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At least 379 records · Page 21
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

CHESS 2025: Field-collected vegetation attributes and site photos

This dataset represents field observations of vegetation samples collected as part of the Colorado Headwaters Ecological Spectroscopy Study (CHESS) during June and July of 2025. Samples were collected in the field using tablet computers and digital forms, with target data differing by sample type (individual trees, individual shrubs, or 1-meter square plots of meadow and subshrub vegetation). Field samples were collected within 72 hours of airborne data collection using the National Ecological Observatory Network’s Aerial Observation Platform (NEON AOP). The NEON AOP collected waveform LiDAR (Light Detection and Ranging) and imaging spectrometer data in 426 spectral bands from the visible to shortwave infrared. Remote sensing data for the project is available on ESS-DIVE (DOI and citation to be added upon publication). Field data collected included canopy height and per-species horizontal proportional cover for meadow plots, species identity and height information for shrubs, as well as species identity, height, diameter at breast height, and health assessment information for trees. Photos of the focal site and surrounding landscape were taken for all sampling sites and are included in this archive. Green leaves or needles were collected for plant trait and foliar chemistry analysis. This data is archived separately (DOI and citation to be added upon publication). High-precision geospatial data for each sample (crown perimeter polygons for trees and shrubs, plot boundaries for meadow plots) is available here (Henderson et al., 2026). Field and remote sensing protocols largely followed those of a previous field and airborne imaging campaign performed in 2018 (described in Chadwick et al. 2020). Field data from the 2018 campaign can be found here (Chadwick et al., 2020 doi:10.15485/1618130). Because different field measurements were taken for meadow, shrub, and tree sites, data from these three sample types are archived as separate tables (chess_meadow_site_cleaned.csv, chess_shrub_site_cleaned.csv, chess_tree_site_cleaned.csv). Meadow proportional cover data is stored in a separate table (chess_meadow_cover_cleaned.csv). Taxonomy was treated identically between sample types, and the dataset shares a common set of voucher specimens (chess_voucher_IDs_cleaned.csv), as well as a single species list (chess_species_list_cleaned.csv). All taxonomic determinations were performed to the species level, and adhere to the Global Biodiversity Information Facility (GBIF) backbone taxonomy as of January 10th, 2026 (GBIF Secretariat 2023). CHESS Project Description: The Colorado Headwaters Ecological Spectroscopy Study (CHESS) comprised a multi-week airborne remote sensing and field observation campaign in the Upper Gunnison Basin, Colorado, conducted in June and July of 2025. Airborne remote sensing was conducted by the National Ecological Observatory Network Airborne Observation Platform (NEON AOP), concurrent with a field campaign run by the Rocky Mountain Biological Laboratory (RMBL), the Lawrence Berkeley National Laboratory (LBNL) and SLAC National Accelerator Laboratory Watershed Function Science Focus Area (SFA), and NASA-JPL (Jet Propulsion Laboratory) Earth Surface Mineral Dust Source Investigation (EMIT) program. Between June 10 and July 18, 2025, the NEON AOP flight team collected high-resolution aerial imaging spectroscopy and Light Detection and Ranging (LiDAR) data over three domains: the Upper East River (CRBU), Almont Triangle (ALMO), and the Upper Taylor Basin (UPTA). In coordination with the flights, a field campaign acquired ground-truth observations, including observations of vegetation composition, foliar traits, forest demography, and subsurface properties in 18 core sampling areas within the domains. Additional surface water observations were taken at over 380 point locations. All CHESS campaign datasets can be found within the CHESS ESS-DIVE data portal: https://data.ess-dive.lbl.gov/portals/chess. Funding Acknowledgment: Field and remote-sensing data acquisition was performed under a grant from the National Aeronautics and Space Administration (80NSSC24K1005). This work was also supported by the Watershed Function Science Focus Area at Lawrence Berkeley National Laboratory funded by the US Department of Energy, Office of Science, Biological and Environmental Research under Contract No. DE-AC02-05CH11231.

2018 NEON and 2025 CHESS Campaigns↗
NASA NTRS1975

Comparison of inferred and observed interplanetary magnetic field polarities, 1970-1972

The inferred polarity (toward or away from the sun) of the interplanetary magnetic field at earth using polar observations of the geomagnetic field has been compared with spacecraft observations. A list published by Svalgaard (1974) of the inferred field polarities in the period from 1970 to 1972 is found to be correct on 82% of the days. A near real-time (same day) method of inferring the polarity of the interplanetary magnetic field using geomagnetic observations at Vostok and Thule is in use at the NOAA Space Environment Laboratory, Boulder, Colorado. During 1972, this method is found to be correct on 87% of the days. A list of 'well-defined' sector boundaries at earth from 1970 to 1972 is given.

Wilcox, J. M.↗
DOE OSTI2026

CHESS 2025: Crown polygons and extracted reflectance for field sampling sites

This dataset contains (1) crown polygons for each tree, meadow, and shrub site sampled in the 2025 Colorado Headwaters Ecological Spectroscopy Study (CHESS) campaign (in geojson format, .geojson) and (2) extracted reflectance, uncertainty, and shade estimates for each crown polygon from the 2018 National Ecological Observatory Network (NEON) and 2025 CHESS campaigns. (in CSV format, .csv). Additional metadata are provided in a data dictionary describing column names and definitions (dd.csv), and in a file-level metadata file (flmd.csv). Crown polygons were manually delineated for each site in the 2025 campaign using a combination of field-collected GPS data (doi:10.15485/3022418), RGB (red, green, blue) and false color reflectance mosaics (doi:10.15485/3013535), and LiDAR-derived (Light Detection and Ranging) canopy height (CHM) and digital surface (DSM) models (DOI and citation to be added upon publication). Where there was misalignment between the spectrometer- and LiDAR-derived data products, polygons prioritized alignment with the spectrometer-derived data products. Polygons were delineated conservatively to only select pixels representative of vegetation samples collected in the field. Crown polygons for 2018 are published at (doi:10.15485/1618130) and were developed using the same protocol. For each polygon, all pixels from all flightlines were extracted where the pixel centroid was contained within the polygon. For each pixel, we extracted the surface reflectance, uncertainty, and shade estimates. Details on the extracted datasets are available at (doi:10.15485/3013527, doi:10.15485/3013535). CHESS Project Description: The Colorado Headwaters Ecological Spectroscopy Study (CHESS) comprised a multi-week airborne remote sensing and field observation campaign in the Upper Gunnison Basin, Colorado, conducted in June and July of 2025. Airborne remote sensing was conducted by the National Ecological Observatory Network Airborne Observation Platform (NEON AOP), concurrent with a field campaign run by the Rocky Mountain Biological Laboratory (RMBL), the Lawrence Berkeley National Laboratory (LBNL) and SLAC National Accelerator Laboratory Watershed Function Science Focus Area (SFA), and NASA-JPL (Jet Propulsion Laboratory) Earth Surface Mineral Dust Source Investigation (EMIT) program. Between June 10 and July 18, 2025, the NEON AOP flight team collected high-resolution aerial imaging spectroscopy and Light Detection and Ranging (LiDAR) data over three domains: the Upper East River (CRBU), Almont Triangle (ALMO), and the Upper Taylor Basin (UPTA). In coordination with the flights, a field campaign acquired ground-truth observations, including observations of vegetation composition, foliar traits, forest demography, and subsurface properties in 18 core sampling areas within the domains. Additional surface water observations were taken at over 380 point locations. All CHESS campaign datasets can be found within the CHESS ESS-DIVE data portal: https://data.ess-dive.lbl.gov/portals/chess. Funding Acknowledgment: This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004) and was funded by EMIT Extended Mission Phase E Science.

2018 NEON and 2025 CHESS Campaigns↗
NASA NTRS1976

Interplanetary disturbances caused by the August 1972 solar flares as observed by Pioneer 9

Pioneer 9 plasma and field observations at 0.78 AU were used as the basis of the analysis of the dynamic behavior of the interplanetary medium during early August, 1972. The following investigations were carried out: (1) energy and mass estimates for the solar flares of Aug. 2, 4, and 7; (2) shock wave characteristics; and (3) a numerical simulation of the first two flare-generated disturbances on Aug. 2, 4, and 7.

Dryer, M.↗
NASA NTRS1980

On the search for an intrinsic magnetic field at Venus

Magnetic field observations obtained by the Pioneer Venus orbiter at low altitude are now available for two sets of orbits in the Venus wake. Data from these 130 orbits are examined for possible surface correlated features or any intrinsic magnetic moment. No surface correlated magnetic fields are observed, but the threshold for the detectability of such fields at Venus is about an order of magnitude greater than at the moon. A surface feature of 10 deg extent would have to create an anomaly of at least 5 gammas at 200 km to be detected in the Pioneer Venus data. Using measurements averaged in 72 10 x 10 deg bins, a planetary magnetic dipole moment of 0.87 + or - 3.00 x 10 to the 21st gauss-cu cm is obtained. Thus the upper limit of the present day Venus moment is less than 4 x 10 to the -5th of the terrestrial moment.

Russell, C. T.↗
NASA NTRS1976

Field-aligned currents observed by the Ogo 5 and Triad satellites

The Triad (at a height of 800 km) and Ogo 5 (in the high altitude magnetosphere) magnetic field observations have shown the existence of a field-aligned current system consisting of currents flowing in the polar cap boundary layer and those flowing in another layer located equatorward of the former. In the polar cap boundary layer (identified as the high-latitude boundary of the plasma sheet in the nightside magnetosphere), the current flows into the ionosphere on the morning side and away from the ionosphere on the afternoon side. In the lower-latitude layer, the current directions are reversed. The current in the polar cap boundary layer is considered as the primary field-aligned current system.

Sugiura, M.↗
NASA NTRS1971

A note on the effect of reflected solar radiation on airborne and ground measurements in the thermal infrared

The magnitude of thermal solar radiation reflected from water surfaces is considered. It is shown both theoretically and by field observation that, for instruments with small fields of view, the reflected thermal solar radiation can contribute significantly to the measured energy. Comparison of thermal scanner data taken from aircraft at a 16 deg azimuth angle from the mirror point of the sun over the open ocean with data taken at a 164 deg anzimuth angle from the mirror point of the sun at the same angle from nadir is indicative of a difference of 2.8 K in the equivalent black body radiation temperature. Observations taken from a surface vessel into sunglint 80 deg from nadir are indicative of an equivalent black body radiation temperature that is 34 K warmer than the temperature obtained at a similar nadir angle away from the sunglint.

Whitehead, V. S.↗
NASA NTRS1979

A new technique for measuring solar rotation

A new technique for measuring solar photospheric and subphotospheric rotation rates is described. The technique utilizes the standing-wave nature of the nonradial p-mode oscillations of the whole sun. Specifically, the technique is based upon the observed concentration of p-mode oscillatory power into well defined ridges in two-dimensional wavenumber-frequency power spectra. The frequencies of the ridges in the eastward- and westward-traveling portions of an individual spectrum are systematically shifted in opposite directions by a drift of the standing-wave pattern across the observing field of view. The magnitudes of these frequency shifts are related to the drift velocity and to the horizontal wavenumber in such a way that measurement of the observed frequency shifts in a spectrum yields the drift velocity for that observing run. By guiding on the solar limbs and observing the velocity field at disk center, the observed drift velocity obtained in this way is exactly the rotational velocity of the solar p-mode pattern, and of the solar gas itself.

Rhodes, E. J., Jr.↗
DOE OSTI2024

Observation and Reanalysis Derived Relationships Between Cloud and Land Surface Fluxes Across Cumulus and Stratiform Coupling Over the Southern Great Plains

Abstract Understanding interactions between low clouds and land surface fluxes is critical to comprehending Earth's energy balance, yet their relationships remain elusive, with discrepancies between observations and modeling. Leveraging long‐term field observations over the Southern Great Plains, this investigation revealed that cloud‐land interactions are closely connected to cloud‐land coupling regimes. Observational evidence supports a dual‐mode interaction: coupled stratiform clouds predominate in low sensible heat scenarios, while coupled cumulus clouds dominate in high sensible heat scenarios. Reanalysis data sets, MERRA‐2 and ERA‐5, obscure this dichotomy owing to a shortfall in representing boundary layer clouds, especially in capturing the initiation of coupled cumulus in high sensible heat scenarios. ERA‐5 demonstrates a relatively closer alignment with observational data, particularly in capturing relationships between cloud frequency and latent heat, markedly outperforming MERRA‐2. Our study underscores the necessity of distinguishing different cloud coupling regimes, essential to the understanding of their interactions for advancing land‐atmosphere interactions.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS1983

Ozone variations observed during the International Ozone Rocket Sonde Intercomparison

The International Ozone Rocket Sonde Intercomparison (IORI) conducted at Wallops Island during October 1979 provided a unique opportunity to observe ozone variations in great detail from several observing systems. The measurement period lasted 15 days during which time ozone observations were taken by ground-based, balloon, rocket, and satellite instruments. These data provided a unique opportunity for diagnosing regional stratospheric variability over a 2 week period. Examination of NMC analyses indicated that during this period the stratospheric polar vortex moved southeastward bringing air form high latitudes to Wallops Island above 10 mb. A concurrent change was observed in the upper stratosphere ozone fields observed by Nimbus-7 SBUV and in the ozone vertical distribution measured by the rocket soundings. In this study the satellite and rocket measurements are compared. The agreement is good, certainly within the errors of the measurements.

Hilsenrath, E.↗
NASA NTRS1983

The radial evolution of the solar wind, 1-10 AU

The interplanetary plasma and magnetic field observations from 1 to 10 AU are reviewed. Over this distance no clear reduction in average speed is seen. The range of wind speeds becomes smaller though high speed streams are still observed. The density, temperature and magnetic field profiles become dominated by the large values seen in the co-rotating interaction regions. The temperature falls more slowly than would be expected from a simple, adiabatic model. Co-rotating shocks appear beyond approximately 3 AU in Voyager data as opposed to beyond approximately 1.5 AU in the Pioneer data. Reverse shocks appear later than forward shocks; reverse shocks do not begin to appear until approximately 4 AU; reverse shocks appear to decay more rapidly than forward shocks. No clear effect due to interaction with the interstellar medium was seen in this radial range.

Gazis, P. R.↗
NASA NTRS2009

MESSENGER Observations of Magnetic Reconnection in Mercury's Magnetosphere

During MESSENGER'S second flyby of Mercury on October 6,2008, very intense reconnection was observed between the planet's magnetic field and a steady southward interplanetary magnetic field (IMF). The dawn magnetopause was threaded by a strong magnetic field normal to its surface, approx.14 nT, that implies a rate of reconnection approx.10 times the typical rate at Earth and a cross-magnetospheric electric potential drop of approx.30 kV. The highest magnetic field observed during this second flyby, approx.160 nT, was found at the core of a large dayside flux transfer event (FTE). This FTE is estimated to contain magnetic flux equal to approx.5% that of Mercury's magnetic tail or approximately one order of magnitude higher fraction of the tail flux than is typically found for FTEs at Earth. Plasmoid and traveling compression region (TCR) signatures were observed throughout MESSENGER'S traversal of Mercury's magnetotail with a repetition rate comparable to the Dungey cycle time of approx.2 min. The TCR signatures changed from south-north, indicating tailward motion, to north-south, indicating sunward motion, at a distance approx.2.6 RM (where RM is Mercury's radius) behind the terminator indicating that the near-Mercury magnetotail neutral line was crossed at that point. Overall, these new MESSENGER observations suggest that magnetic reconnection at the dayside magnetopause is very intense relative to what is found at Earth and other planets, while reconnection in Mercury's tail is similar to that in other planetary magnetospheres, but with a very short Dungey cycle time.

Slavin. James A.↗
NASA NTRS2019

Rapid Prediction of Installed Jet Noise from RANS

A new method of computing jet noise, called mSrc, was developed on the general principles of acoustic analogies. In the method, the problem of translating turbulent flow energy into acoustic energy at a far-field observer is broken into two parts, a calculation of acoustic source strengths and then their propagation. The acoustic sources are related to turbulent quantities in the jet plume in a robust manner. The propagation, which is more properly computed using a Green's function accounting for nonuniform speed of sound and solid surfaces, is instead modeled using commonly observed features of jet acoustic far field directivity, and by diffraction barrier theory for surfaces. The mSrc method does not require gradients of the predicted flow field, allowing it to make use of robust unstructured RANS CFD methods, including embedded boundary codes. Such codes do not require specification of surface meshes, and auto-refine their grid to resolve flow gradients, putting resolution where it is required without a priori user input. The ability of mSrc to use such radically unstructured flow input results in an efficient method of estimating noise from jet flows from complex nozzles installed on aircraft. Many validation cases are presented to demonstrate the accuracy and range of applicability of the mSrc method for representative jet noise applications.

Bridges, James↗
NASA NTRS2019

Rapid Prediction of Installed Jet Noise From RANS

A new method of computing jet noise, called mSrc, was developed on the general principles of acoustic analogies. In the method, the problem of translating turbulent flow energy into acoustic energy at a far-field observer is broken into two parts, a calculation of acoustic source strengths and then their propagation. The acoustic sources are related to turbulent quantities in the jet plume in a robust manner. The propagation, which is more properly computed using a Green's function accounting for nonuniform speed of sound and solid surfaces, is instead modeled using commonly observed features of jet acoustic far field directivity, and by diffraction barrier theory for surfaces. The mSrc method does not require gradients of the predicted flow field, allowing it to make use of robust unstructured RANS CFD methods, including embedded boundary codes. Such codes do not require specification of surface meshes, and auto-refine their grid to resolve flow gradients, putting resolution where it is required without a priori user input. The ability of mSrc to use such radically unstructured flow input results in an efficient method of estimating noise from jet flows from complex nozzles installed on aircraft. Many validation cases are presented to demonstrate the accuracy and range of applicability of the mSrc method for representative jet noise applications.

Bridges, James↗