40 research outputs found
Earth Resources: A continuing bibliography with indexes, issue 40
This bibliography lists 423 reports, articles, and other documents introduced into the NASA scientific and technical information system between October 1 and December 31, 1983. Emphasis is placed on the use of remote sensing and geophysical instrumentation in spacecraft and aircraft to survey and inventory natural resources and urban areas. Subject matter is grouped according to agriculture and forestry, environmental changes and cultural resources, geodesy and cartography, geology and mineral resources, hydrology and water management, data processing and distribution systems, instrumentation and sensors, and economical analysis
State of the climate in 2013
In 2013, the vast majority of the monitored climate variables reported here maintained trends established in recent decades. ENSO was in a neutral state during the entire year, remaining mostly on the cool side of neutral with modest impacts on regional weather patterns around the world. This follows several years dominated by the effects of either La Niña or El Niño events. According to several independent analyses, 2013 was again among the 10 warmest years on record at the global scale, both at the Earths surface and through the troposphere. Some regions in the Southern Hemisphere had record or near-record high temperatures for the year. Australia observed its hottest year on record, while Argentina and New Zealand reported their second and third hottest years, respectively. In Antarctica, Amundsen-Scott South Pole Station reported its highest annual temperature since records began in 1957. At the opposite pole, the Arctic observed its seventh warmest year since records began in the early 20th century. At 20-m depth, record high temperatures were measured at some permafrost stations on the North Slope of Alaska and in the Brooks Range. In the Northern Hemisphere extratropics, anomalous meridional atmospheric circulation occurred throughout much of the year, leading to marked regional extremes of both temperature and precipitation. Cold temperature anomalies during winter across Eurasia were followed by warm spring temperature anomalies, which were linked to a new record low Eurasian snow cover extent in May. Minimum sea ice extent in the Arctic was the sixth lowest since satellite observations began in 1979. Including 2013, all seven lowest extents on record have occurred in the past seven years. Antarctica, on the other hand, had above-average sea ice extent throughout 2013, with 116 days of new daily high extent records, including a new daily maximum sea ice area of 19.57 million km2 reached on 1 October. ENSO-neutral conditions in the eastern central Pacific Ocean and a negative Pacific decadal oscillation pattern in the North Pacific had the largest impacts on the global sea surface temperature in 2013. The North Pacific reached a historic high temperature in 2013 and on balance the globally-averaged sea surface temperature was among the 10 highest on record. Overall, the salt content in nearsurface ocean waters increased while in intermediate waters it decreased. Global mean sea level continued to rise during 2013, on pace with a trend of 3.2 mm yr-1 over the past two decades. A portion of this trend (0.5 mm yr-1) has been attributed to natural variability associated with the Pacific decadal oscillation as well as to ongoing contributions from the melting of glaciers and ice sheets and ocean warming. Global tropical cyclone frequency during 2013 was slightly above average with a total of 94 storms, although the North Atlantic Basin had its quietest hurricane season since 1994. In the Western North Pacific Basin, Super Typhoon Haiyan, the deadliest tropical cyclone of 2013, had 1-minute sustained winds estimated to be 170 kt (87.5 m s-1) on 7 November, the highest wind speed ever assigned to a tropical cyclone. High storm surge was also associated with Haiyan as it made landfall over the central Philippines, an area where sea level is currently at historic highs, increasing by 200 mm since 1970. In the atmosphere, carbon dioxide, methane, and nitrous oxide all continued to increase in 2013. As in previous years, each of these major greenhouse gases once again reached historic high concentrations. In the Arctic, carbon dioxide and methane increased at the same rate as the global increase. These increases are likely due to export from lower latitudes rather than a consequence of increases in Arctic sources, such as thawing permafrost. At Mauna Loa, Hawaii, for the first time since measurements began in 1958, the daily average mixing ratio of carbon dioxide exceeded 400 ppm on 9 May. The state of these variables, along with dozens of others, and the 2013 climate conditions of regions around the world are discussed in further detail in this 24th edition of the State of the Climate series. © 2014, American Meteorological Society. All rights reserved
GEOS-C ground truth program description document
Models and plans for in situ measurements required to calibrate and evaluate the altitude and sea state measurement capabilities of the GEOS-C radar altimeter are presented
The 1991 research and technology report, Goddard Space Flight Center
The 1991 Research and Technology Report for Goddard Space Flight Center is presented. Research covered areas such as (1) earth sciences including upper atmosphere, lower atmosphere, oceans, hydrology, and global studies; (2) space sciences including solar studies, planetary studies, Astro-1, gamma ray investigations, and astrophysics; (3) flight projects; (4) engineering including robotics, mechanical engineering, electronics, imaging and optics, thermal and cryogenic studies, and balloons; and (5) ground systems, networks, and communications including data and networks, TDRSS, mission planning and scheduling, and software development and test
COBE's search for structure in the Big Bang
The launch of Cosmic Background Explorer (COBE) and the definition of Earth Observing System (EOS) are two of the major events at NASA-Goddard. The three experiments contained in COBE (Differential Microwave Radiometer (DMR), Far Infrared Absolute Spectrophotometer (FIRAS), and Diffuse Infrared Background Experiment (DIRBE)) are very important in measuring the big bang. DMR measures the isotropy of the cosmic background (direction of the radiation). FIRAS looks at the spectrum over the whole sky, searching for deviations, and DIRBE operates in the infrared part of the spectrum gathering evidence of the earliest galaxy formation. By special techniques, the radiation coming from the solar system will be distinguished from that of extragalactic origin. Unique graphics will be used to represent the temperature of the emitting material. A cosmic event will be modeled of such importance that it will affect cosmological theory for generations to come. EOS will monitor changes in the Earth's geophysics during a whole solar color cycle
ALOS-2/PALSAR-2 Calibration, Validation, Science and Applications
Twelve edited original papers on the latest and state-of-art results of topics ranging from calibration, validation, and science to a wide range of applications using ALOS-2/PALSAR-2. We hope you will find them useful for your future research
Fourth National Aeronautics and Space Administration Weather and Climate Program Science Review
The NASA Weather and Climate Program has two major thrusts. The first involves the development of experimental and prototype operational satellite systems, sensors, and space facilities for monitoring and understanding the atmosphere. The second thrust involves basic scientific investigation aimed at studying the physical and chemical processes which control weather and climate. This fourth science review concentrated on the scientific research rather than the hardware development aspect of the program. These proceedings contain 65 papers covering the three general areas: severe storms and local weather research, global weather, and climate
Instrument wetting errors in hurricanes and a re-examination of inner-core thermodynamics
August 1999.Also issued as author's thesis (M.S.) -- Colorado State University, 1999.NSF ATM-9616818 and NOAA/CIRA NA67RJ0152 on cover.Includes bibliographical references.Thermodynamic errors caused by instrument wetting are thoroughly examined and are accurately removed from 579 radial legs of aircraft flight-level data in 27 hurricanes. Similar to previous studies, a radiometer is used to provide accurate temperatures in clouds and precipitation where immersion thermometers and cooled-mirror hygrometers typically experience large errors induced by instrument wetting. Theoretical temperature errors caused by the presence of hydrometeors in the sampled air are reviewed and discussed for each instrument. A correction method is developed to remove a time-dependent bias from the radiometer temperatures using data in clear air and adjust supersaturated dew points to the equivalent of 99 percent relative humidity. In contrast to previous studies, clear air is defined using dew point depression and aircraft roll rather than the absence of liquid water. The resulting radiometer temperatures and adjusted dew points are shown to be free of instrument wetting errors and accurate. Instrument wetting locations (IWL) are identified in roughly 50 percent of the radial legs, but are more frequent in intense (Category 3, 4, and 5) hurricanes than in minimal (Category 1 and 2) hurricanes and were comprised of larger temperature errors. The maximum temperature error, liquid water content, and radial extent of each IWL is highly variable, but the majority of IWL are located in cloudy updrafts associated with eyewall and rainband<l convection, and extend less than 15 km radially. Theoretical temperature errors are rarely achieved, however, average IWL temperature errors are significant and range with height from 1.0 to 4.5°C. The temperature errors, combined with average specific humidity (q) errors ranging from 1.0 to 2.0 g kg-1, result in virtual temperature (Tv) errors ranging from 1.5 to 5.0°C and equivalent potential temperature (Oe) errors ranging from 5 to 11 K. In the eyewall average temperature and specific humidity errors range with height from 0.5 - 2.0°C and 0.5 - 1.0 g kg-1 respectively. Errors of such magnitudes can have a significant effect upon thermodynamic calculations in a near convection. Various aspects of hurricane thermodynamics are thus re-examined. Radial composites about the eyewall Radius of Maximum Updraft (RMU) indicate that after instrument wetting errors are removed: the eyewall temperature is equivalent to 50-70 percent of the total anomaly observed from the environment; specific humidity maxima are located in the eyewall but are nearly equivalent to values in the eye; and eyewall Oe is 0-5 K lower than values in the eye. The composite eyewall is shown to be moist-adiabatic with height to a first approximation and better represented by pseudo-adiabatic, rather than reversible, ascent. Average eyewall Oe for minimal and intense hurricanes are 351 K and 360 K respectively, with maximum values near 385 K. Instrument wetting errors are shown to significantly affect calculations of thermal wind balance. Finally, surface temperatures and pressures are estimated beneath the eyewall. The ratio of eyewall surface pressure to minimum central pressure is 1.02 on average. The estimated average air-sea temperature difference (SST-Ta) beneath nearly-saturated eyewalls is 2°C with maximum values near 5°C. However, the air-sea temperature difference tends to decrease toward 1°C as hurricane intensity increases
Remote Sensing of Earth Resources: A literature survey with indexes (1970 - 1973 supplement). Section 1: Abstracts
Abstracts of reports, articles, and other documents introduced into the NASA scientific and technical information system between March 1970 and December 1973 are presented in the following areas: agriculture and forestry, environmental changes and cultural resources, geodesy and cartography, geology and mineral resources, oceanography and marine resources, hydrology and water management, data processing and distribution systems, instrumentation and sensors, and economic analysis