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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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NASA NTRS1990

Time dependence of the earth's radiation fields determined from ERBS and NOAA-9 satellites

Satellite measurements from the Earth Radiation Budget Experiment (ERBE) are providing important quantitative data on the diurnal variability of broadband shortwave and longwave radiation. The results derived from the combination of the Earth Radiation Budget Satellite (ERBS) and NOAA-9 indicate that the largest diurnal variations in longwave radiation occur typically over deserts and over land areas which experience intense convective activity. Maximum values of the albedo diurnal amplitude factor are over oceans. Seasonal and cloud cover variations have important effects on the diurnal cycles of earth's radiation budget. ERBE results derived for individual regions are in substantial agreement with the diurnal results derived from the Geostationary Operational Environmental Satellite (GOES) measurements.

Harrison, E. F.↗
NASA NTRS2016

Tropospheric Emissions: Monitoring of Pollution (TEMPO)

TEMPO (Tropospheric Emissions: Monitoring of Pollution) was selected in 2012 by NASA as the first Earth Venture Instrument, for launch between 2018 and 2021. It will measure atmospheric pollution for greater North America from space using ultraviolet and visible spectroscopy. TEMPO observes from Mexico City, Cuba, and the Bahamas to the Canadian oil sands, and from the Atlantic to the Pacific, hourly and at high spatial resolution (approximately 2.1 kilometers N/S by 4.4 kilometers E/W at 36.5 degrees N, 100 degrees W). TEMPO provides a tropospheric measurement suite that includes the key elements of tropospheric air pollution chemistry, as well as contributing to carbon cycle knowledge. Measurements are made hourly from geostationary (GEO) orbit, to capture the high variability present in the diurnal cycle of emissions and chemistry that are unobservable from current low-Earth orbit (LEO) satellites that measure once per day. The small product spatial footprint resolves pollution sources at sub-urban scale. Together, this temporal and spatial resolution improves emission inventories, monitors population exposure, and enables effective emission-control strategies. TEMPO takes advantage of a commercial GEO host spacecraft to provide a modest cost mission that measures the spectra required to retrieve ozone (O3), nitrogen dioxide (NO2), sulfur dioxide (SO2), formaldehyde (H2CO), glyoxal (C2H2O2), bromine monoxide (BrO), IO (iodine monoxide),water vapor, aerosols, cloud parameters, ultraviolet radiation, and foliage properties. TEMPO thus measures the major elements, directly or by proxy, in the tropospheric O3 chemistry cycle. Multi-spectral observations provide sensitivity to O3 in the lowermost troposphere, substantially reducing uncertainty in air quality predictions. TEMPO quantifies and tracks the evolution of aerosol loading. It provides these near-real-time air quality products that will be made publicly available. TEMPO will launch at a prime time to be the North American component of the global geostationary constellation of pollution monitoring together with the European Sentinel-4 (S4) and Korean Geostationary Environment Monitoring Spectrometer (GEMS) instruments.

tropospheric measurement suite↗
NASA NTRSDate not supplied

Using the Diurnal Variability in GeoNEX TOA Reflectances for Earth Monitoring

Observations from the third-generation geostationary satellite instruments (GOES 16/17 ABI, Himawari 8/9 AHI, and etc.) have spatial resolution and spectral band configurations comparable to flagship LEO sensors (e.g., MODIS/VIIRS). More importantly, these data are acquired at very high temporal resolution, faithfully recording the variations of the full disk of Earth at every 5-10 minutes. They thus provide unique information about Earth’s atmosphere and surface. In order to explore the unique information content of geostationary data, this study systematically analyzes the diurnal variability in the GeoNEX L1G TOA reflectance products and compares them to simulated results by state-of-the-art radiative transfer codes. Our results show that • The smoothness of the TOA reflectance diurnal cycle provides a convenient and reliable way to identify stable atmospheric conditions and filter out passing clouds/shadows. • The diurnal variability of the blue band (0.47µm) reflectance is regulated mainly by atmospheric optical conditions over a majority of land cover types. As such, the diurnal variability of the blue band data allows us to retrieve AOD without invoking the use of spectral band ratios (SRC) as in previous algorithms. • In comparison, the diurnal variability of the short-wave infrared band (2.2µm) BRFs is mainly regulated by surface reflectance and the sun-target-satellite geometry. This information allows us to test and, if suitable, retrieve surface BRDF parameters. • Spectral band ratios, especially those between the 2.2µm and 0.47µm bands, are not constant but vary by locations and sun-target-satellite geometries. Our analysis clearly demonstrates that the information provided in high-frequent geostationary observations is unique and complementary to LEO sensors. Therefore, a synergy of GEO and LEO (and other) sensors has the great potential to improve existing remote sensing models and algorithms for better Earth monitoring.

Diurnal Variability↗
NASA NTRS1981

Solar EUV energy budget of the thermosphere

The considered study represents an extension of investigations reported by Torr et al. (1980). The earlier investigations are concerned with a quantification of thermospheric UV energy partitions for steady state conditions. The heating efficiency was determined as a function of altitude for selected conditions. Its value was found to vary dynamically as a function of altitude, season, latitude, and solar cycle. The steady state solution reported earlier is extended in the current study to a time dependent solution over a diurnal cycle. It is pointed out that the reported results will make necessary a significant revision of thermospheric models. Thus, estimates of additional sources such as Joule heating obtained from global thermospheric circulation models will require reevaluation.

Torr, M. R.↗
NASA NTRS2007

Geo-STAR: A Geostationary Microwave Sounder for the Future

The Geostationary Synthetic Thinned Aperture Radiometer (GeoSTAR) is a new Earth remote sensing instrument concept that has been under development at the Jet Propulsion Laboratory. First conceived in 1998 as a NASA New Millennium Program mission and subsequently developed in 2003-2006 as a proof-of-concept prototype under the NASA Instrument Incubator Program, it is intended to fill a serious gap in our Earth remote sensing capabilities - namely the lack of a microwave atmospheric sounder in geostationary orbit. The importance of such observations have been recognized by the National Academy of Sciences National Research Council, which recently released its report on a 'Decadal Survey' of NASA Earth Science activities1. One of the recommended missions for the next decade is a geostationary microwave sounder. GeoSTAR is well positioned to meet the requirements of such a mission, and because of the substantial investment NASA has already made in GeoSTAR technology development, this concept is fast approaching the necessary maturity for implementation in the next decade. NOAA is also keenly interested in GeoSTAR as a potential payload on its next series of geostationary weather satellites, the GOES-R series. GeoSTAR, with its ability to map out the three-dimensional structure of temperature, water vapor, clouds, precipitation and convective parameters on a continual basis, will significantly enhance our ability to observe hurricanes and other severe storms. In addition, with performance matching that of current and next generation of low-earth-orbiting microwave sounders, GeoSTAR will also provide observations important to the study of the hydrologic cycle, atmospheric processes and climate variability and trends. In particular, with GeoSTAR it will be possible to fully resolve the diurnal cycle. We discuss the GeoSTAR concept and basic design, the performance of the prototype, and a number of science applications that will be possible with GeoSTAR. The work reported on here was performed at the Jet Propulsion Laboratory, California Institute of Technology under a contract with the National Aeronautics and Space Administration.

Geostationary Synthetic Thinned Aperture Radiomete↗
NASA NTRS1987

Optical thickness of the Olympus cloud

Results are presented from a model of telescope observations that indicate a diurnal cycle exist, at least at one location, in the Martian atmosphere. By comparing calculated intensities with observed intensities of reflected sunlight, the diurnal variations in the optical thickness of the Olympus cloud that forms near the summit of Olympus Mons during summer was estimated. The results indicate that the optical depth at 0.4 microns rises sharply from near zero in late morning to about 0.8 in the early afternoon.

Narumi, Y.↗
NASA NTRS2002

Configuration and Intraseasonal Duration of Interannual Anomalies of the Great Plains Low-Level Jet

Despite the fact that the low-level jet of the southern Great Plains (the GPLLJ) of the U.S. is primarily a nocturnal phenomenon that virtually vanishes during the daylight hours, it is one of the most persistent and stable climatological features of the low-level continental flow during the warm-season months, May through August. We have used significant-level data to validate the skill of the GEOS-1 Data Assimilation System (DAS) in realistically detecting this jet and inferring its structure and evolution. We have then carried out a 15-year reanalysis with the GEOS-1 DAS to determine its climatology and mean diurnal cycle and to study its interannual variability. Interannual anomalies of the meridional flow associated with the GPLLJ are much smaller than the mean diurnal fluctuations, than random intraseasonal anomalies, and than the mean wind itself. There are three maxima of low-level meridional flow variance over the Great Plains and the Gulf of Mexico: a 1.2 m2 s-2 peak over the southeast Texas, to the east and south of the mean velocity peak, a 1.0 m2 s-2 peak over the western Gulf of Mexico, and a .8 m2 s-2 peak over the upper Great Plains (UGP), near the Nebraska/South Dakota border. Each of the three variance maxima corresponds to a spatially coherent, jet-like pattern of low-level flow interannual variability. There are also three dominant modes of interannual variability corresponding to the three variance maxima, but not in a simple one-to-one relationship. Cross-sectional profiles of mean southerly wind over Texas remain relatively stable and recognizable from year to year with only its eastward flank showing significant variability. This variability, however, exhibits a distinct, biennial oscillation during the first six to seven years of the reanalysis period and only then. This intermittent biennial oscillation (IBO, one of the three modes discussed in the previous paragraph) in the lowlevel flow is restricted to the region surrounding eastern Texas and is also evident in the NCEP/NCAR reanalysis data set from about 1978 to 1985 or 1986 and again from 1995 to 2000. It is evident as well in surface pressure in both the GEOS-1 and NCEP/NCAR sets. The interannual anomalies do not necessarily persist uniformly throughout an entire season, but can fluctuate from one part of the season to the next. To estimate the characteristic sub-seasonal time scales for coherence of these fluctuations, we have taken the weekly anomaly of low-level wind at each point of the domain from the climatological average for that given point and that given week of the season and computed the covariance of its fluctuations over all weeks and over all years with the weekly climatological anomaly of the meridional wind at each of the three reference points discussed above. The typical duration of a coherent interannual anomaly within a given warm season increases with decreasing latitude from 2 to 3 weeks over the UGP, to 6 to 7 weeks over eastern Texas. Coherence over the western Gulf of Mexico is intermediate between the two with a typical duration of 4 to 5 weeks. There appears to be evidence that the interannual anomalies over Texas the Gulf propagate to the UGP after a week and those over the Gulf propagate there after 2 to 3 weeks. There also appears to be some reverse propagation of interannual anomalies over the UGP to Texas and to the Gulf after a period of about one week. The interannual anomalies in southerly flow over eastern Texas seem to correlate well with interannual anomalies of surface temperature and (negative) ground wetness and over western Texas.

Helfand, H. M.↗
NASA NTRS1999

Interaction Between Tropical Convection and its Embedding Environment: An Energetics Analysis of a 2-D Cloud Resolving Simulation

The phase relation between the perturbation kinetic energy (K') associated with the tropical convection and the horizontal-mean moist available potential energy (bar-P) associated with environmental conditions is investigated by an energetics analysis of a numerical experiment. This experiment is performed using a 2-D cloud resolving model forced by the TOGA-COARE derived vertical velocity. The imposed upward motion leads to a decrease of bar-P directly through the associated vertical advective cooling, and to an increase of K' directly through cloud related processes, feeding the convection. The maximum K' and its maximum growth rate lags and leads, respectively, the maximum imposed large-scale upward motion by about 1-2 hours, indicating that convection is phase locked with large-scale forcing. The dominant life cycle of the simulated convection is about 9 hours, whereas the time scales of the imposed large-scale forcing are longer than the diurnal cycle. In the convective events, maximum growth of K' leads maximum decay of the perturbation moist available potential energy (P') by about 3 hours through vertical heat transport by perturbation circulation, and perturbation cloud heating. Maximum decay of P' leads maximum decay of bar-P by about one hour through the perturbation radiative, processes, the horizontal-mean cloud heating, and the large-scale vertical advective cooling. Therefore, maximum gain of K' occurs about 4-5 hours before maximum decay of bar-P.

Li, Xiaofan↗
DOE OSTI2023

Spatial and temporal metagenomics of river compartments reveals viral community dynamics in an urban impacted stream

Although river ecosystems constitute a small fraction of Earth’s total area, they are critical modulators of microbially and virally orchestrated global biogeochemical cycles. However, most studies either use data that is not spatially resolved or is collected at timepoints that do not reflect the short life cycles of microorganisms. To address this gap, we assessed how viral and microbial communities change over a 48-hour period by sampling surface water and pore water compartments of the wastewater-impacted River Erpe in Germany. We sampled every 3 hours resulting in 32 samples for which we obtained metagenomes along with geochemical and metabolite measurements. From our metagenomes, we identified 6,500 viral and 1,033 microbial metagenome assembled genomes (MAGs) and found distinct community membership and abundance associated with each river compartment (e.g., Competibacteraceae in surfacewater and Sulfurimonadaceae in pore water). We show that 17% of our viral MAGs clustered to viruses from other ecosystems like wastewater treatment plants and rivers. Our results also indicated that 70% of the viral community was persistent in surface waters, whereas only 13% were persistent in the pore waters taken from the hyporheic zone. Finally, we predicted linkages between 73 viral genomes and 38 microbial genomes. These putatively linked hosts included members of the Competibacteraceae, which we suggest are potential contributors to river carbon and nitrogen cycling via denitrification and nitrogen fixation. Together, these findings demonstrate that members of the surface water microbiome from this urban river are stable over multiple diurnal cycles. These temporal insights raise important considerations for ecosystem models attempting to constrain dynamics of river biogeochemical cycles.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS2002

Raman Lidar Profiling of Aerosols Over the Central US; Diurnal Variability and Comparisons with the GOCART Model

We use profiles of aerosol extinction, water vapor mixing ratio, and relative humidity measured by the ARM SGP Raman lidar in northern Oklahoma to show how the vertical distributions of aerosol extinction and water vapor vary throughout the diurnal cycle. While significant (20-30%) variations in aerosol extinction occurred near the surface as well as aloft, smaller (approximately 10%) variations were observed in the diurnal variability of aerosol optical thickness (AOT). The diurnal variations in aerosol extinction profiles are well correlated with corresponding variations in the average relative humidity profiles. The water vapor mixing ratio profiles and integrated water vapor amounts generally show less diurnal variability. The Raman lidar profiles are also used to evaluate the aerosol optical thickness and aerosol extinction profiles simulated by the GOCART global aerosol model. Initial comparisons show that the AOT simulated by GOCART was in closer agreement with the AOT derived from the Raman lidar and Sun photometer measurements during November 2000 than during September 2000. For both months, the vertical variability in average aerosol extinction profiles simulated by GOCART is less than the variability in the corresponding Raman lidar profiles.

Ferrare, R. A.↗
NASA NTRS2010

Ten-Year Climatology of Summertime Diurnal Rainfall Rate Over the Conterminous U.S.

Diurnal cycles of summertime rainfall rates are examined over the conterminous United States, using radar-gauge assimilated hourly rainfall data. As in earlier studies, rainfall diurnal composites show a well-defined region of rainfall propagation over the Great Plains and an afternoon maximum area over the south and eastern portion of the United States. Zonal phase speeds of rainfall in three different small domains are estimated, and rainfall propagation speeds are compared with background zonal wind speeds. Unique rainfall propagation speeds in three different regions can be explained by the evolution of latent-heat theory linked to the convective available potential energy, than by gust-front induced or gravity wave propagation mechanisms.

Matsui, Toshihisa↗
NASA NTRS2012

An Alternative Inter-Satellite Calibration of the UMD HIRS OLR Retrievals

Outgoing Longwave Radiation (OLR) at the top-of-atmosphere (TOA) is a fundamental component of Earth's energy balance and represents the heat energy in the thermal bands rejected to space by the planet. Determination of OLR from satellites has a long and storied history, but the observational record remains largely fragmented with gaps in satellite measurements over the past three decades. Perhaps the most semi-continuous set of retrievals comes from the University of Maryland (UMD) algorithm that uses four HIRS (High Resolution Infrared Sounder) channels on the NOAA polar orbiting satellites to estimate OLR. This data set shows great promise in helping to bridge the discontinuous ERBS (Earth Radiation Budget Satellite) and CERES (Clouds and the Earth s Radiant Energy System) measurements. However, significant satellite inter-calibration biases persist with the present UMD data, principally outside the tropics. Difficulties relate to the combination of drift of the satellite equator crossing time through the diurnal cycle and changes in HIRS channel response function design. Here we show how an ad hoc recalibration of the UMD retrievals among the different satellites removes much of the remaining uncertainty due to diurnal drift of the satellite orbit. The adjusted HIRS data (using no other external information) show much better agreement with OLR from the European Center Interim Reanalysis (EC-Int), longer-term signals in the Global Energy and Water Cycle Experiment / Surface Radiation Budget (GEWEX/SRB) retrievals, and also agree well with ERBS and CERES OLR measurements. These results augur well for narrowing the uncertainties in multi-decadal estimates of this important climate variable.

Robertson, Franklin R.↗
NASA NTRS1988

Diurnal variability of the planetary albedo - An appraisal with satellite measurements and general circulation models

An atmospheric radiation model is used here to illustrate several features associated with modeling the diurnal cycle of the planetary albedo. It is found that even for clear regions there appear to be deficiencies in our knowledge of how to model this quantity. The diurnal amplitude factor, defined as the ratio of the diurnally averaged planetary albedo to that at noon, between two GCMs and measurements made from a geostationary satellite. While reasonable consistency is found, the comparisons underscore difficulties associated with converting local-time albedo measurements, as made from sun-synchronous satellites, to diurnally averaged albedos.

Potter, G. L.↗
DOE OSTI2023

New-generation geostationary satellite reveals widespread midday depression in dryland photosynthesis during 2020 western U.S. heatwave

Emerging new-generation geostationary satellites have broadened the scope for studying the diurnal cycle of ecosystem functions. We exploit observations from the Geostationary Operational Environmental Satellite-R series to examine the effect of a severe U.S. heatwave in 2020 on the diurnal variations of ecosystem photosynthesis. We find divergent responses of photosynthesis to the heatwave across vegetation types and aridity gradients, with drylands exhibiting widespread midday and afternoon depression in photosynthesis. The diurnal centroid and peak time of dryland gross primary production (GPP) substantially shift toward earlier morning times, reflecting notable water and heat stress. Our geostationary satellite-based method outperforms traditional radiation-based upscaling methods from polar-orbiting satellite snapshots in estimating daily GPP and GPP loss during heatwaves. These findings underscore the potential of geostationary satellites for diurnal photosynthesis monitoring and highlight the necessity to consider the increased diurnal asymmetry in GPP under stress when evaluating carbon-climate interactions.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS1991

Overpressurized zero pressure balloon system

Typical zero pressure scientific balloon systems experiencing diurnal cycles require on board expendable ballast to maintain design float altitude. In the past, pressurized balloon systems have been employed to overcome the need for ballast while maintaining small diurnal altitude excursions. However, requirements on material characteristics and manufacturing methods have enforced limitations on balloon size and therefore payload and altitude capabilities. This effort was aimed at considering the use of current (or slightly modified) zero pressure balloon systems (design, manufacturing and materials) as candidates for pressurized vehicles. Data gathered through performance analysis, structural analysis and flight testing has shown that the use of current zero pressure designs can be expanded to enhance balloon performance.

Simpson, Joel M.↗
NASA NTRS1991

Geostationary earth climate sensor: Scientific utility and feasibility, phase A

The possibility of accurate broad band radiation budget measurements from a GEO platform will provide a unique opportunity for viewing radiation processes in the atmosphere-ocean system. The CSU/TRW team has prepared a Phase 1 instrument design study demonstrating that measurements of radiation budget are practical from geosynchronous orbit with proven technology. This instrument concept is the Geostationary Earth Climate Sensor (GECS). A range of resolutions down to 20 km at the top of the atmosphere are possible, depending upon the scientific goals of the experiment. These tradeoffs of resolution and measurement repeat cycles are examined for scientific utility. The design of a flexible instrument is shown to be possible to meet the two goals: long-term, systematic monitoring of the diurnal cycles of radiation budget; and high time and space resolution studies of regional radiation features.

Campbell, G. Garrett↗
NASA NTRS1994

Diurnal heating and cloudiness in the NCAR Community Climate Model (CCM2)

In this paper, the authors assess the suitability of the heating fileds in the latest version of the National Center for Atmospheric Research (NCAR) Community Climate Model (CCM2) for modeling the thermal forcing of atmospheric tides. Accordingly, diurnal variations of the surface pressure, outgoing longwave radiation (OLR), cloudiness, and precipitation are examined in the CCM2. The fields of radiative, sensible, and latent heating are similarly analyzed. These results are subjectively compared with available data. Equatorial diurnal surface pressure tides are fairly well simulated by CCM2. The model successfully reproduces the semidiurnal surface pressure tides; however, this may result in part from reflection of wave energy at the upper boundary. The CCM2 large-scale diurnal OLR is generally consistent with observations. The moist-convective scheme in the model is able to reproduce the diurnally varying cloudiness and precipitation patterns associated with land-sea contrasts; however, the amplitudes of CCM2 diurnal continental convective cloudiness are weaker than observations. The CCM2 boundary-layer sensible heating is consistent with a very limited set of observations, and with estimates obtained from simple models of diffusive heating. Although the CCM2 tropospheric solar radiative heating is similar in magnitude to previous estimates, there are substantial differences in the vertical structures. A definitive assessment of the validity of the CCM2 diurnal cycle is precluded by the lack of detailed observations and the limitations of our CCM2 sample. Nevertheless, the authors conclude that the global-scale components of the CCM2 diurnal heating are useful proxies for the true diurnal forcing of the tides.

Lieberman, Ruth S.↗