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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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NASA NTRS1989

Climate change in the circum-North Atlantic region during the last deglaciation

A survey of new and published palaeoclimate data indicates that both the high- and low-latitude North Atlantic regions were characterized by at least three synchronous periods of abrupt climate change during the last glacial-to-interglacial transition. Climate model results suggest that changes in the melting history of the Laurentide Ice Sheet may explain much of this nonlinear response of the climate system to astronomical (Milankovitch) forcing.

Overpeck, Jonathan T.↗

NASA NTRSDate not supplied

Update and Status of the Mars Climate Modeling Center at NASA Ames Research Center

NASA Ames Research Center has a long-established history in the study and numerical modeling of Mars’ atmosphere and climate. Such studies began with the late Jim Pollack and have continued under the leaderships of Bob Haberle, Jeff Hollingsworth, and now Melinda Kahre. Our group has grown to more than 10 members, including civil servants, research scientists, postdocs, and students. While we still prioritize science and the model development that supports it, we have recently enhanced efforts to make our codes and output publicly available and boost community engagement through the hosting of modeling tutorials, etc. Here our goal is to present the status of the Ames Mars GCM, our ongoing science projects, the tools we have recently made publicly available, and our plans for releases and continued community engagement.

M. A. Kahre↗

DOE OSTI2023

Exploring Multiscale Earth System and Human-Earth System Dynamics in the Puget Sound Region

With its mountain-to-coast hydroclimate, strong influence of Pacific Ocean weather systems and climate patterns, and unique land use history with strong rural-to-urban gradients, the Puget Sound region is a natural laboratory for studying a number of complex processes in, and interactions among, different Earth and human systems. A 1-year scoping study was initiated by the Earth and Environmental Systems Modeling program of the Department of Energy’s Office of Science Biological and Environmental Research. It was intended to elucidate and highlight the rich opportunities Puget Sound offers to advance our understanding of and ability to simulate Earth system changes and human-Earth system interactions. A literature review, multi-day community workshop, and external input were used to develop this scoping study report. The report first summarizes scientific understanding and knowledge gaps associated with major regional systems, including atmosphere and climate, the land surface, coastal and marine processes, and human systems, as well as how these systems are changing over time. It then highlights some of the most notable extreme events in the region, including heat waves, atmospheric rivers, droughts, and wildfires. Finally, key research opportunities for Earth and environmental systems modeling in, above, and around Puget Sound are highlighted.

54 ENVIRONMENTAL SCIENCES↗

NASA NTRS2004

Lunar and Planetary Science XXXV: Special Session: Mars Climate Change

The session "Mars Climate Change" contained the following reports:Geological Evidence for Climate Change on Mars; A New Astronomical Solution for the Long Term Evolution of the Insolation Quantities of Mars; Interpreting Martian Paleoclimate with a Mars General Circulation Model; History and Progress of GCM Simulations on Recent Mars Climate Change; Northern and Southern Permafrost Regions on Mars with High Content of Water Ice: Similarities and Differences; Periods of Active Permafrost Layer Formation in the Recent Geological History of Mars; Microclimate Zones in the Dry Valleys of Antarctica: Implications for Landscape; Evolution and Climate Change on Mars; Geomorphic Evidence for Martian Ground Ice and Climate Change; Explaining the Mid-Latitude Ice Deposits with a General Circulation Model; Tharsis Montes Cold-based Glaciers: Observations and Constraints for Modeling and Preliminary Results; Ice Sheet Modeling: Terrestrial Background and Application to Arsia Mons Lobate Deposit, Mars; Enhanced Water-Equivalent Hydrogen on the Western Flanks of the Tharsis Montes and Olympus Mons: Remnant Subsurface Ice or Hydrate Minerals?; and New Age Mars.

Source record↗

NASA NTRS2004

Lunar and Planetary Science XXXV: Special Session: Mars Climate Change

The session "Mars Climate Change" included the following topics:Geological Evidence for Climate Change on Mars; A New Astronomical Solution for the Long Term Evolution of the Insolation Quantities of Mars; Interpreting Martian Paleoclimate with a Mars General Circulation Model; History and Progress of GCM Simulations on Recent Mars Climate Change; Northern and Southern Permafrost Regions on Mars with High Content of Water Ice: Similarities and Differences; Periods of Active Permafrost Layer Formation in the Recent Geological History of Mars; Microclimate Zones in the Dry Valleys of Antarctica: Implications for Landscape Evolution and Climate Change on Mars; Geomorphic Evidence for Martian Ground Ice and Climate Change; Explaining the Mid-Latitude Ice Deposits with a General Circulation Model; Tharsis Montes Cold-based Glaciers: Observations and Constraints for Modeling and Preliminary Results; Ice Sheet Modeling: Terrestrial Background and Application to Arsia Mons Lobate Deposit, Mars; Enhanced Water-Equivalent Hydrogen on the Western Flanks of the Tharsis Montes and Olympus Mons: Remnant Subsurface Ice or Hydrate Minerals?; and New Age Mars.

Source record↗

NASA NTRS2022

Economic incentives modify agricultural impacts of nuclear war

A nuclear war using less than 1% of the current global nuclear arsenal, which would inject 5 Tg of soot into the stratosphere, could produce climate change unprecedented in recorded human history and significant impacts on agricultural productivity and the economy. These effects would be most severe for the first five years after the nuclear war and may last for more than a decade. This paper calculates how food availability would change by employing the Environmental Impact and Sustainability Applied General Equilibrium model. Under a robust world trading system, global food availability would drop by a few percentage points. If the war would destabilize trade, it would magnify by several times the negative ramifications of land productivity shocks on food availability. If exporting countries redirect production to domestic consumption at the expense of importing countries, it would lead to the destabilization of international trade. The analysis suggests that economic models aiming to inform policymakers require both economic behavior analysis and biophysical drivers. Policy lessons derived from a crop model can be significantly nuanced when coupled with economic feedback derived from economic models. Through the impact on yield, farmers could shift production among crops and reallocate land use to maximize profits, showing the importance of general equilibrium effects such as product and input substitution and international trade. Although the global impact on corn and soybean production would be significant when just considering crop production, it could be considerably smaller under the economic model. However, this would be at the expense of other sectors, including livestock. In addition, the costs borne from disruptions to climate would vary significantly across regions, with significant adverse effects in high latitude regions. The severity of the shocks in the high-latitude areas would marginalize the farmers' product and input substitution ability.

Nuclear war↗

NASA NTRS2014

The Ancient Martian Climate System

Today Mars is a cold, dry, desert planet. The atmosphere is thin and liquid water is not stable at the surface. But there is evidence that very early in its history, some 3.7-4.1 billion years ago, the climate system supported much warmer conditions including an active hydrological cycle with rainfall and runoff. Given the importance of liquid water to astrobiology and NASA’s Mars Exploration Program, researchers have been trying to understand the ancient martian climate system since the early 1970s when the Mariner 9 spacecraft first detected fluvial features on its oldest terrains. Though the evidence for warm wet conditions is compelling, the problem is not yet solved. The main issue is coping with the faint young sun. During the period when warmer conditions prevailed the sun’s luminosity was ~25% less than it is today. How can we explain the presence of liquid water on the surface of ancient Mars under such conditions? A similar problem exists for Earth, which would have frozen over under a faint sun even though the evidence suggests otherwise. Attempts to solve the “Faint Young Sun Paradox”, as it is commonly known, rely on greenhouse warming from an atmosphere with a different mass and composition than we see today. This is true for both Mars and Earth. However, for Mars there is no solution in sight. Long-lived continuously warm and wet atmospheres are difficult to produce and sustain. And a new and emerging idea - that ancient Mars was fundamentally a cold planet with transient episodes of warm wet conditions brought about by external forcings such as impacts, volcanism, and/or orbital changes – also has issues. In this seminar I will review this fascinating topic and discuss some of the recent ideas on how to solve it, the issues they raise, and what I believe are some promising avenues for future research.

Haberle, Robert M.↗

DOE OSTI2023

Effects of Livestock Exclusion on Stream Habitat and Aquatic Biota: A Review and Recommendations for Implementation and Monitoring

Abstract To inform riparian restoration, research, and monitoring and to provide management recommendations, we reviewed published studies evaluating the physical and biological effectiveness of livestock exclusion and grazing reduction on various metrics in riparian and aquatic areas. We identified 95 North American studies that reported the effects of livestock grazing reduction on physical habitat (channel morphology, mesohabitats, substrate, and bank stability), biological assemblages (riparian vegetation, macroinvertebrates, fish, and birds), and water quality metrics (temperature, nitrates, phosphorus, and turbidity). Most studies reported that methods to reduce or exclude livestock decreased channel width, width-to-depth ratio, bank erosion, soil bulk density, bare ground, water temperature, nitrogen, and phosphorus and increased riparian vegetation (cover, height, productivity, biomass, and abundance), riparian bird abundance, and young-of-the-year fishes. Results for channel depth, instream substrate, mesohabitats, water depth, juvenile and adult fishes, and macroinvertebrates showed no consistent response to exclusion. Project success was influenced by the time since exclusion; whether there was complete exclusion or continued grazing; and local climate, geology, and soils. Apart from bank erosion and stability, most of the physical and biological metrics took more than a decade to respond to livestock exclusion. However, coupling exclusion with planting and other restoration measures decreased the recovery time. Complete exclusion of livestock produced more consistent improvements in riparian condition and other metrics than rest–rotation or other grazing management strategies. Understanding how physical and biological metrics respond to livestock exclusion will require (1) focused, long-term studies using before–after or before–after, control–impact designs; and (2) monitoring of metrics that most consistently respond to exclusion. Ultimately, the design of exclusions should be driven by local climate, geology, biophysical conditions, and management history. Our results highlight the need for watershed-scale approaches to excluding livestock from broad areas and the need for implementation monitoring to ensure that fencing and other exclusion measures continue to exclude livestock and produce the desired responses.

Krall, Michelle↗

NASA NTRS1988

Workshop on Mars Sample Return Science

Martian magnetic history; quarantine issues; surface modifying processes; climate and atmosphere; sampling sites and strategies; and life sciences were among the topics discussed.

Drake, Michael J.↗

NASA NTRS2011

Environmental Catastrophes in the Earth's History Due to Solar Systems Encounters with Giant Molecular Clouds

In its motion through the Milky Way galaxy, the solar system encounters an average density (>=330 H atoms/cubic cm) giant molecular cloud (GMC) approximately every 108 years, a dense (approx 2 x 103 H atoms/cubic cm) GMC every approx 109 years and will inevitably encounter them in the future. However, there have been no studies linking such events with severe (snowball) glaciations in Earth history. Here we show that dramatic climate change can be caused by interstellar dust accumulating in Earth's atmosphere during the solar system's immersion into a dense (approx ,2 x 103 H atoms/cubic cm) GMC. The stratospheric dust layer from such interstellar particles could provide enough radiative forcing to trigger the runaway ice-albedo feedback that results in global snowball glaciations. We also demonstrate that more frequent collisions with less dense GMCs could cause moderate ice ages.

Pavlov, Alexander A.↗

NASA NTRSDate not supplied

Can Large Scale Volcanism Explain the Heat-Death of Venus (and Venus-like worlds?)

One of the fundamental questions about Venus is whether it ever had a habitable period in its distant past. If it did have such a period how did Venus get from a temperate state to its present day hot-house? Recent studies have demonstrated that increasing solar luminosity through time is an unlikely pathway for Venus even if that is one way for Earth to end up in a runaway greenhouse state. Large Igneous Provinces (LIPs; like that of the Siberian Traps) have been responsible for the End Permian mass extinction and other dramatic climate change events throughout Earth’s history. We investigate the hypothesis that overlapping Large Igneous Provinces could have driven Venus from a temperate to a runaway greenhouse state. We look at the LIP record in Earth history and the probability for overlapping LIP events as a proxy.

Venus↗

NASA NTRS2016

Larch Forests of Middle Siberia: Long-Term Trends in Fire Return Intervals

Fire history within the northern larch forests of Central Siberia was studied (65+degN). Fires within this area are predominantly caused by lightning strikes rather than human activity. Mean fire return intervals (FRIs) were found to be 112 +/- 49 years (based on firescars) and 106 +/- 36 years (based on firescars and tree natality dates). FRIs were increased with latitude increase and observed to be about 80 years at 64N, about 200 years near the Arctic Circle and about 300 years nearby the northern range limit of larch stands (approx.71+degN). Northward FRIs increase correlated with incoming solar radiation (r = -0.95). Post- Little Ice Age (LIA) warming (after 1850) caused approximately a doubling of fire events (in comparison with a similar period during LIA). The data obtained support a hypothesis of climate-induced fire frequency increase. Keywords Fire ecology Fire history Fire frequency Siberian wildfires Larch forests Climate change

Fire ecology↗

NASA NTRS1992

Modeling Earth system changes of the past

This review outlines some of the challenging problems to be faced in understanding the causes and mechanisms of large climatic changes and gives examples of initial studies of these problems with climate models. The review covers climatic changes in three main periods of earth history: (1) the past several centuries; (2) the past several glacial-interglacial cycles; and (3) the past several million years. The review will concentrate on studies of climate but, where possible, will mention broader aspects of the earth system.

Kutzbach, John E.↗

NASA NTRS2005

The Effect of Impacts on the Martian Climate

Evidence for the presence of liquid water early in Mars history continues to accumulate. The most recent evidence for liquid water being pervasive early in Mars history is the discoveries of sulfate and gypsum layers by the Mars Exploration Rovers and Mars Express. However, the presence of liquid water at the surface very early in Mars history presents a conundrum. The early sun was most likely approximately 75% fainter than it is today. About 65-70 degrees of greenhouse warming is needed to bring surface temperatures to the melting point of water. To date climate models have not been able to produce a continuously warm and wet early Mars. This may be a good thing as there is morphological and mineralogical evidence that the warm and wet period had to be relatively short and episodic. The rates of erosion appear to correlate with the rate at which Mars was impacted thus an alternate possibility is transient warm and wet conditions initiated by large impacts. It is widely accepted that even relatively small impacts (approximately 10 km) have altered the past climate of Earth to such an extent as to cause mass extinctions. Mars has been impacted with a similar distribution of objects. The impact record at Mars is preserved in the abundance of observable craters on it surface. Impact induced climate change must have occurred on Mars.

Colaprete, A.↗

DOE OSTI2024

Technical Assistance Opportunities for Tribes

The National Renewable Energy Laboratory (NREL) offers many forms of technical assistance for Tribes to support local clean energy priorities and challenges. With broad support from the U.S. Department of Energy (DOE) and local partners, NREL provides technical expertise to enable data-driven, informed clean energy decision making. Technical assistance may address energy strategy, project financing, policy design and development, data analysis, economic development, infrastructure planning, energy justice, climate change, resilience, or other energy priorities. NREL has a long history of partnering with Tribes and Tribal organizations, including in Alaska Native Villages where the extreme Arctic climate poses unique energy challenges. NREL works directly with Tribes to find solutions that address their self-defined energy priorities, challenges, and goals.

Alaska native village↗

NASA NTRS1992

Orbital, rotational, and climatic interactions: Lessons from Earth and Mars

Though variations in orbital and rotational parameters of the Earth and Mars are widely recognized as plausible sources of significant climatic variation on 10(exp 3) to 10(exp 8) yr timescales, many aspects of the connection between orbital, rotational, and climatic variations remain poorly understood. In general, the orbital histories are very well known, the rotational histories (especially for Mars) are very poorly known. A brief review is given of recent progress in computing orbital and rotational secular variations, and in connecting them to climatic change. The emphasis is on highlighting those areas that limit the present understanding. It is obvious that mass redistributions associated with climatic change (glaciation) are a source of crustal deformation and geodynamic change on the Earth, and may have played similar roles on Mars. It is much less appreciated, that rates, phases, and amplitudes of deformation of the deep interior of the planet can influence climate. The mantle and core, if decoupled, would precess at different rates, and even with plausible coupling strengths, some degree of differential precession is possible.

Bills, Bruce G.↗

DOE OSTI2021

Chapter 6: Economic Development: Renewables, Sustainable Economies, & Carbon Offsets

This chapter reviews economic development issues and opportunities that Tribes face in the age of climate change. It includes summaries pertaining to Tribal histories and trauma, harmful federal policies and subsequent land tenure issues, and the surge of economic sovereignty through renewable energy development on Tribal lands, including carbon offset markets. Recommendations are offered to reinforce and expedite Tribal economic self-determination on Tribal lands in the context of climate change. The chapter opens with the narrative of the Ute Mountain Ute Tribe of southwest Colorado, describing how this Tribe developed a large-scale solar economic development project to reduce their Tribal energy bills and decrease their dependence on fossil fuel usage. A researched overview of Economic Development as it relates to Tribes and climate change follows these narratives, beginning with the Key Messages and Recommendation that the authors have identified.

climate change↗

NASA NTRS2015

Volcanic Eruptions and Climate

Volcanic eruptions represent some of the most climatically important and societally disruptive short-term events in human history. Large eruptions inject ash, dust, sulfurous gases (e.g. SO2, H2S), halogens (e.g. Hcl and Hbr), and water vapor into the Earth's atmosphere. Sulfurous emissions principally interact with the climate by converting into sulfate aerosols that reduce incoming solar radiation, warming the stratosphere and altering ozone creation, reducing global mean surface temperature, and suppressing the hydrological cycle. In this issue, we focus on the history, processes, and consequences of these large eruptions that inject enough material into the stratosphere to significantly affect the climate system. In terms of the changes wrought on the energy balance of the Earth System, these transient events can temporarily have a radiative forcing magnitude larger than the range of solar, greenhouse gas, and land use variability over the last millennium. In simulations as well as modern and paleoclimate observations, volcanic eruptions cause large inter-annual to decadal-scale changes in climate. Active debates persist concerning their role in longer-term (multi-decadal to centennial) modification of the Earth System, however.

Volcanoes↗