Search NASA⌕ Search

SEARCH · Search NASA

Results for “Atmospheric Radiation Measurement”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 415 records · Page 23
All sourcesNASA NTRSDOE OSTI
NASA NTRS2005

Sulfur Oxidation and Contrail Precursor Chemistry

Sulfuric acid (H2SO4), formed in commercial aircraft operations via Fuel-S (right arrow) SO2 + SO3 (right arrow) H2SO4, plays an important role in affecting the global climate change through atmospheric chemical reactions and radiative forcing. Measurement of the sulfur oxidation rates is critical to the understanding of the contrail formation. The principle reaction pathway is SO2 + O + M (right arrow) SO3 + M. Although there are many measurements for the rates of this reaction, it has never been measured in the temperature and pressure regime available to aircraft operation. In this investigation, a series of experiments were performed behind the reflected shock waves in a shock tube. OH radicals were produced in lean, shock heated SO2/H2/O2/Ar mixtures. The reaction progress was followed using OH absorption spectroscopy at 310 nm. The data were analyzed with the aid of computer modeling/simulation. The mean value of the rate coefficients of R21 determined is k(sub 21,0)/[M]= 3.9 x 10(exp 15) cm(sup 6) per square mole per second at T = 960 - 1150 K and rho = 16-30 micromole per cubic centimeter with uncertainty limits of plus or minus 30%. A non-Arrhenius fit to our data together with all existing data gives k(sub 21,0)/[M] = 1.3 x 10(exp 24) T (exp -2.5) exp(-2350 K/T) cm(sup 6) per square mole per second at T = 300 - 2500 K with the same uncertainty limits given above. The calculated conversion of S(IV)(SO2) to S(VI) (SO3 + H2SO4) was about 2% in our experimental conditions.

DeWitt, Kenneth↗
NASA NTRS2012

Retrieving Atmospheric Temperature and Moisture Profiles from NPP CRIS/ATMS Sensors Using Crimss EDR Algorithm

The Joint Polar Satellite System (JPSS) is a U.S. National Oceanic and Atmospheric Administration (NOAA) mission in collaboration with the U.S. National Aeronautical Space Administration (NASA) and international partners. The NPP Cross-track Infrared Microwave Sounding Suite (CrIMSS) consists of the infrared (IR) Crosstrack Infrared Sounder (CrIS) and the microwave (MW) Advanced Technology Microwave Sounder (ATMS). The CrIS instrument is hyperspectral interferometer, which measures high spectral and spatial resolution upwelling infrared radiances. The ATMS is a 22-channel radiometer similar to Advanced Microwave Sounding Units (AMSU) A and B. It measures top of atmosphere MW upwelling radiation and provides capability of sounding below clouds. The CrIMSS Environmental Data Record (EDR) algorithm provides three EDRs, namely the atmospheric vertical temperature, moisture and pressure profiles (AVTP, AVMP and AVPP, respectively), with the lower tropospheric AVTP and the AVMP being JPSS Key Performance Parameters (KPPs). The operational CrIMSS EDR an algorithm was originally designed to run on large IBM computers with dedicated data management subsystem (DMS). We have ported the operational code to simple Linux systems by replacing DMS with appropriate interfaces. We also changed the interface of the operational code so that we can read data from both the CrIMSS science code and the operational code and be able to compare lookup tables, parameter files, and output results. The detail of the CrIMSS EDR algorithm is described in reference [1]. We will present results of testing the CrIMSS EDR operational algorithm using proxy data generated from the Infrared Atmospheric Sounding Interferometer (IASI) satellite data and from the NPP CrIS/ATMS data.

Liu, X.↗
NASA NTRS1992

Experimental study and improved modeling of high-temperature air radiation

Spectral emission measurements were conducted in an atmospheric pressure air plasma. The thermodynamic state of the plasma was determined to be close to local thermodynamic equilibrium (LTE), and the temperature profile was measured. The spectrum emitted by the plasma over the range 2,000 to 8,000 A was recorded and calibrated. This spectrum comprises the major radiating molecular bands and atomic lines in air, and is therefore proposed as a benchmark to test radiative calculations. A comparison of these results with the predictions of the NEQAIR code induced several modeling improvements in the code. In particular, radiative transition probabilities and spectroscopic constants were updated, and additional band systems of NO (NO Delta, Epsilon, Beta prime and Gamma prime) were included. Since the C state from which the NO Delta transition originates is predissociated, a simplified collision-predissociation model for this state was added to the code. These changes are presented, and their effect discussed.

Laux, Christophe O.↗
NASA NTRS2000

Airborne Solar Radiant Flux Measurements During ACE-2

Aerosol effects on atmospheric radiative fluxes provide a forcing function that can change the climate in potentially significant ways. This aerosol radiative forcing is a major source of uncertainty in understanding the climate change of the past century and predicting future climate. To help reduce this uncertainty, the 1996 Tropospheric Aerosol Radiative Forcing Observational Experiment (TARFOX) and the 1997 Aerosol Characterization Experiment (ACE-2) measured the properties and radiative effects of aerosols over the Atlantic Ocean. In the ACE 2 program the solar radiant fluxes were measured on the Pelican aircraft and the UK Met Office C130. This poster will show results from the measurements for the aerosol effects during the clear column days. We will compare the results with calculations of the radiant fluxes.

Bergstrom, Robert W.↗
NASA NTRS2003

Angular Distribution Models for Top-of-Atmosphere Radiative Flux Estimation from the Clouds and the Earth's Radiant Energy System Instrument on the Tropical Rainfall Measuring Mission Satellite: Methodology - Part 1

Clouds and the Earth s Radiant Energy System (CERES) investigates the critical role that clouds and aerosols play in modulating the radiative energy flow within the Earth-atmosphere system. CERES builds upon the foundation laid by previous missions, such as the Earth Radiation Budget Experiment, to provide highly accurate top-of-atmosphere (TOA) radiative fluxes together with coincident cloud and aerosol properties inferred from high-resolution imager measurements. This paper describes the method used to construct empirical angular distribution models (ADMs) for estimating shortwave, longwave, and window TOA radiative fluxes from CERES radiance measurements on board the Tropical Rainfall Measuring Mission satellite. To construct the ADMs, multiangle CERES measurements are combined with coincident high-resolution Visible Infrared Scanner measurements and meteorological parameters from the European Centre for Medium-Range Weather Forecasts data assimilation product. The ADMs are stratified by scene types defined by parameters that have a strong influence on the angular dependence of Earth's radiation field at the TOA. Examples of how the new CERES ADMs depend upon the imager-based parameters are provided together with comparisons with existing models.

Loeb, N. G.↗
NASA NTRS1992

Correlation of solar irradiance and atmospheric temperature variations derived from spacecraft radiometry

Long-term changes in the mean global atmospheric temperature and the total solar irradiance were examined utilizing 1979-1989 spacecraft measurements. Outgoing longwave radiation at the top of the atmosphere was employed to infer global atmospheric temperatures. Evidence was determined that indicates the global temperatures should decline in the 1990-1997 period as the magnitude of the incoming solar irradiance declines with decreasing solar magnetic activity.

Lee, Robert B., III↗
NASA NTRS1983

Relationships between chlorophyll density and ocean radiance as measured by U2/OCS: Algorithms, examples and comparison

An ocean atmosphere radiative transfer process computation method which is suitable for determining lower boundary ocean albedo and other radiation components from spectral measurements of upwelling radiance taken from a high altitude platform is described. The method was applied to a set of color scanner data taken from slope water of the South Atlantic Bight to determine the influence of cholorophyll-a pigments in the sea on the ratio of upwelling radiance to down welling irradiance as a function of wavelength. The resulting chlorophyll concentrations are compared with measurements made by ships stationed along the flight path.

Kim, H. H.↗
NASA NTRSDate not supplied

International Satellite Cloud Climatology Project (ISCCP) Stage D2 Monthly Cloud Product - Revised Algorithm in Native (NAT) Data Format (ISCCP_D2_NAT)

Since 1983 an international group of institutions has collected and analyzed satellite radiance measurements from up to five geostationary and two polar orbiting satellites to infer the global distribution of cloud properties and their diurnal, seasonal and interannual variations. The primary focus of the first phase of the project (1983-1995) was the elucidation of the role of clouds in the radiation budget (top of the atmosphere and surface). In the second phase of the project (1995 onwards) the analysis also concerns improving understanding of clouds in the global hydrological cycle. [Location=TROPOSPHERE] [Temporal_Coverage: Start_Date=1983-07-01; Stop_Date=] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Latitude_Resolution=280 Km; Longitude_Resolution=280 Km; Temporal_Resolution=Monthly].

CLOUD OPTICAL THICKNESS↗
NASA NTRS1984

Clouds and aerosols in Saturn's atmosphere

The physical properties and spatial distribution of aerosol and cloud particles in Saturn's atmosphere are discussed based on data from remote measurement of scattered solar radiation and thermal radiation emitted from Saturn's atmosphere. A brief overview of the relations between particle properties and the scattered and emitted radiation field is given, and observations of Saturn at wavelengths from the ultraviolet to the thermal infrared which bear on the atmosphere's aerosol and cloud properties are reviewed. The single-scattering properties of the particles deduced from observations are discussed, commenting on the possible composition of the particles. The implications of the observations for the vertical and horizontal distribution of the clouds and aerosols are reviewed, and current information and areas for further research on the clouds and aerosols are summarized.

Tomasko, M. G.↗
NASA NTRS2017

Measurements of the Magnetic Field of the Upper Chromosphere with Polarimetry

A major remaining challenge for heliophysics is to decipher the magnetic structure of the chromosphere. The chromosphere is the critical interface between the Sun's photosphere and corona: it contains more mass than the entire interplanetary heliosphere, requires a heating rate that is larger than that of the corona, and mediates all the energy driving the solar wind, solar atmospheric heating and solar eruptions. While measurements of the magnetic field in the photosphere are routine, the chromosphere poses several extra challenges. The magnetically sensitive lines formed in the upper chromosphere are in the ultraviolet, so space-based observations are required. The lines are often formed over a range of heights, sampling different plasma which complicates the inversion process. These lines are sensitive to the magnetic field via polarized light that is created or modified through the Hanle and Zeeman effects. There are a few observations of these lines, and a significant challenge remains in extracting the magnetic field from the polarization measurements, as detailed model atmospheres with advanced radiative transfer physics are needed. Real progress is obtained by a simultaneous improvement in both the observational side and the modeling side. We present information on the CLASP (Chromospheric LAyer Spectro-Polarimeter) sounding rocket program, and future prospects for these types of measurements.

Solar; Chromosphere; Polarization↗
NASA NTRSDate not supplied

Airborne Remote Sensing Measurements of Particles in Different Parts of the World

Around the globe, atmospheric aerosols pose a significant yet uncertain impact on the Earth's climate, environmental air quality and human health. Suborbital sunphotometer measurements of Aerosol Optical Depth (AOD) (i.e., the amount of direct-beam solar light attenuated by aerosols within the atmospheric column) are used to validate satellite aerosol retrievals and are valuable when studying aerosol-solar radiation and/ or aerosol-cloud interactions. Since 1985, NASA Ames Research Center (ARC) has been using airborne sun-tracking sunphotometers to measure atmospheric constituents such as aerosols, clouds, and gases. The NASA Ames Airborne Tracking Sunphotometer (AATS-6) and then (AATS-14) operate by tracking the sun and measuring the transmission of solar radiation in 6 to 14 discrete spectral channels (Russell et al., 1986). The AATS systems were followed by the more advanced hyperspectral 4STAR instrument (Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research; Dunagan et al., 2013), which combines the airborne sun-tracking capability of the AATS-14 with a sky scanning feature similar to the ground-based Aerosol Robotic Network Sun/sky photometers (AERONET). We present a comprehensive analysis of ~30 airborne campaigns undertaken by NASA and DoE based on a new database of airborne sunphotometer measurements. Using this database, we present a clear picture of airborne AODs over the range of historical campaigns and the aerosol sizes per region, especially over the ocean where AERONET data is limited. With this database, we can investigate systematic differences in AOD such as those observed over different land and ocean surfaces in specific geographical regions. Finally, we will briefly show comparisons with satellite aerosol retrievals from MODIS and/or VIIRS. Russell, P. B., T. Matsumoto, V. J. Banta, J. M. Livingston, C. Mina, D. S. Colburn, and R. F. Pueschel (1986), Measurements with an airborne, autotracking, external-head sunphotometer, Preprint Volume, Sixth Conference on Atmospheric Radiation, May 13–16, 1986, Amer. Meteor.Soc., Boston, MA, 55–58. Dunagan, Stephen E., et al. "Spectrometer for sky-scanning sun-tracking atmospheric research (4STAR): Instrument technology." Remote Sensing 5.8 (2013): 3872-3895

Brendan Stover Cornelison↗
NASA NTRS1994

Arctic ocean radiative fluxes and cloud forcing estimated from the ISCCP C2 cloud dataset, 1983-1990

Radiative fluxes and cloud forcings for the ocean areas of the Arctic are computed from the monthly cloud product of the International Satellite Cloud Climatology Project (ISCCP) for 1983-90. Spatially averaged short-wave fluxes are compared well with climatological values, while downwelling longwave fluxes are significantly lower. This is probably due to the fact that the ISCCP cloud amounts are underestimates. Top-of-the-atmosphere radiative fluxes are in excellent agreement with measurements from the Earth Radiation Budget Experiment (ERBE). Computed cloud forcings indicate that clouds have a warming effect at the surface and at the top of the atmosphere during winter and a cooling effect during summer. The net radiative effect of clouds is larger at the surface during winter but greater at the top of the atmosphere during summer. Overall the net radiative effect of clouds at the top of the atmosphere is one of cooling. This is in contrast to a previous result from ERBE data showing arctic cloud forcings have a net warming effect. Sensitivities to errors in input parameters are generally greater during winter with cloud amount being the most important paarameter. During summer the surface radiation balance is most sensitive to errors in the measurements of surface reflectance. The results are encouraging, but the estimated error of 20 W/sq m in surface net radiative fluxes is too large, given that estimates of the net radiative warming effect due to a doubling of CO2 are on the order of 4 W/sq m. Because it is difficult to determine the accuracy of results with existing in situ observations, it is recommended that the development of improved algorithms for the retrieval of surface radiative properties be accompanied by the simultaneous assembly of validation datasets.

Schweiger, Axel J.↗
NASA NTRS1982

Comparison of LANDSAT-2 and field spectrometer reflectance signatures of south Texas rangeland plant communities

The accuracy was assessed for an atmospheric correction method that depends on clear water bodies to infer solar and atmospheric parameters for radiative transfer equations by measuring the reflectance signature of four prominent south Texas rangeland plants with the LANDSAT satellite multispectral scanner (MSS) and a ground based spectroradiometer. The rangeland plant reflectances produced by the two sensors were correlated with no significant deviation of the slope from unity or of the intercept from zero. These results indicated that the atmospheric correction produced LANDSAT MSS estimates of rangeland plant reflectances that are as accurate as the ground based spectroradiometer.

Richardson, A. J.↗
NASA NTRS2016

The CubeSat Infrared Atmospheric Sounder (CIRAS), Pathfinder for the Earth Observing Nanosatellite-Infrared (EON-IR)

The CubeSat Infrared Atmospheric Sounder (CIRAS) will measure upwelling infrared radiation of the Earth in the MWIR region of the spectrum from space on a CubeSat. CIRAS will demonstrate two new infrared sounding technologies. The first is a 2D array of High Operating Temperature Barrier Infrared Detector (HOT-BIRD) material, selected for its high uniformity, low cost, low noise and higher operating temperatures than traditional materials. The detectors are hybridized to a commercial ROIC and commercial camera electronics. The second technology is an MWIR Grating Spectrometer (MGS) to be designed and developed by Ball Aerospace to provide imaging spectroscopy for atmospheric sounding in a CubeSat volume. The MGS has no moving parts and is based on heritage spectrometers including the Ball Aerospace Spaceborne Infrared Atmospheric Sounder for GEO (SIRAS-G) IIP of 2007. JPL will develop the mechanical, electronic and thermal subsystems for CIRAS. The spacecraft will be a commercially available CubeSat. The integrated system will be a complete 6U CubeSat capable of measuring temperature and water vapor profiles with good lower tropospheric sensitivity. The CIRAS is the first step towards the development of an Earth Observing Nanosatellite Infrared (EON-IR) for potential use in a future operational forecasting system.

Pagano, Thomas↗
NASA NTRS1990

Nimbus 7 solar backscatter ultraviolet (SBUV) ozone products user's guide

Three ozone tape products from the Solar Backscatter Ultraviolet (SBUV) experiment aboard Nimbus 7 were archived at the National Space Science Data Center. The experiment measures the fraction of incoming radiation backscattered by the Earth's atmosphere at 12 wavelengths. In-flight measurements were used to monitor changes in the instrument sensitivity. Total column ozone is derived by comparing the measurements with calculations of what would be measured for different total ozone amounts. The altitude distribution is retrieved using an optimum statistical technique for the inversion. The estimated initial error in the absolute scale for total ozone is 2 percent, with a 3 percent drift over 8 years. The profile error depends on latitude and height, smallest at 3 to 10 mbar; the drift increases with increasing altitude. Three tape products are described. The High Density SBUV (HDSBUV) tape contains the final derived products - the total ozone and the vertical ozone profile - as well as much detailed diagnostic information generated during the retrieval process. The Compressed Ozone (CPOZ) tape contains only that subset of HDSBUV information, including total ozone and ozone profiles, considered most useful for scientific studies. The Zonal Means Tape (ZMT) contains daily, weekly, monthly and quarterly averages of the derived quantities over 10 deg latitude zones.

Fleig, Albert J.↗
NASA NTRS1996

Galileo Space Probe News Conference

This NASA Kennedy Space Center (KSC) video release presents Part 1 of a press conference regarding the successful entry of the Galileo Space Probe into Jupiter's atmosphere. The press conference panel is comprised of twelve principal investigators and project scientists that oversee the Galileo mission. Among these panelists, William J. O'Neil (Jet Propulsion Lab.) begins the video praising all of the scientists that worked on the orbiter mission. He then presents a visual overview of Galileo's overall mission trajectory and schedule. Marcie Smith (NASA Ames Research Center) then describes the Galileo Probe mission and the overall engineering and data acquisition aspects of the Probe's Jupiter atmospheric entry. Dr. Richard Young (NASA Ames Research Center) follows with a brief scientific overview, describing the measurements of the atmospheric composition as well as the instruments that were used to gather the data. Atmospheric pressure, temperature, density, and radiation levels of Jupiter were among the most important parameters measured. It is explained that these measurements would be helpful in determining among other things, the overall dynamic meteorology of Jupiter. A question and answer period follows the individual presentations. Atmospheric thermal structure, water abundances, wind profiles, radiation, cloud structure, chemical composition, and electricity are among the topics discussed. Parts 2 and 3 of the press conference can be found in document numbers NONP-NASA-VT-2000001074, and NONP-NASA-VT-2000001075.

Source record↗
NASA NTRS1992

SUMER: Temperatures, densities, and velocities in the outer solar atmosphere

The SUMER (Solar Ultraviolet Measurement of Emitted Radiation) instrumentation that will be mounted on the SOHO (Solar and Heliospheric Observatory) spacecraft is in development. It has some capability of improving the solar angular resolution and the spectral resolution already obtained in the far UV to the extreme UV, corresponding to the temperature range between 10,000 and a few 1,000,000 K. Some insights into the SUMER spectrometer, developed to study the dynamics and to infer temperatures and densities of the low corona and the chromosphere-corona transition zone in using the 50 to 160 nm wavelength range, are given. The SUMER scientific goals and the techniques used are outlined. The instrumentation and the expected performances are described. The way the observations can be conducted is emphasized and the operation of SUMER in coordination with other SOHO instrumentations and in cooperation with ground based observations is explained.

Lemaire, Philippe↗