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Abstracts and tutorial are presented from the workshop. Representative titles are: Geology of Southern Guinevere Planitia, Venus, Based on Analyses of Goldstone Radar Data; Tessera Terrain: Characteristics and Models of Origin; Venus Volcanism; Rate Estimates from Laboratory Studies of Sulfur Gas-Solid Reactions; and A Morphologic Study of Venus Ridge Belts.
Various topics related to cases of difficult adaptation to global change are discussed. Topics include patterns in the ratification of global environmental treaties, the effects of global climate change on Southeast Asia, and global change and biodiversity loss.
The general theme for the workshop revolved around global environmental change. Over 170 individuals participated in the presentations and ensuing discussions about the many agency activities using airborne platforms and sensors in support of the U.S. Global Change Research Program (GCRP). The U.S. GCRP was developed as a central component of the U.S. Government's approach to global change and its contribution to worldwide efforts. An all-encompassing U.S. plan was developed by the Committee on Earth and Environmental Sciences (CEES), which continues as the interagency coordinating group for the program. The U.S. GCRP was established as a Presidential initiative in the FY90 budget, making it a particularly relevant topic for the workshop. The following are presented in the appendices: (1) final agenda and list of registrants; (2) final list of poster presenters; (3) steering group luncheon participants; (4) the draft resolution; and (5) selected handouts.
The focus of the workshop was on how the airborne community can assist in achieving the goals of the Global Change Research Program. The many activities that employ airborne platforms and sensors were discussed: platforms and instrument development; airborne oceanography; lidar research; SAR measurements; Doppler radar; laser measurements; cloud physics; airborne experiments; airborne microwave measurements; and airborne data collection.
The papers presented at the symposium focus on global monitoring of the earth with emphasis on the solution of environmental problems and utilization of natural resources. Topics discussed include radar forestry modeling, hydrological remote sensing, polarimetric SAR observations of sea ice, optical and IR oceanography, and satellite remote sensing of precipitation and related phenomena. Other subject areas covered are microwave sensing of trace gases; atmospheric pressure, temperature, and humidity; spaceborne sensor technology; geodynamic and geophysical remote sensing; space radar missions; remote sensing of vegetation and crops; and remote sensing of weather systems.
The general task was to look beyond the adverse physical impacts and to defining the policy problem. In order for policy actions to be effective, they must address the right policy problems, which will be different from and broader than the physical problems. We will work on defining the policy problems with a view to indicating how practical solutions might be implemented. In particular, public officials need advice on what should be said, and done, and for what purposes. That advice needs to be based on systematic analysis of: (1) the scholarly literature in the social sciences, and related disciplines; (2) the charging content of the policy debate at the center of attention; and (3) how citizens perceive and understand issues related to global change. We will conduct this analysis. Chapter 1 and 2 each reports work on defining the policy problem and analyzing the scholarly literature. Chapters 3 and 4, respectively, address the policy debate and citizen viewpoints in issues related to global change.
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The papers presented at the symposium focus on remote sensing, particularly on global monitoring of the earth with emphasis on the solution of environmental problems. Topics discussed include remote sensing of clouds and earth troposphere, sea ice remote sensing, optical remote sensing, land monitoring and thermal sensing, atmospheric sounding and monitoring, atmospheric correction, and satellite imaging data. Other subject areas are ecosystems and vegetation monitoring; ocean winds and surface scattering; ocean waves, currents and bathymetry; satellite oceanography; SAR for remote sensing; neural nets application to remote sensing; geographical information systems; and electromagnetic wave propagation. Also discussed environmental monitoring using ERS-1; Topex/Poseidon results; spaceborne instruments; image processing and classification algorithms; and future space missions.
This document discusses such areas as: atmosphere, synthetic aperture radar, marine/ocean, sea ice, soil, crustal movements/vegetation, geophysical modeling, electromagnetic problems, etc.
The objectives of this proposal were: (1) to assemble the existing spacecraft thermal-infrared data and to place these data into a uniform format as specified by the PDS; (2) to develop a standardized software package, user interface, and catalog database to support the access and analysis of existing and planned thermal infrared datasets in order to provide wide community access to these data; (3) to support the distribution of Thermal SubNode data to users as requested; (4) to incorporate future spacecraft thermal observations into the Thermal SubNode; and (5) to sponsor workshops on the applications of Thermal SubNode data.
This report, which represents the results of the workshop, is divided into two sections. Section I includes an executive summary, a chapter introducing the reader to GPS and its usefulness for Earth, oceanic, and atmospheric research, and four chapters summarizing the themes of the workshop presentations, poster papers, and working group discussions. Section II contains the proceedings of the workshop and is divided into five chapters corresponding to the five categories of invited papers written by workshop speakers and authors of poster papers. The appendices contain additional information about the workshop and the Steering Committee.
GLAS is a space-based lidar designed for NASA's Earth Science Enterprise's Icesat Mission. It is being designed to precisely measure the heights of the polar ice sheets, to determine the height profiles of the Earth's land topography, and to profile the vertical structure of clouds and aerosols on a global scale. GLAS will fly on a small dedicated spacecraft in a polar orbit at 598 km altitude with an inclination of 94 degrees. The instrument is being developed to launch in July 2001 and to operate continuously at 40 Hz for a minimum of 3 years with a goal of 5 years.
An octet of microsatellites to be launched in 2003 promises to deliver a large amount of useful data for meteorological, climatic, ionospheric, and geodetic research as well as for operational weather forecasting and space weather monitoring. Known as the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC), the joint Taiwan-U.S. scientific satellite project makes use of Global Positioning System (GPS) occultation and tracking signals. COSMIC's final operational configuration is depicted in Figure 1. Each of the eight microsatellites in low-Earth-orbit (LEO, shown relative to the high-altitude GPS satellite orbits) will carry in particular an advanced limb-sounding GPS receiver, a Tiny Ionospheric Photometer, and a triband beacon transmitter.
Accurate measurements of surface heights and atmospheric backscatter have been demonstrated with the SLA, MOLA and LITE space lidar. Recent MOLA measurements of the Mars surface have 40 cm resolution and have reduced the global uncertainty in Mars topography from a few km to approx. 10 m. GLAS is a next generation lidar being developed as part of NASA's Icesat Mission for Earth orbit . The GLAS design combines a 10 cm precision surface lidar with a sensitive dual wavelength cloud and aerosol lidar. GLAS will precisely measure the heights of the Earth's polar ice sheets, determine the height profiles of the Earth's land topography, and profile the vertical backscatter of clouds and aerosols on a global scale. GLAS will fly on a small dedicated spacecraft in a polar orbit at 598 km altitude with an inclination of 94 degrees. GLAS is scheduled to launch in summer 2001 and to operate continuously for a minimum of 3 years with a goal of 5 years. The primary mission for GLAS is to measure the seasonal and annual changes in the heights of the Greenland and Antarctic ice sheets. GLAS will measure the vertical distance to the ice sheet from orbit with 1064 nm pulses from a Nd:Yag laser at 40 Hz. Each 5 nsec wide laser pulse is used for a single range measurement. When over land GLAS will profile the heights of the topography and vegetation. The GLAS receiver uses a I m diameter telescope and a Si APD detector. The detector signal is sampled by an all digital receiver which records each surface echo waveform with I nsec resolution and a stored echo record lengths of either 200, 400, or 600 samples. Analysis of the echo waveforms within the instrument permits discrimination between cloud and surface echoes. Ground based echo analysis permits precise ranging, determining the roughness or slopes of the surface as well as the vertical distributions of vegetation illuminated by the laser, Errors in knowledge of the laser beam pointing angle can bias height measurements of sloped surfaces. For surfaces with 2 deg. slopes, knowledge of pointing angle of the beam centroid to about 8 urad is required to achieve 10 cm height accuracy. GLAS uses a stellar reference system (SRS) to determine the pointing angle of each laser firing relative to inertial space. The SRS uses a high precision star camera oriented toward local zenith whose measurements are combined with a gyroscope to determine the inertial orientation of the SRS optical bench. The far field pattern of each laser pulse is measured with a laser reference system (LRS). Optically measuring each laser far field pattern relative to the star camera and gyroscope permits the angular offsets of each laser pulse to be determined. GLAS will also determine the vertical distributions of clouds and aerosols by measuring atmospheric backscatter profiles at both 1064 and 532 nm. The 1064 nm measurements use an analog detector and profile the height and vertical structure of thicker clouds. Measurements at 532 nm use new highly sensitive photon counting detectors, and measure the height distributions of very thin clouds and aerosol layers. With averaging these can be used to determine the height of the planetary boundary layer. The instrument design and expected performance will be discussed.
EventScope is an educational software application that incorporates Mars mission data to teach geologic and scientific concepts using 3D (three-dimensional) models of planetary surfaces. It serves as a supplement to middle school science curricula. Additional information is contained in the original extended abstract.
The importance of oceanic impacts of collisional events and resulting energy release, are briefly described. Data collection methods from the Eltanin (a mesosiderite projectile) deep water impact, are presented.
Polar Stratospheric Clouds (PSCs) frequently occur in the polar regions during winter and are important because they play a role in the destruction of stratospheric ozone. During late September and early October 2003, GLAS frequently observed PSCs over western Antarctica. At the peak of this activity on September 29 and 30 we investigate the vertical structure and extent, horizontal coverage and backscatter characteristics of the PSCs using the GLAS data. The PSCs were found to cover an area approximately 10 to 15 % of the size of Antarctica in a region where enhanced PSC frequency has been noted by previous PSC climatology studies. The area of PSC formation was found to coincide with the coldest temperatures in the lower stratosphere. In addition, extensive cloudiness was seen within the troposphere below the PSCs indicating that tropospheric disturbances might have played a role in their formation.
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