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NASA NTRS2002

STS-112 Flight Day 6 Highlights

On the sixth flight day of STS-112 (Atlantis crewmembers include Dave Wolf, Mission Specialists; Sandy Magnus, Mission Specialists; Pam Melroy, Pilot; Jeff Ashby, Commander; Piers Sellers, Mission Specialists; Fyodor Yurchikhin, Mission Specialists), Wolf and Sellers are seen preparing for an EVA (extravehicular activity) during which they will service the ISS (International Space Station) to which Atlantis is docked. This will be the 45th EVA in support of ISS assembly and maintenance and the 20th conducted from the ISS. While the astronauts prepare, video footage is shown of the Sahara desert, over which the ISS is passing in a track that will take it over North Africa and the Mediterranean Sea. During the EVA, the External Television Camera Group will be brought out of the station and attached to the station. As the astronauts work, their helmet mounted cameras provide excellent footage of the ISS with the Shuttle docked at the Destiny Laboratory Module. Multiple shots of the station show several modules including Destiny, Quest, Unity and Zarya, as well as Canadarm 2 and Atlantis. The video closes with a wide angle shot of the ISS.

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NASA NTRS2002

STS-109 Mission Highlights Resource Tape: Flight Days 8 - 12 - Part 4 of 4

This video, Part 4 of 4, shows footage of crew activities from flight days 8 through 12 of STS-109. The crew included: Scott Altman, Commander; Duane Carey, Pilot; John Grunsfeld, Payload Commander; Nancy Currie, Richard Linnehan, James Newman, Michael Massimino, Mission Speicalists. The activities from other flights days can be seen on 'STS-109 Mission Highlights Resource Tape' Part 1 of 4 (internal ID 2002139471), 'STS-109 Mission Highlights Resource Tape' Part 2 of 4 (internal ID 2002137664), and 'STS-109 Mission Highlights Resource Tape' Part 3 of 4 (internal ID 2002139476). The primary activity on flight day 8 was an EVA (extravehicular activity) by Grunsfeld and Linnehan to install a cryocooler and radiator for the NICMOS (Near Infrared Camera and Multi-Object Spectrometer) on the HST (Hubble Space Telescope). Before returning to Columbia's airlock, the astronauts, with a cloudy background, hold onto the orbiter and offer their thoughts on the significance of their mission, the HST, and spaceflight. Footage from flight day 9 includes the grappling, unbearthing, and deployment of the HST from Columbia, and the crew coordinating and videotaping Columbia's departure. Flight day 10 was a relatively inactive day, and flight day 11 includes a checkout of Columbia's aerodynamic surfaces. Columbia landed on flight day 12, which is covered by footage of the crew members speaking during reentry, and their night landing, primarily shown through the orbiter's head-up display. The video includes numerous views of the HST, as well as views of the the Galapagos Islands, Madagascar, and Southern Africa with parts of the Atlantic, Indian, and Pacific Oceans, and part of the coast of Chile. The pistol grip space tool is shown in use, and the crew answers two messages from the public, including a message to Massimino from the Fire Department of New York.

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NASA NTRS2002

STS-111 Mission Highlights Resource Tape: Flight Days 8 - 10 - Part 3 of 4

An overview of the STS-111 Endeavour mission is given through footage of each flight day. Scenes from flight days 8 through 10 show activities such as extravehicular activity (EVA) preparation, EVA activity to replace the wrist roll joint on the International Space Station's (ISS) robotic arm, logistics transfer operation, space suit check-out and loading of the Leonardo Multi-Purpose Logistics Module onto the Endeavour's cargo bay. Individual shots of Africa, Italy, Hispaniola, Mexico and the Strait of Gilbraltar are shown. For mission footage from flight days 1 to 7 and 11-14, see also, 'STS-111 Mission Highlights Resource Tape, Part 1', 'STS-111 Mission Highlights Resource Tape, Part 2' and 'STS-111 Mission Highlights Resource Tape, Part 4'.

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NASA NTRS2002

Ultramafic Terranes and Associated Springs as Analogs for Mars and Early Earth

Putative extinct or extant Martian organisms, like their terrestrial counterparts, must adopt metabolic strategies based on the environments in which they live. In order for organisms to derive metabolic energy from the natural environment (Martian or terrestrial), a state of thermodynamic disequilibrium must exist. The most widespread environment of chemical disequilibrium on present-day Earth results from the interaction of mafic rocks of the ocean crust with liquid water. Such environments were even more pervasive and important on the Archean Earth due to increased geothermal heat flow and the absence of widespread continental crust formation. The composition of the lower crust and upper mantle of the Earth is essentially the-same as that of Mars, and the early histories of these two planets are similar. It follows that a knowledge of the mineralogy, water-rock chemistry and microbial ecology of Earth's oceanic crust could be of great value in devising a search strategy for evidence of past or present life on Mars. In some tectonic regimes, cross-sections of lower oceanic crust and upper mantle are exposed on land as so-called "ophiolite suites." Such is the case in the state of California (USA) as a result of its location adjacent to active plate margins. These mafic and ultramafic rocks contain numerous springs that offer an easily accessible field laboratory for studying water/rock interactions and the microbial communities that are supported by the resulting geochemical energy. A preliminary screen of Archaean biodiversity was conducted in a cold spring located in a presently serpentinizing ultramafic terrane. PCR and phylogenetic analysis of partial 16s rRNA, sequences were performed on water and sediment samples. Archaea of recent phylogenetic origin were detected with sequences nearly identical to those of organisms living in ultra-high pH lakes of Africa.

Blake, David↗
NASA NTRS2002

HI-STAR. Health Improvements through Space Technologies and Resources: Executive Summary

Our mission is to develop and promote a global strategy to help combat malaria using space technology. Like the tiny yet powerful mosquito, HI-STAR (Health Improvements Through Space Technologies and Resources) is a small program that aspires to make a difference. Timely detection of malaria danger zones is essential to help health authorities and policy makers make decisions about how to manage limited resources for combating malaria. In 2001, the technical support network for prevention and control of malaria epidemics published a study. HI-STAR focuses on malaria because it is the most common and deadly of the vector-borne diseases. Malaria also shares many commonalities with other diseases, which means the global strategy developed here may also be applicable to other parasitic diseases. HI-STAR would like to contribute to the many malaria groups already making great strides in the fight against malaria. Some examples include: Roll Back Malaria, The Special Program for Research and Training in Tropical Diseases (TDR) and the Multilateral Initiative on Malaria (MIM). Other important groups that are among the first to include space technologies in their model include: The Center for Health Application of Aerospace Related Technologies (CHAART) and Mapping Malaria Risk in Africa (MARA). Malaria is a complex and multi-faceted disease. Combating it must therefore be equally versatile. HI-STAR incorporates an interdisciplinary, international, intercultural approach.called 'Malaria Early Warning Systems; Concepts, Indicators and Partners.' This study, funded by Roll Back Malaria, a World Health Organization initiative, offers a framework for a monitoring and early warning system. HI-STAR seeks to build on this proposal and enhance the space elements of the suggested framework. It is the work of fifty-three professionals and students from the International Space University's 2002 Summer Session Program held in California, USA.

Finarelli, Margaret G.↗
NASA NTRS2002

Vertical Profiles of Latent Heat Release over the Global Tropics using TRMM rainfall products from December 1997 to November 2001

NASA Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) derived rainfall information will be used to estimate the four-dimensional structure of global monthly latent heating and rainfall profiles over the global tropics from December 1997 to November 2001. Rainfall, latent heating and radar reflectivity structures between El Nino (DE 1997-98) and La Nina (DJF 1998-99) will be examined and compared. The seasonal variation of heating over various geographic locations (i.e., oceanic vs continental, Indian ocean vs. west Pacific, Africa vs. S. America) will also be analyzed. In addition, the relationship between rainfall, latent heating (maximum heating level), radar reflectivity and SST is examined and will be presented in the meeting. The impact of random error and bias in strtaiform percentage estimates from PR on latent heating profiles is studied and will also be presented in the meeting. The Goddard Cumulus Ensemble Model is being used to simulate various mesoscale convective systems that developed in different geographic locations. Specifically, the model estimated rainfall, radar reflectivity and latent heating profiles will be compared to observational data collected from TRMM field campaigns over the South China Sea in 1998 (SCSMEX), Brazil in 1999 (TRMM-LBA), and the central Pacific in 1999 (KWAJEX). Sounding diagnosed heating budgets and radar reflectivity from these experiments can provide the means to validate (heating product) as well as improve the GCE model.

Tao, W.-K.↗
NASA NTRS2002

Retrievals of Profiles of Fine And Coarse Aerosols Using Lidar And Radiometric Space Measurements

In couple of years we expect the launch of the CALIPSO lidar spaceborne mission designed to observe aerosols and clouds. CALIPSO will collect profiles of the lidar attenuated backscattering coefficients in two spectral wavelengths (0.53 and 1.06 microns). Observations are provided along the track of the satellite around the globe from pole to pole. The attenuated backscattering coefficients are sensitive to the vertical distribution of aerosol particles, their shape and size. However the information is insufficient to be mapped into unique aerosol physical properties and vertical distribution. Infinite number of physical solutions can reconstruct the same two wavelength backscattered profile measured from space. CALIPSO will fly in formation with the Aqua satellite and the MODIS spectro-radiometer on board. Spectral radiances measured by MODIS in six channels between 0.55 and 2.13 microns simultaneously with the CALIPSO observations can constrain the solutions and resolve this ambiguity, albeit under some assumptions. In this paper we describe the inversion method and apply it to aircraft lidar and MODIS data collected over a dust storm off the coast of West Africa during the SHADE experiment. It is shown that the product of the single scattering albedo, omega, and the phase function, P, for backscattering can be retrieved from the synergism between measurements avoiding a priori hypotheses required for inverting lidar measurements alone. The resultant value of (omega)P(180 deg.) = 0.016/sr are significantly different from what is expected using Mie theory, but are in good agreement with recent results obtained from lidar observations of dust episodes. The inversion is robust in the presence of noise of 10% and 20% in the lidar signal in the 0.53 and 1.06 pm channels respectively. Calibration errors of the lidar of 5 to 10% can cause an error in optical thickness of 20 to 40% respectively in the tested cases. The lidar calibration errors cause degradation in the ability to fit the MODIS data. Therefore the MODIS measurements can be used to identify the calibration problem and correct for it. The CALIPSO-MODIS measurements of the profiles of fine and coarse aerosols, together with CALIPSO measurements of clouds vertical distribution, is expected to be critically important in understanding aerosol transport across continents and political boundaries, and to study aerosol-cloud interaction and its effect on precipitation and global forcing of climate.

Kaufman, Yoram↗
NASA NTRS2003

Predicting the Structure of the Solar Corona During the December 4, 2002 Total Solar Eclipse

The solar magnetic field plays a key role in determining coronal. The principal input to MHD models is the observed solar magnetic field. 3D MHD models can be used to compare with eclipse and coronograph images, SOHO images (LOSCO, EIT), Ulysses and WIND spacecraft data, and interplanetary scintillation (IPS) measurements. MHD computations can tell us about the structure of the corona. Eclipses can help us to verify the accuracy of the models. 4 December, 2002 total eclipce: visible in the southern hemisphere (South Atlantic, southern Africa, Indian Ocean, and Australia). Total in center Angola is at 06:00 UT.

Mikic, Zoran↗
NASA NTRS2003

Tropospheric Ozone Over the North Pacific from Ozonesdonde Observations

As part of the TRACE-P mission, ozone vertical profile measurements were made at a number of locations in the North Pacific. At most of the sites there is also a multi-year record of ozonesonde observations. From seven locations in the western Pacific (Hong Kong; Taipei; Jeju Island, Korea; and Naha, Kagoshima, Tsukuba, and Sapporo, Japan), a site in the central Pacific (Hilo, HI), and a site on the west coast of the U.S. (Trinidad Head, CA) both a seasonal and event specific picture of tropospheric ozone over the North Pacific emerges. At all of the sites there is a pronounced spring maximum through the troposphere. There are, however, differences in the timing and strength of this feature. Over Japan the northward movement of the jet during the spring and summer influences the timing of the seasonal maximum. The ozone profiles suggest that transport of ozone rich air from the stratosphere plays a strong role in the development of this maximum. During March and April at Hong Kong ozone is enhanced in a layer that extends from the lower free troposphere into the upper troposphere that likely has its origin in biomass burning in northern Southeast Asia and equatorial Africa. During the winter the Pacific subtropical sites (latitude -25N) are dominated by air with a low-latitude, marine source that gives low ozone amounts particularly in the upper troposphere. In the summer in the boundary layer at all of the sites marine air dominates and ozone amounts are generally quite low (less than 25 ppb). The exception is near large population centers (Tokyo and Taipei but not Hong Kong) where pollution events can give amounts in excess of 80 ppb. During the TRACE-P intensive campaign period (February-April 2001) tropospheric ozone amounts were rather typical of those seen in the long-term records of the stations with multi-year soundings.

Oltmans, S. J.↗
NASA NTRS2002

Remote Sensing of Suspended Sediments and Shallow Coastal Waters

Ocean color sensors were designed mainly for remote sensing of chlorophyll concentrations over the clear open oceanic areas (case 1 water) using channels between 0.4 and 0.86 micrometers. The Moderate Resolution Imaging Spectroradiometer (MODIS) launched on the NASA Terra and Aqua Spacecrafts is equipped with narrow channels located within a wider wavelength range between 0.4 and 2.5 micrometers for a variety of remote sensing applications. The wide spectral range can provide improved capabilities for remote sensing of the more complex and turbid coastal waters (case 2 water) and for improved atmospheric corrections for Ocean scenes. In this article, we describe an empirical algorithm that uses this wide spectral range to identifying areas with suspended sediments in turbid waters and shallow waters with bottom reflections. The algorithm takes advantage of the strong water absorption at wavelengths longer than 1 micrometer that does not allow illumination of sediments in the water or a shallow ocean floor. MODIS data acquired over the east coast of China, west coast of Africa, Arabian Sea, Mississippi Delta, and west coast of Florida are used in this study.

Li, Rong-Rong↗
NASA NTRS2003

Insights into Tropical Tropospheric Ozone from Satellite and Sonde Data

The first climatological overview of total, stratospheric and tropospheric ozone in the southern hemisphere tropical and subtropics is based on ozone sounding data from 10 sites comprising the Southern Hemisphere Additional OZonesondes (SHADOZ) network. Observations were made over: Ascension Island; Nairobi, Kenya; Irene, South Africa; Reunion Island; Watukosek, Java; Fiji; Tahiti; American Samoa; San Cristobal, Galapagos; Natal, Brazil. The data reside at: http://code916.gsfc.nasa.gov/Data_services/shadoz. SHADOZ ozone time-series and profiles give a perspective on tropical total, stratospheric and tropospheric ozone. Prominent features are highly variable tropospheric ozone and a zonal wave-one pattern in total (and tropospheric) column ozone. Dynamical and chemical influences appear to be of comparable magnitude though model studies are needed to quantify this. In addition to leading the SHADOZ network, we have been producing near-real tropical tropospheric ozone ('TTO') data from the Total Ozone Mapping Spectrometer (TOMS) since 1997 with Prof. Hudson and students at the University of Maryland: http://metosrv2.umd.edu/~tropo. Further perspective on the complexity of tropospheric ozone variability is shown using satellite observations.

Thompson, Anne M.↗
NASA NTRS2003

Numerical simulation of the geographical sources of water for Continental Scale Experiments (CSEs) Precipitation

There are several important research questions that the Global Energy and Water Cycle Experiment (GEWEX) is actively pursuing, namely: What is the intensity of the water cycle and how does it change? And what is the sustainability of water resources? Much of the research to address these questions is directed at understanding the atmospheric water cycle. In this paper, we have used a new diagnostic tool, called Water Vapor Tracers (WVTs), to quantify the how much precipitation originated as continental or oceanic evaporation. This shows how long water can remain in the atmosphere and how far it can travel. The model-simulated data are analyzed over regions of interest to the GEWEX community, specifically, their Continental Scale Experiments (CSEs) that are in place in the United States, Europe, Asia, Brazil, Africa and Canada. The paper presents quantitative data on how much each continent and ocean on Earth supplies water for each CSE. Furthermore, the analysis also shows the seasonal variation of the water sources. For example, in the United States, summertime precipitation is dominated by continental (land surface) sources of water, while wintertime precipitation is dominated by the Pacific Ocean sources of water. We also analyze the residence time of water in the atmosphere. The new diagnostic shows a longer residence time for water (9.2 days) than more traditional estimates (7.5 days). We emphasize that the results are based on model simulations and they depend on the model s veracity. However, there are many potential uses for the new diagnostic tool in understanding weather processes and large and small scales.

Bosilovich, Michael G.↗
NASA NTRS2003

Discoveries about Tropical Tropospheric Ozone from Satellite and SHADOZ (Southern Hemisphere Additional Ozonesondes) and a Future Perspective on NASA's Ozone Sensors

We have been producing near-real tropical tropospheric ozone ('TTO') data from TOMS since 1997 with Prof. Hudson and students at the University of Maryland. Maps for 1996-2000 for the operational Earth-Probe instrument reside at: . We also have archived 'TTO' data from the Nimbus 7/TOMS satellite (1979-1992). The tropics is a region strongly influenced by natural variability and anthropogenic activity and the satellite data have been used to track biomass burning pollution and to detect interannual variability and climate signals in ozone. We look forward to future ozone sensors from NASA; four will be launched in 2004 as part of the EOS AURA Mission. The satellite view of chemical-dynamical interactions in tropospheric ozone is not adequate to capture vertical variability. Thus, in 1998, NASA's Goddard Space Flight Center, NOAA's Climate Monitoring and Diagnostics Laboratory (CMDL) and a team of international sponsors established the SHADOZ (Southern Hemisphere ADditional OZonesondes) project to address the gap in tropical ozone soundings. SHADOZ augments launches at selected sites and provides a public archive of ozonesonde data from twelve tropical and subtropical stations at http://croc.nsfc.nasa.gov/shadoz. The stations are: Ascension Island; Nairobi, Kenya; Irene, South Africa; R,union Island; Watukosek, Java; Fiji; Tahiti; American Samoa; San Cristobal, Galapagos; Natal, Brazil, Malindi, Kenya; Paramaribo, Surinam. From the first 3-4 years of data (presently greater than 1700 sondes), the following features emerge: (a) highly variable tropospheric ozone; (b) a zonal wave-one pattern in tropospheric column ozone; (c) tropospheric ozone variability over the Indian and Pacific Ocean displays strong convective signatures.

Thompson, Anne↗
NASA NTRS2003

Global Vertical Rates from VLBl

The analysis of global VLBI observations provides vertical rates for 50 sites with formal errors less than 2 mm/yr and median formal error of 0.4 mm/yr. These sites are largely in Europe and North America with a few others in east Asia, Australia, South America and South Africa. The time interval of observations is up to 20 years. The error of the velocity reference frame is less than 0.5 mm/yr, but results from several sites with observations from more than one antenna suggest that the estimated vertical rates may have temporal variations or non-geophysical components. Comparisons with GPS rates and corresponding site position time series will be discussed.

Ma, Chopo↗
NASA NTRS2003

Ozone Pollution, Transport and Variability: Examples from Satellite and In-Situ Observations

Regional and intercontinental transport of ozone has been observed from satellite, aircraft and sounding data. Over the past several years, we have developed new tropospheric ozone retrieval techniques from the TOMS (Total Ozone Mapping Spectrometer) satellite instrument that are of sufficient resolution to follow pollution episodes. The modified-residual technique uses Level 2 total ozone and was used to follow the 1997 fires in the wake of the El-Nino-related fires in southeast Asia and the Indonesian maritime continent. The TOMS-direct method ('TDOT' = TOMS Direct Ozone in the Troposphere) is a newer algorithm that uses TOMS radiances directly to extract tropospheric ozone. Ozonesonde data that have been taken in campaigns (e.g. TRACE-P) and more consistently in the SHADOZ (Southern Hemisphere Additional Ozonesondes) project, reveal layers of pollution traceable with trajectories. Examples will be shown of long-range transport and recirculation over Africa during SAFARI-2000.

Thompson, Anne↗
NASA NTRS2003

Calculations of Aerosol Radiative Forcing in the SAFARI Region from MODIS Data

SAFARI 2000 provided the opportunity to validate MODIS aerosol retrievals and to correct any assumptions in the retrieval process. By comparing MODIS retrievals with ground-based sunphotometer data, we quantified the degree to which the MODIS algorithm underestimated the aerosol optical thickness. This discrepancy was attributed to underestimating the degree of light absorption by the southern African smoke aerosol. Correcting for this underestimation of absorption, produces more realistic aerosol retrievals that allow various applications of the MODIS aerosol products. One such application is the calculation of the aerosol radiative forcing at the top and bottom of the atmosphere. The combination of MODIS accuracy, coverage, resolution and the ability to separate fine and coarse mode make this calculation substantially advanced over previous attempts with other satellites. We focus on the oceans adjacent to southern Africa and use a solar radiative transfer model to perform the flux calculations. The forcing at the top of atmosphere is calculated to be 10 W/sq m, while the forcing at the surface is -26 W/sq m. These results resemble those calculated from INDOEX data, and are most sensitive to assumptions of aerosol absorption, the same parameter that initially interfered with our retrievals.

Remer, L. A.↗
NASA NTRS2000

Early Archean Spherule Beds-Confirmation of Impact Origin

The oldest record of major impact events on Earth may be a number of early Archean (3.5 to 3.2 Ga) spherule beds that have been identified in the Barberton Greenstone Belt, South Africa. Several field, petrographic, and geochemical criteria distinguish these beds from typical volcanic and clastic sediments. These criteria include the wide geographic distribution of two beds in a variety of depositional environments, the presence of relict quench textures, absence of juvenile volcaniclastic debris within the beds, and extreme enrichment of Ir and other platinum group elements (PGE) as compared to surrounding sediments. Some researchers, however, argued for a terrestrial origin for spherule bed formation, possibly related to volcanism and gold mineralization.

Shukolyukov, A.↗
NASA NTRS2003

Early Archean Spherule Beds: Chromium Isotopes Confirm Origin Through Multiple Impacts of Projectiles of Carbonaceous Chondrite Type

Three Early Archean spherule beds from Barberton, South Africa, have anomalous Cr isotope compositions in addition to large Ir anomalies, confirming the presence of meteoritic material with a composition similar to that in carbonaceous chondrites. The extra-terrestrial components in beds S2, S3, and S4 are estimated to be approx. l%, 50% - 60%, and 15% - 30%, respectively. These beds are probably the distal, and possibly global, ejecta from major large-body impacts. These impacts were probably much larger than the Cretaceous-Tertiary event, and all occurred over an interval of approx. 20 m.y., implying an impactor flux at 3.2 Ga that was more than an order of magnitude greater than the present flux.

Kyte, Frank T.↗