-Munk-only model. Using this, we find excellent agreement between the two sensors, with OCO-2 having asmall mean low bias against AMSR2 of -0.22 m/s, an RMSD of 0.75 m/s, and a correlation coefficient of 0.94. Although OCO-2 is restricted to clear-sky measurements, potential benefits of its higher spatial resolution relative to microwave instrumentsinclude the study of coastal wind processes, which may be able to inform certain economic sectors.
DOI: 10.48577/jpl.9v9qn1
title: Efficient multi-scale Gaussian process regression for massive remote sensing data with satGP v0.1.2

description: Abstract. Satellite remote sensing provides a global view to processes on Earth that has unique benefits compared to making measurements on the ground, such as global coverage and enormous data volume. The typical downsides are spatial and temporal gaps and potentially low data quality. Meaningful statistical inference from such data requires overcoming these problems and developing efficient and robust computational tools. We design and implement a computationally efficient multi- scale Gaussian process (GP) software package, satGP, geared towards remote sensing applications. The software is able to handle problems of enormous sizes and to compute marginals and sample from the random field conditioning on at least hundreds of millions of observations. This is achieved by optimizing the computation by e.g. randomization and splitting the problem into parallel local subproblems which aggressively discard uninformative data. We describe the mean function of the Gaussian process by approximating marginals of a Markov random field (MRF). Variability around the mean is modeled with a multi-scale covariance kernel, which consist of Matérn, exponential, and periodic components. We also demonstrate how winds can be used to inform covariances locally. The covariance kernel parameters are learned by calculating an approximate marginal maximum likelihood estimate, and the validity of both the multi-scale approach and the method used to learn the kernel parameters is verified in synthetic experiments. We apply these techniques to a moderate size ozone data set produced by an atmospheric chemistry model, and to the very large number of observations retrieved from the Orbiting Carbon Observatory 2 (OCO-2) satellite.
DOI: 10.48577/jpl.8a7sjt
title: Far-UVC light as a new tool to reduce microbial burden during spacecraft assembly

description: Aims: This work aims to investigate far-UVC light at 222 nm as a new microbial reduction tool for planetary protection purposes which could potentially be integrated into the spacecraft assembly process. The major advantage of far-UVC (222 nm) compared to traditional germicidal UVC (254 nm) is the potential for application throughout the spacecraft assembly process in the presence of humans. Testing the efficacy of 222-nm light at inactivating hardy bacterial cells and spores isolated from spacecraft and associated surfaces is a necessary step to evaluate this technology. Methods and Results: We assessed survival of Bacillus pumilus SAFR-032 and Acinetobacter radioresistens 50v1 exposed to 222-nm light on proxy spacecraft surfaces simulated by drying the bacteria on aluminum coupons. The survival fraction of both bacteria followed a single stage decay function up to 60 mJ/cm2, revealing similar susceptibility of both species to 222-nm light, which was independent of the fluence rate. Conclusions: Irradiation with far-UVC light at 222 nm is an effective method to decontaminate the proxy spacecraft materials tested in this study. Significance and Impact of Study: Microbial burden of spacecraft hardware is closely monitored for planetary protection purposes. Current methods of reducing surface microbial contamination such as wiping with a solvent or exposure to vapor hydrogen peroxide are time consuming, disruptive to the assembly process, and susceptible to recontamination. Exposing spacecraft surfaces to far-UVC light is a promising technique for microbial reduction during the assembly process with minimal increase in engineering scope of work.
DOI: 10.48577/jpl.9mwvzp
title: LOCUS: A Multi-Sensor Lidar-Centric Solution for High-Precision Odometry and 3D Mapping in Real-Time

description: Achieving consistent lidar odometry in perceptually-degraded environments is a challenging problem. In these settings, self-similar areas, noisy sensor returns, high-rate rotations and large accelerations can greatly compromise the accuracy of the estimated odometry. While integrating additional sensor readings could help address these challenges, potential sensor failures must be robustly handled to not compromise the overall outcome of the mission. In this work, we present a lidar odometry system built for accurate and robust operation in extreme environments. The proposed system provides a failure-safe sensor integration module to flexibly include additional IMU and odometry measurements into lidar odometry. It is designed to be adaptable to different robotic platforms with diverse sensor inputs and computational capabilities to optimize real-time operation under challenging conditions. The system further provides a series of environment adaptation controls, including a flat ground assumption feature for operation in human-made buildings. We evaluate the performance of the proposed system against state-of-the-art techniques and discuss the enhancements achieved in localization accuracy and robustness to sensor failures. We also demonstrate real-time operation two different robots involved in exploration of the Satsop nuclear power plant, WA where the proposed system was a part of the CoSTAR team's solution that won first place at the Urban Circuit of the DARPA Subterranean Challenge.
DOI: 10.48577/jpl.erbazw
title: Aerosol profiling using radiometric and polarimetric spectral measurements in the O2 near infrared bands: Estimation of information content and measurement uncertainties

description: Characterization of aerosol vertical distribution in the planetary boundary layer (PBL) using passive remote sensing requires advances in the current state of the art. To quantify the performance of various passive sensor designs within a common framework we developed an aerosol climatology of the Los Angeles basin and applied observing system simulation experiments (OSSEs) to estimate the information content retrievable from a variety of sensors measuring reflected near-infrared solar radiation. In addition to simulating current and planned satellite sensors, we also characterize the sensitivity of the California Laboratory for Atmospheric Remote Sensing – Fourier Transform Spectrometer (CLARS-FTS), located at Mt Wilson (1.67 km above sea level), which is utilized in this work as a testbed for aerosol profiling remote sensing. We estimate the impacts of spectral coverage, radiance and polarization, spectral resolution, signal to noise ratio (SNR), and number of viewing angles on the information content and retrieval uncertainties of aerosol profiles in the PBL. We found that by adding high spectral resolution (full-width half-maximum of 3 cm1 or better), polarimetric measurements with a SNR of at least 212 to radiance measurements with SNR of 300 for both O2 A and 1∆ bands, the degrees of freedom for signal (DOFS) of a single CLARS-FTS measurement is raised from 2.1 to 2.8. This improvement is sufficient to simultaneously quantify three key parameters: aerosol optical depth, aerosol peak height, and aerosol layer thickness in the PBL. Current satellite-borne instruments (OCO-2, OCO-3, TEMPO, TROPOMI, and EPIC) and planned instruments (TEMPO, MicroCarb, SPEXone, and MAIA), individually provide a DOFS  2.25, which is insufficient to simultaneously quantify all three aerosol profiling parameters in the PBL. Joint radiometric and polarimetric measurements of the O2 A and B bands with 3 cm1 spectral resolution, SNR of 500 for radiance and 353 for polarization, acquired at three viewing angles, can provide sufficient sensitivity to retrieve the three aerosol parameters simultaneously. The inclusion of high spectral resolution radiometric and polarimetric measurements reduces the required number of viewing angles, which is advantageous when the multiangular data are acquired with a pointable instrument. In this case a larger number of viewing angles reduces the spatial coverage that can be achieved for a given target.
DOI: 10.48577/jpl.rcncii
title: Ocean mass, sterodynamic effects and vertical land motion largely explain US coast relative sea level rise

description: Regional sea-level changes are caused by several physical processes that vary both in space and time. As a result of these processes, large regional departures from the long-term rate of global mean sea-level rise can occur. Identifying and understanding these processes at particular locations is the first step toward generating reliable projections and assisting in improved decision making. Here we quantify to what degree contemporary ocean mass change, sterodynamic effects, and vertical land motion influence sea-level rise observed by tide-gauge locations around the contiguous U.S. from 1993 to 2018. We are able to explain tide gauge-observed relative sea-level trends at 47 of 55 sampled locations. Locations where we cannot explain observed trends are potentially indicative of shortcomings in our coastal sea-level observational network or estimates of uncertainty.