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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.

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At least 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

A Test of Functional Balance Theory for Wetland Biomass Allocation in a Global Change Experiment

Abstract Forecasts of root growth and carbon sequestration under global change are compromised by uncertainty in how plants will allocate biomass between above and belowground pools. Here, we develop a simple model to assess whether functional balance theory can explain a complex biomass allocation response observed in a brackish marsh under experimental warming and elevated CO 2 . Our model shows how treatment‐driven changes in nitrogen supply and demand can explain divergent observations of root growth (i.e., maximum responses under intermediate warming and elevated CO 2 ). The model also reveals a surprising interaction between warming and eutrophication, where enhanced N loading to coastal marshes may reduce adverse impacts of warming on root growth. Our findings provide a mechanistic basis for incorporating biomass allocation into forecast models of marsh evolution. They also provide a general example of using ecological theory to decompose complex net responses observed in multi‐factor global change experiments into constituent processes.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

Vegetation Type and Decomposition Priming Mediate Brackish Marsh Carbon Accumulation Under Interacting Facets of Global Change

Coastal wetland carbon pools are globally important, but their response to interacting facets of global change remain unclear. Numerical models neglect species-specific vegetation responses to sea level rise (SLR) and elevated CO 2 (eCO 2 ) that are observed in field experiments, while field experiments cannot address the long-term feedbacks between flooding and soil growth that models show are important. Here, we present a novel numerical model of marsh carbon accumulation parameterized with empirical observations from a long-running eCO 2 experiment in an organic rich, brackish marsh. Model results indicate that eCO 2 and SLR interact synergistically to increase soil carbon burial, driven by shifts in plant community composition and soil volume expansion. Furthermore, newly parameterized interactions between plant biomass and decomposition (i.e. soil priming) reduce the impact of eCO 2 on marsh survival, and by inference, the impact of eCO 2 on soil carbon accumulation.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS1989

Remote sensing of global change

Remote sensing instruments for monitoring global changes are examined. The use of the earth observing system, a set of instrument platforms in polar, sun-synchoronous orbit that provide coverage of the entire globe, is discussed. The radar and imaging spectrometers utilized to obtain surface measurements are described. Atmospheric data is collected by the atmospheric IR sounder, the tropospheric emission spectrometer, and the stratospheric wind IR limb sounder. Consideration is given to the operation of the microwave limb sounder, the active cavity radiometer, and the TDRSS.

Allen, Lew↗
DOE OSTI2022

Differential Response of Bacterial Microdiversity to Simulated Global Change

Microbial communities play an integral role in global biogeochemical cycling, but our understanding of how global change will affect microbial community structure and functioning remains limited. Microbiome analyses typically aggregate large amounts of genetic diversity which may obscure finer variation in traits.

59 BASIC BIOLOGICAL SCIENCES↗
NASA NTRS1991

Data principles for the U.S. Global Change Research Program

The U.S. Interagency Working Group on Data Management for Global Change has developed a set of data management and access principles. The overall purpose of these statements of principle is to stimulate responsible stewardship for data and related information and to facilitate full and open access to them. These statements have been accepted by the U.S. Agencies responsible for the Global Change Research Program. The statements of principle are presented and discussed.

Ludwig, George H.↗
DOE OSTI2021

The Implications of Global Change for the Co-Evolution of Argentina's Integrated Energy-Water-Land Systems

This study seeks to understand how Argentina’s energy, water, and land (EWL) systems will co-evolve under a representative array of human and earth system influences, including socioeconomic change, climate change, and climate policy. To capture Argentina’s sub-national EWL dynamics in the context of global change, we couple the Global Change Analysis Model with a suite of consistent, gridded sectoral downscaling models to explore multiple stakeholder-engaged scenarios. Across scenarios, Argentina has the economic opportunity to use its vast land resources to satisfy growing domestic and international demand for crops, such as oil (e.g., soy) and biomass. The human (rather than earth) system produces the most dominant changes in mid-century EWL resource use. A Reference scenario characterized by modest socioeconomic growth projects a 40% increase in Argentina’s agricultural production by 2050 (relative to 2020) by using 50,000 km 2 of additional cropland and 40% more water. A Climate Policy scenario designed to achieve net-zero carbon emissions globally shortly after mid-century projects that Argentina could use 100,000 km 2 of additional land (and 65% more water) to grow biomass and other crops. The burden of navigating these national opportunities and challenges could fall disproportionately on a subset of Argentina’s river basins. The Colorado and Negro basins could experience moderate-to-severe water scarcity as they simultaneously navigate substantial irrigated crop demand growth and climate-induced declines in natural water availability. Argentina serves as a generalizable testbed to demonstrate that multi-scale EWL planning challenges can be identified and managed more effectively via integrated analysis of coupled human-earth systems.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
NASA NTRS1991

Advanced technology needs for a global change science program: Perspective of the Langley Research Center

The focus of the NASA program in remote sensing is primarily the Earth system science and the monitoring of the Earth global changes. One of NASA's roles is the identification and development of advanced sensing techniques, operational spacecraft, and the many supporting technologies necessary to meet the stringent science requirements. Langley Research Center has identified the elements of its current and proposed advanced technology development program that are relevant to global change science according to three categories: sensors, spacecraft, and information system technologies. These technology proposals are presented as one-page synopses covering scope, objective, approach, readiness timeline, deliverables, and estimated funding. In addition, the global change science requirements and their measurement histories are briefly discussed.

Rowell, Lawrence F.↗
NASA NTRS1992

A global change data base using Thematic Mapper data - Earth Monitoring Educational System (EMES)

Some of the main directions in creating an education program in earth system science aimed at combining top science and technology with high academic performance are presented. The creation of an Earth Monitoring Educational System (EMES) integrated with the research interests of the NASA Ames Research Center and one or more universities is proposed. Based on the integration of a global network of cooperators to build a global data base for assessments of global change, EMES would promote degrees at all levels in global ecology at associated universities and colleges, and extracurricular courses for multilevel audiences. EMES objectives are to: train specialists; establish a tradition of solving regional problems concerning global change in a systemic manner, using remote sensing technology as the monitoring tool; and transfer knowledge on global change to the national and world communities. South America is proposed as the pilot continent for the project.

D'Antoni, Hector L.↗
NASA NTRS1992

The Role of Lidars in Global Change Research

Recent research has solidified a view of the Earth as a global scale interactive system with complex chemical, physical, biological, and dynamical processes that link the ocean, atmosphere, land, and marine terrestrial living organisms. An important aspect of Earth System Science studies in the future is the need to observe simultaneously the physical, chemical, biological, and dynamical processes involved in highly coupled phenomena such as those mentioned. Lidars operating from the surface, aircraft, and satellites provide a powerful observational technique to study the processes and observe trends important to global change. Lidar observations have already played important roles in helping understand processes controlling stratospheric ozone and aerosols, tropospheric clouds, water vapor, ozone, gaseous pollutants, and aerosols, and winds and temperatures throughout the atmosphere. In this paper the author reviews the science of global change and highlights the potential roles for lidar in studying the Earth system.

Prinn, Ronald G.↗
NASA NTRS2002

Global Change Research Related in the Earth's Energy and Hydrologic Cycle

The mission of the Global Change Research Related to the Earth's Energy and Hydrologic Cycle is to enhance the scientific knowledge and educational benefits obtained from NASA's Earth Science Enterprise and the U.S. Global Change Research Program, University of Alabama in Huntsville (UAH). This paper presents the final technical report on this collaborative effort. Various appendices include: A) Staff Travel Activities years one through three; B) Publications and Presentations years one through three; C) Education Activities; D) Students year one through three; E) Seminars year one through three; and F) Center for Applied Optics Projects.

Berry, Linda R.↗
NASA NTRS1997

The HSCaRS Summer Enrichment Program; Research Opportunities for Minority and Women Undergraduates in Global Change Science

The primary objective of the HSCaRS Summer Enrichment Program (SEP) is to make significant contributions to the NASA Mission to Planet Earth (MTPE) and the Alabama A&M University (AAMU) Center for Hydrology, Soil Climatology and Remote Sensing (HSCaRS) research missions by providing undergraduate student research internships with an emphasis on minority and women students. Additional objectives are to encourage more minority and women students to pursue advanced degrees in Earth system and global change science and to increase the participation of minority institutions in the U.S. Global Change Research Program. Also, the SEP strives to make students in the traditional science disciplines more aware of the opportunities in Earth System Science. In designing the SEP, it was acknowledged that HSCaRS was a new research effort and Center. Consequently, students were not expected to immediately recognize the Center as one would older, more established research laboratories with national reputations, such as Los Alamos, Battelle, National Consortium for Atmospheric Research (NCAR), etc. Yet we still wanted to compete nationally for the best students. Therefore, we designed the program with a competitive financial package that includes a stipend of $400 per week, round-trip transportation from home to the summer research site, and free campus housing and meal plans provided by Alabama A&M University. Students also received a modest living allowance of approximately $25 per week. The internship program was 10 weeks in residence at Alabama A&M University or IGCRE, and gave students the opportunity to select from six general research areas: micro-meteorology, soil data analysis, soil moisture modeling, instrumentation, geographic information systems, and computer science. Student participants also enrolled in an introductory global change science course as part of the summer program (a copy of the course outline is in the appendix). The program included participation in a field program for approximately two weeks. All students were required to participate in the field program as a learning experience, regardless of the relationship of the field program to their majors or particular research project.

Estes, Jr., Maurice G.↗
DOE OSTI2021

plutus: An R package to calculate electricity investments and stranded assets from the Global Change Analysis Model (GCAM)

plutus is an R package that post-processes outputs from the Global Change Analysis Model (GCAM) to calculate the power sector capital investment costs and stranded asset costs associated with GCAM projections of electricity generation by technology. GCAM is a market equilibrium model used to examine the dynamics of the coupled human-Earth system and the response of this system to global change, including socioeconomics, technology, climate, and policy. GCAM tracks electricity generation by technology and vintage over 32 geopolitical regions throughout the lifetime of each generating technology. plutus extends GCAM functionality by (1) estimating the foregone economic value of prematurely retired power plants as a result of economic-induced retirements compared to scheduled lifetimes; and (2) estimating the new installations and capital investments driven by future changes in economic, energy, agriculture, and land-use systems in GCAM.

97 MATHEMATICS AND COMPUTING↗
NASA NTRS1991

Hoop column soil moisture spacecraft in low Earth orbit for global change monitoring

A subset of the total Global Change Technology Initiative instruments are required to be in low Earth, sunsynchronous orbits. There is one instrument, however, that requires its own specialized spacecraft; the Soil Moisture Microwave Radiometer (SMMR). The characteristic structure of the instrument is the 118 m hoop column support structure. The hoop is supported by an axially placed column. Tension cables support and shape an electromagnetically reflective mesh surface. The instrument is capable of detecting frequencies in the 1.4 GHz range (Soil Moisture and Sea Salinity). Three apertures are used to reduce the degree of paraboloid offset and improve the beam quality. The spacecraft configuration is determined by the instrument support requirements and the requirement that it can fit into the Titan IV cargo bay. The configuration is derived by cross referencing the instrument performance requirements with the performance of the spacecraft. The spacecraft design is similar with the Multi-mission Modular Spacecraft in terms of size and packaging. A description of the spacecraft's features will yield a summary of the technologies needed for the SMMR spacecraft.

Ferebee, Melvin J., Jr.↗
NASA NTRS1991

SAGE III capabilities and global change

The science objectives of the satellite-borne SAGE III are presented as they pertain to detecting global change. SAGE III is the proposed follow on and improved version of SAM II, SAGE I and SAGE II which have measured stratospheric and, in some cases, tropospheric species since late 1978. Specifically, SAGE III will measure profiles of aerosols, ozone, water vapor, nitrogen dioxide and trioxide, neutral density, temperature, clouds, and chlorine dioxide using the solar and lunar occultation techniques. These techniques are inherently self-calibrating, provide high vertical resolution, and use well-behaved data retrievals making them ideal for trend detection and global change studies. The potential capabilities of SAGE III are illustrated by using data and results from SAM II, SAGE I and SAGE II.

Mccormick, M. Patrick↗
NASA NTRS2018

The Deep Space Gateway Lightning Mapper (DLM) - Monitoring Global Change and Thunderstorm Processes Through Observations of Earth's High-Latitude Lightning from Cis-Lunar Orbit

Function: Monitor global change and thunderstorm processes through observations of Earth's high-latitude lightning. This instrument will combine long-lived sampling of individual thunderstorms with long-term observations of lightning at high latitudes: How is global change affecting thunderstorm patterns; How do high-latitude thunderstorms differ from low-latitude? Why is the Gateway the optimal facility for this instrument / research: Expected DSG (Deep Space Gateway) orbits will provide nearly continuous viewing of the Earth's high latitudes (50 degrees latitude and poleward); These regions are not well covered by existing lightning mappers (e.g., Lightning Imaging Sensor / LIS, or Geostationary Lightning Mapper / GLM); Polar, Molniya, Tundra, etc. Earth orbits have significant drawbacks related to continuous coverage and/or stable FOVs (Fields of View).

Climate↗
NASA NTRS1994

Science priorities for the human dimensions of global change

The topics covered include the following: defining research needs; understanding land use change; improving policy analysis -- research on the decision-making process; designing policy instruments and institutions to address energy-related environmental problems; assessing impacts, vulnerability, and adaptation to global changes; and understanding population dynamics and global change.

Source record↗
NASA NTRSDate not supplied

NASA’s Global Change Master Directory (GCMD) Keyword Viewer Beta

The Global Change Master Directory (GCMD) Keyword Viewer is a web-based client that allows metadata curators and ontologists to search for and navigate the GCMD keywords in a user-friendly and human-readable tree structure. The Keyword Viewer is built on top of the Keyword Management Systems (KMS) API, which provides machine-to-machine access to the keywords.

Tyler B Stevens↗