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NASA NTRS2005

Lunar and Planetary Science XXXVI, Part 14

Contents include the following: Destruction of Presolar Silicates by Aqueous Alteration Observed in Murchison CM2 Chondrite. Generation of Chondrule Forming Shock Waves in Solar Nebula by X-Ray Flares. TEM and NanoSIMS Study of Hydrated/Anhydrous Phase Mixed IDPs: Cometary or Asteroidal Origin? Inflight Calibration of Asteroid Multiband Imaging Camera Onboard Hayabusa: Preliminary Results. Corundum and Corundum-Hibonite Grains Discovered by Cathodoluminescence in the Matrix of Acfer 094 Meteorite. Spatial Extent of a Deep Moonquake Nest A Preliminary Report of Reexamination. Modal Abundances of Carbon in Ureilites: Implications for the Petrogenesis of Ureilites. Trapped Noble Gas Components and Exposure History of the Enstatite Chondrite ALH84206. Deep-seated Crustal Material in Dhofar Lunar Meteorites: Evidence from Pyroxene Chemistry. Numerical Investigations of Kuiper Belt Binaries. Dust Devils on Mars: Effects of Surface Roughness on Particle Threshold. Hecates Tholus, Mars: Nighttime Aeolian Activity Suggested by Thermal Images and Mesoscale Atmospheric Model Simulations. Are the Apollo 14 High-Al Basalts Really Impact Melts? Garnet in the Lunar Mantle: Further Evidence from Volcanic Glass Beads. The Earth/Mars Dichotomy in Mg/Si and Al/Si Ratios: Is It Real? Dissecting the Polar Asymmetry in the Non-Condensable Gas Enhancement on Mars: A Numerical Modeling Study. Cassini VIMS Preliminary Exploration of Titan s Surface Hemispheric Albedo Dichotomy. An Improved Instrument for Investigating Planetary Regolith Microstructure. Isotopic Composition of Oxygen in Lunar Zircons Preliminary Design of Visualization Tool for Hayabusa Operation. Size and Shape Distributions of Chondrules and Metal Grains Revealed by X-Ray Computed Tomography Data. Properties of Permanently Shadowed Regolith. Landslides in Interior Layered Deposits, Valles Marineris, Mars: Effects of Water and Ground Shaking on Slope Stability. Mars: Recent and Episodic Volcanic, Hydrothermal, and Glacial Activity Revealed by Mars Express High Resolution Stereo Camera (HRSC). The Cratering Record of the Saturnian Satellites Phoebe, Tethys, Dione and Iapetus in Comparison: First Results from Analysis of the Cassini ISS Imaging Data. Joint Crossover Solutions of Altimetry and Image Data on 433 Eros. The Martian Soil as a Geochemical Sink for.

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NASA NTRS2005

Moonshine Versus Earthshine: Physics Makes a Difference

Introduction: Recently released, high-resolution images from the Mars Orbiter Camera (MOC) and the Thermal Emission Imaging System (THEMIS) reveal a myriad of intriguing landforms banked along the northern edge of Terby Crater located on the northern rim of Hellas (approx.28degS, 287degW). Landforms within this crater include north-trending troughs and ridges, a remarkable 2.5 km-thick sequence of exposed layers, mantled ramps that extend across and between layered sequences, fan-like structures, sinuous channels, collapse pits, a massive landslide and viscous flow features. The suite of diverse landforms in Terby and its immediate surroundings attest to a diversity of rock types and geologic processes, making this locality ideal for studying landform-climate relationships on Mars. In order to decipher the complicated geologic history of Terby Crater and the nature of the layered deposits, a generalized geomorphic map was created and the slope of the layered deposits was examined.

Wilson, T. L.↗

NASA NTRS2005

Characterization of Layered Deposits inside Valles Marineris

This report represents the final progress report on our study of the Melas Chasma region on Mars that was proposed as a landing site for the Mars Exploration Rover mission (MER). During this two-year proposal (which was extended over three years by a no-cost extension), we conducted a thorough study of the layered deposits in western Melas Chasma that had been the location of a high priority MER mission landing ellipse within Valles Marineris. All available data sets from orbiter missions, including MOC, MOLA, THEMIS visible and infrared images were all used to analyze this site. The major outcome of this work was a published paper in the Journal of Geophysics and Research Planets [Weitz et al., 2004]. Our geologic mapping and interpretation of the MOC images suggest the landing ellipse contains three main geomorphologic units: (1) a blocky deposit consisting of bright blocks in a darker matrix (BD); (2) sand sheets composed of dark dunes; and (3) landslide deposits emanating from the wallrock to the west [Weitz et al., 2003]. Furthermore, we propose that the morphology of the BD unit in western Melas is a mass wasting deposit composed of blocks of Interior Layered Deposits (ILDs) mixed in with wallrock material. However, more recent MOC images indicate that in the eastern portion of the ellipse and adjacent to a large hill, there are blocks of material resembling those seen in BD. Hence, we cannot rule out the source of BD was this hill. Unfortunately, sand dunes obscure much of the deposit around this hill, making it impossible to precisely determine the connection between the hill and BD, whereas BD can be traced directly to the southern Melas wallrock. If BD resulted from a mass wasting event in the southern wallrock, then we would expect the material to be concentrated further to the north, as now appears to be the case. In summary, the exact source location for BD continues to remain a mystery, but we favor an origin from either the southern wallrock [Weitz et el., 2002] or the eastern hill.

Weitz, Catherine↗

NASA NTRS2006

Precipitation Measurements from Space: Why Do We Need Them?

Water is fundamental to the life on Earth and its phase transition between the gaseous, liquid, and solid states dominates the behavior of the weather/climate/ecological system. Precipitation, which converts atmospheric water vapor into rain and snow, is central to the global water cycle. It regulates the global energy balance through interactions with clouds and water vapor (the primary greenhouse gas), and also shapes global winds and dynamic transport through latent heat release. Surface precipitation affects soil moisture, ocean salinity, and land hydrology, thus linking fast atmospheric processes to the slower components of the climate system. Precipitation is also the primary source of freshwater in the world, which is facing an emerging freshwater crisis in many regions. Accurate and timely knowledge of global precipitation is essential for understanding the behavior of the global water cycle, improving freshwater management, and advancing predictive capabilities of high-impact weather events such as hurricanes, floods, droughts, and landslides. With limited rainfall networks on land and the impracticality of making extensive rainfall measurements over oceans, a comprehensive description of the space and time variability of global precipitation can only be achieved from the vantage point of space. This presentation will examine current capabilities in space-borne rainfall measurements, highlight scientific and practical benefits derived from these observations to date, and provide an overview of the multi-national Global Precipitation Measurement (GPM) Mission scheduled to be launched in the early next decade.

Hou, Arthur Y.↗

NASA NTRS2007

Precipitation Measurements from Space: The Global Precipitation Measurement Mission

Hou, Arthur Y.↗

NASA NTRS2007

TRMM's Contribution to Our Knowledge of Climatology, Storms and Floods

The Tropical Rainfall Measuring Mission (TRMM) has successfully completed nearly ten years in orbit. A brief review of the history and accomplishments of this joint mission between the U.S. and Japan is presented. Research highlights will focus on the seasonal cycle of a TRMM-based rainfall climatology, which takes advantage of the multiple rain estimates available from TRMM. Examples will be given of the use of TRMM data to diagnose the impact of man on precipitation patterns through urbanization and the effect of pollution. Use of TRMM data for tropical cyclone operational analysis in the U.S. will also be shown. Methods for generating 3-hourly rainfall information from multiple satellites using TRMM to calibrate all the information will be described as will application of such information to study extreme rainfall events and associated floods and landslides. These results will emphasize the breadth of science success achieved with the 10-year record of observations from the only rain radar and passive microwave instrument combination in space. The outlook for continued operation of the TRMM satellite and progress in TRMM science and applications will be addressed.

Adler, Robert↗

NASA NTRS2008

Assessing the Relative Performance of Microwave-based Satellite Rain Rate Retrievals using TRMM Ground Validation Data

Space-borne microwave sensors provide critical rain information used in several global multi-satellite rain products, which in turn are used for a variety of important studies, including landslide forecasting, flash flood warning, data assimilation, climate studies, and validation of model forecast of precipitation. This study employs four years (2003-2006) of satellite data to assess the relative performance and skill of SSM/I (F13, F14 and F15), AMSU-B (N15, N16 and N17), AMSR-E (AQUA) and the TRMM Microwave Imager (TMI) in estimating surface rainfall based on direct instantaneous comparison with ground-based rain estimates from Tropical Rainfall Measuring Mission (TRMM) Ground Validation (GV) sites at Kwajalein, Republic of the Marshall Islands (KWAJ) and Melbourne, Florida (MELB). The relative performance of each of these satellites is examined via comparisons with GV radar-based rain rate estimates. Because underlying surface terrain is known to affect the relative performance of the satellite algorithms, the data for MELB was further stratified into ocean, land and coast categories using a 0.25 terrain mask. Of all the satellite estimates compared in this study, TMI and AMSR-E exhibited considerably higher correlations and skills in estimating/observing surface precipitation. While SSM/I and AMSU-B exhibited lower correlations and skills for each of the different terrain categories, the SSM/I absolute biases trended slightly lower than AMSRE over ocean, where the observations from both emission and scattering channels were used in the retrievals. AMSU-B exhibited the least skill relative to GV in all of the relevant statistical categories, and an anomalous spike was observed in the probability distribution functions near 1.0 mm hr-1. This statistical artifact appears to be related to attempts by algorithm developers to include some lighter rain rates, not easily detectable by its scatter-only frequencies. AMSU-B, however, agreed well with GV when the matching data was analyzed on monthly scales. These results signal developers of global rainfall products, such as the TRMM Multi-Satellite Precipitation Analysis (TMPA), and the Climate Data Center s Morphing (CMORPH) technique, that care must be taken when incorporating data from these input satellite estimates in order to provide the highest quality estimates in their products.

Wolff, David B.↗

NASA NTRS2008

Onboard Data Processor for Change-Detection Radar Imaging

A computer system denoted a change-detection onboard processor (CDOP) is being developed as a means of processing the digitized output of a synthetic-aperture radar (SAR) apparatus aboard an aircraft or spacecraft to generate images showing changes that have occurred in the terrain below between repeat passes of the aircraft or spacecraft over the terrain. When fully developed, the CDOP is intended to be capable of generating SAR images and/or SAR differential interferograms in nearly real time. The CDOP is expected to be especially useful for understanding some large-scale natural phenomena and/or mitigating natural hazards: For example, it could be used for near-real-time observation of surface changes caused by floods, landslides, forest fires, volcanic eruptions, earthquakes, glaciers, and sea ice movements. It could also be used to observe such longer-term surface changes as those associated with growth of vegetation (relevant to estimation of wildfire fuel loads). The CDOP is, essentially, an interferometric SAR processor designed to operate aboard a radar platform.

Lou, Yunling↗

NASA NTRS2009

The Urban Environmental Monitoring/100 Cities Project: Legacy of the First Phase and Next Steps

The Urban Environmental Monitoring (UEM) project, now known as the 100 Cities Project, at Arizona State University (ASU) is a baseline effort to collect and analyze remotely sensed data for 100 urban centers worldwide. Our overarching goal is to use remote sensing technology to better understand the consequences of rapid urbanization through advanced biophysical measurements, classification methods, and modeling, which can then be used to inform public policy and planning. Urbanization represents one of the most significant alterations that humankind has made to the surface of the earth. In the early 20th century, there were less than 20 cities in the world with populations exceeding 1 million; today, there are more than 400. The consequences of urbanization include the transformation of land surfaces from undisturbed natural environments to land that supports different forms of human activity, including agriculture, residential, commercial, industrial, and infrastructure such as roads and other types of transportation. Each of these land transformations has impacted, to varying degrees, the local climatology, hydrology, geology, and biota that predate human settlement. It is essential that we document, to the best of our ability, the nature of land transformations and the consequences to the existing environment. The focus in the UEM project since its inception has been on rapid urbanization. Rapid urbanization is occurring in hundreds of cities worldwide as population increases and people migrate from rural communities to urban centers in search of employment and a better quality of life. The unintended consequences of rapid urbanization have the potential to cause serious harm to the environment, to human life, and to the resulting built environment because rapid development constrains and rushes decision making. Such rapid decision making can result in poor planning, ineffective policies, and decisions that harm the environment and the quality of human life. Slower, more thought-out, decision making could result in more favorable outcomes. The harm to the environment includes poor air quality, soil erosion, polluted rivers and aquifers, and loss of wildlife habitat. Human life is then threatened because of increased potential for disease spreading, human conflict, environmental hazards, and diminished quality of life. The built environment is potentially threatened when cities are built in areas that can be impacted by events such as hurricanes, tsunamis, earthquakes, fires, and landslides. Our goals include assessing the threat of such events on cities and the people living there.

Stefanov, William L.↗

NASA NTRS2009

Sequential Imaging of Earth by Astronauts: 50 Years of Global Change

For nearly 50 years, astronauts have collected sequential imagery of the Earth. In fact, the collection of astronaut photography comprises one of the earliest sets of data (1961 to present) available to scientists to study the regional context of the Earth s surface and how it changes. While today s availability of global high resolution satellite imagery enables anyone with an internet connection to examine specific features on the Earth s surface with a regional context, historical satellite imagery adds another dimension (time) that provides researchers and students insight about the features and processes of a region. For example, one of the geographic areas with the longest length of record contained within the astronaut photography database is the lower Nile River. The database contains images that document the flooding of Lake Nasser (an analog to today s flooding behind China s Three Gorges Dam), the changing levels of Lake Nasser s water with multiyear cycles of flood and drought, the recent flooding and drying of the Toshka Lakes, as well as urban growth, changes in agriculture and coastal subsidence. The imagery database allows investigations using different time scales (hours to decades) and spatial scales (resolutions and fields of view) as variables. To continue the imagery collection, the astronauts on the International Space Station are trained to understand basic the Earth Sciences and look for and photograph major events such as tropical storms, landslides, and volcanic eruptions, and document landscapes undergoing change (e.g., coastal systems, cities, changing forest cover). We present examples of selected sequences of astronaut imagery that illustrate the interdependence of geological processes, climate cycles, human geography and development, and prompt additional questions about the underlying elements of change.

Evans, Cynthia A.↗

NASA NTRS2010

The Global Precipitation Measurement (GPM) Project

The Global Precipitation Measurement (GP!v1) mission is an international cooperative effort to advance the understanding of the physics of the Earth's water and energy cycle. Accurate and timely knowledge of global precipitation is essential for understanding the weather/climate/ecological system, for improving our ability to manage freshwater resources, and for predicting high-impact natural hazard events including floods, droughts, extreme weather events, and landslides. The GPM Core Observatory will be a reference standard to uniformly calibrate data from a constellation of spacecraft with passive microwave sensors. GPM is being developed under a partnership between the United States (US) National Aeronautics and Space Administration (NASA) and the Japanese Aerospace and Exploration Agency (JAXA). NASA's Goddard Space Flight Center (GSFC), in Greenbelt, MD is developing the Core Observatory, two GPM Microwave Imager (GMI) instruments, Ground Validation System and Precipitation Processing System for the GPM mission. JAXA will provide a Dual-frequency Precipitation Radar (DPR) for installation on the Core satellite and launch services for the Core Observatory. The second GMI instrument will be flown on a partner-provided spacecraft. Other US agencies and international partners contribute to the GPM mission by providing precipitation measurements obtained from their own spacecraft and/or providing ground-based precipitation measurements to support ground validation activities. The Precipitation Processing System will provide standard data products for the mission.

Azarbarzin, Ardeshir↗

NASA NTRS2010

Progress in Development of the Axel Rovers

Progress has been made in the development of a family of robotic land vehicles having modular and minimalist design features chosen to impart a combination of robustness, reliability, and versatility. These vehicles at earlier stages of development were described in two previous NASA Tech Briefs articles: "Reconfigurable Exploratory Robotic Vehicles" (NPO-20944), Vol. 25, No. 7 (July 2001), page 56; and "More About Reconfigurable Exploratory Robotic Vehicles" (NPO-30890), Vol. 33, No. 8 (August 2009), page 40. Conceived for use in exploration of the surfaces of Mars and other remote planets, these vehicles could also be adapted to terrestrial applications, including exploration of volcanic craters or other hostile terrain, military reconnaissance, inspection of hazardous sites, and searching for victims of earthquakes, landslides, avalanches, or mining accidents. In addition, simplified versions of these vehicles might be marketable as toys. The most basic module in this family of reconfigurable robots is the Axel rover, which has a cylindrical body with two main wheels and a trailing link. Inside its body are three motors and associated mechanisms for driving the two wheels and for rotating the link 360 around its symmetrical body. The actuated link serves several purposes: It is used as a lever arm to react to the wheels thrust to move Axel in multiple directions. It is used to rotate the Axel housing in order to tilt, to the desired angle, any sensors and instruments mounted on or in the Axel housing. It provides an alternative mobility mode, which is primarily used in its tethered configuration. Turn ing the link into the ground in lieu of driving the wheels causes the Axel housing and wheels to roll as a unit and thereby leads to a tumbling motion along the ground. With a tether mounted around Axel s cylindrical body, the link serves as a winch mechanism to reel and unreel the tether raising and lowering Axel over steep and vertical surfaces (Figure 1). Sensors, computation, and communication modules are also housed inside Axel s body. A pair of stereo vision cameras provides three-dimensional view for autonomous navigation and avoiding obstacles. Inertial sensors determine the tilt of the robot and are used for estimating its motion. In a fully developed version, power would be supplied by rechargeable batteries aboard Axel; at the time of reporting the information for this article, power was supplied from an external source via a cable. In and of itself, the Axel rover is fully capable of traversing and sampling terrains on planetary surfaces. By use of only the two main wheel actuators and the caster link actuator, Axel can be made to follow an arbitrary path, turn in place, and operate upside- down or right-side-up. If operated in a tethered configuration, as shown in Figure 1, it can be made to move down and up a steep crater wall, descend from an overhang to a cave, and ascend from the cave back to the overhang, all by use of the same three actuators. Such tethered operation could be useful in searching for accident victims or missing persons in mines, caves, and rubble piles. Running the tether through the caster link enhances the stability of Axel and provides a restoring force that keeps the link off the ground for the most part during operation on a steep slope. In its extended configuration, two Axel modules can dock to either side of a payload module to form the four wheeled Axel2 rover (Figure 2). Additional payload and Axel modules can dock to either side of the Axel2 to form the Axel3 rover, extending its payload capacity and its mobility capabilities.

Nesnas, Issa A.↗

NASA NTRS2010

Assessing the Relative Performance of Microwave-Based Satellite Rain Rate Retrievals Using TRMM Ground Validation Data

Space-borne microwave sensors provide critical rain information used in several global multi-satellite rain products, which in turn are used for a variety of important studies, including landslide forecasting, flash flood warning, data assimilation, climate studies, and validation of model forecasts of precipitation. This study employs four years (2003-2006) of satellite data to assess the relative performance and skill of SSM/I (F13, F14 and F15), AMSU-B (N15, N16 and N17), AMSR-E (Aqua) and the TRMM Microwave Imager (TMI) in estimating surface rainfall based on direct instantaneous comparisons with ground-based rain estimates from Tropical Rainfall Measuring Mission (TRMM) Ground Validation (GV) sites at Kwajalein, Republic of the Marshall Islands (KWAJ) and Melbourne, Florida (MELB). The relative performance of each of these satellite estimates is examined via comparisons with space- and time-coincident GV radar-based rain rate estimates. Because underlying surface terrain is known to affect the relative performance of the satellite algorithms, the data for MELB was further stratified into ocean, land and coast categories using a 0.25 terrain mask. Of all the satellite estimates compared in this study, TMI and AMSR-E exhibited considerably higher correlations and skills in estimating/observing surface precipitation. While SSM/I and AMSU-B exhibited lower correlations and skills for each of the different terrain categories, the SSM/I absolute biases trended slightly lower than AMSRE over ocean, where the observations from both emission and scattering channels were used in the retrievals. AMSU-B exhibited the least skill relative to GV in all of the relevant statistical categories, and an anomalous spike was observed in the probability distribution functions near 1.0 mm/hr. This statistical artifact appears to be related to attempts by algorithm developers to include some lighter rain rates, not easily detectable by its scatter-only frequencies. AMSU-B, however, agreed well with GV when the matching data was analyzed on monthly scales. These results signal developers of global rainfall products, such as the TRMM Multi-Satellite Precipitation Analysis (TMPA), and the Climate Data Center s Morphing (CMORPH) technique, that care must be taken when incorporating data from these input satellite estimates in order to provide the highest quality estimates in their products. 3

Wolff, David B.↗

NASA NTRS2010

World, We Have Problems: Simulation for Large Complex, Risky Projects, and Events

Prior to a spacewalk during the NASA STS/129 mission in November 2009, Columbia Broadcasting System (CBS) correspondent William Harwood reported astronauts, "were awakened again", as they had been the day previously. Fearing something not properly connected was causing a leak, the crew, both on the ground and in space, stopped and checked everything. The alarm proved false. The crew did complete its work ahead of schedule, but the incident reminds us that correctly connecting hundreds and thousands of entities, subsystems and systems, finding leaks, loosening stuck valves, and adding replacements to very large complex systems over time does not occur magically. Everywhere major projects present similar pressures. Lives are at - risk. Responsibility is heavy. Large natural and human-created disasters introduce parallel difficulties as people work across boundaries their countries, disciplines, languages, and cultures with known immediate dangers as well as the unexpected. NASA has long accepted that when humans have to go where humans cannot go that simulation is the sole solution. The Agency uses simulation to achieve consensus, reduce ambiguity and uncertainty, understand problems, make decisions, support design, do planning and troubleshooting, as well as for operations, training, testing, and evaluation. Simulation is at the heart of all such complex systems, products, projects, programs, and events. Difficult, hazardous short and, especially, long-term activities have a persistent need for simulation from the first insight into a possibly workable idea or answer until the final report perhaps beyond our lifetime is put in the archive. With simulation we create a common mental model, try-out breakdowns of machinery or teamwork, and find opportunity for improvement. Lifecycle simulation proves to be increasingly important as risks and consequences intensify. Across the world, disasters are increasing. We anticipate more of them, as the results of global warming prove more and more ominous-glaciers melting in Bolivia, floods in Saudi Arabia, the Maldives sinking and salt rising along the Nile. Fear grows about potential asteroid crashes and nightly television images raise awareness of victims of floods, hurricanes, cyclones and typhoons, fire, tornado, tsunami, bombings, landslides, and cross-boundary criminality. The Red Cross says that disasters impact 250 million people each year. That means that 700,000 people are having a very bad day today. Modeling and simulation is and must be part of the solution.

Elfrey, Priscilla↗

NASA NTRS2010

What if Things Get Worse? Really Grand Challenges for Modeling and Simulation in a Risky and Complex World or Modeling and Simulation for the "Greater Good"?

Today Modeling and Simulation-- ---as an important practice or industry or area of expertise ----- is at a complex crossroad - a sort of cyber-highway--where these complexities meet-technical, economic, environmental, geopolitical and cultural. They may converge or collide. Let's not kid ourselves. It is all too much for anyone person or organization Malcolm Gladwell said it. "We have constructed a world in which the potential for high tech catastrophe is embedded in the fabric of everyday life." We are surrounded by problems that scream at us from our television, Internet and social networks along with billboards and protest signs. We face not just high tech catastrophes but, also, landslides, earthquakes, tornados, floods and hurricanes and large-scale criminality. Evil, war, famine and pestilence have not gone away. It is all too much to think about. My friend, George Peabody, who taught me everything I know about power said that addressing such issues requires that we constantly build our network, information resources and the credibility and visibility of our work. That is how we will build the power of simulation so it can change the world --even maybe, save it. We need all the help we can get and give one another because our human early warning systems appear to be out of kilter. We seem to have trouble imagining how small failings can continue to lead to catastrophic disaster. Think about O-rings and blowout preventers. One is reminded of the old nursery rhyme, "For want of a nail, a shoe was lost! for want of a shoe the horse was lost! for want of a rider the battle was lost and so the kingdom fell." Although the investigation will take more time for real answers, it is worrisome that a rig worker reported to the BBC that-- weeks before the explosion of Deep Ocean Horizon. -he identified a leak in the oil rig's safety equipment -the Control Pod of the blowout preventer which has giant shears designed to cut and seal off the well's main pipe. With both electronics and hydraulics, these are effectively the brains of the blowout preventer. No one fixed it, he alleges, they just shut it down and relied on the other control pod -an act deemed unacceptable by petroleum expert, Tad Patzek, at the University of Texas. The US Congress has identified numerous other problems with the blowout preventer, including design problems and unexpected modifications.

Fifrey, Priscilla↗

NASA NTRS2010

Proposed Use of the NASA Ames Nebula Cloud Computing Platform for Numerical Weather Prediction and the Distribution of High Resolution Satellite Imagery

The development of the Nebula Cloud Computing Platform at NASA Ames Research Center provides an open-source solution for the deployment of scalable computing and storage capabilities relevant to the execution of real-time weather forecasts and the distribution of high resolution satellite data to the operational weather community. Two projects at Marshall Space Flight Center may benefit from use of the Nebula system. The NASA Short-term Prediction Research and Transition (SPoRT) Center facilitates the use of unique NASA satellite data and research capabilities in the operational weather community by providing datasets relevant to numerical weather prediction, and satellite data sets useful in weather analysis. SERVIR provides satellite data products for decision support, emphasizing environmental threats such as wildfires, floods, landslides, and other hazards, with interests in numerical weather prediction in support of disaster response. The Weather Research and Forecast (WRF) model Environmental Modeling System (WRF-EMS) has been configured for Nebula cloud computing use via the creation of a disk image and deployment of repeated instances. Given the available infrastructure within Nebula and the "infrastructure as a service" concept, the system appears well-suited for the rapid deployment of additional forecast models over different domains, in response to real-time research applications or disaster response. Future investigations into Nebula capabilities will focus on the development of a web mapping server and load balancing configuration to support the distribution of high resolution satellite data sets to users within the National Weather Service and international partners of SERVIR.

Limaye, Ashutosh S.↗

NASA NTRS2011

Assessing the Relative Performance of Microwave-Based Satellite Rain Rate Retrievals Using TRMM Ground Validation Data

Space-borne microwave sensors provide critical rain information used in several global multi-satellite rain products, which in turn are used for a variety of important studies, including landslide forecasting, flash flood warning, data assimilation, climate studies, and validation of model forecasts of precipitation. This study employs four years (2003-2006) of satellite data to assess the relative performance and skill of SSM/I (F13, F14 and F15), AMSU-B (N15, N16 and N17), AMSR-E (Aqua) and the TRMM Microwave Imager (TMI) in estimating surface rainfall based on direct instantaneous comparisons with ground-based rain estimates from Tropical Rainfall Measuring Mission (TRMM) Ground Validation (GV) sites at Kwajalein, Republic of the Marshall Islands (KWAJ) and Melbourne, Florida (MELB). The relative performance of each of these satellite estimates is examined via comparisons with space- and time-coincident GV radar-based rain rate estimates. Because underlying surface terrain is known to affect the relative performance of the satellite algorithms, the data for MELB was further stratified into ocean, land and coast categories using a 0.25deg terrain mask. Of all the satellite estimates compared in this study, TMI and AMSR-E exhibited considerably higher correlations and skills in estimating/observing surface precipitation. While SSM/I and AMSU-B exhibited lower correlations and skills for each of the different terrain categories, the SSM/I absolute biases trended slightly lower than AMSR-E over ocean, where the observations from both emission and scattering channels were used in the retrievals. AMSU-B exhibited the least skill relative to GV in all of the relevant statistical categories, and an anomalous spike was observed in the probability distribution functions near 1.0 mm/hr. This statistical artifact appears to be related to attempts by algorithm developers to include some lighter rain rates, not easily detectable by its scatter-only frequencies. AMSU-B, however, agreed well with GV when the matching data was analyzed on monthly scales. These results signal developers of global rainfall products, such as the TRMM Multi-Satellite Precipitation Analysis (TMPA), and the Climate Data Center s Morphing (CMORPH) technique, that care must be taken when incorporating data from these input satellite estimates in order to provide the highest quality estimates in their products.

Wolff, David B.↗

NASA NTRS2010

SERVIR: The Regional Visualization and Monitoring System

This slide presentation reviews the SERVIR program. SERVIR is a partnership between NASA and USAID and three international nodes: Central America, Africa, and the Himalaya region. SERVIR,using satellite observations and ground based observations, is used by decision makers to allow for improved monitoring of air quality, extreme weather, biodiversity, and changes in land cove and has also been used to respond to environmental threats, such as wildfires, floods, landslides, harmful algal blooms, and earthquakes.

Irwin, Daniel E.↗