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Meyer, R.

Publications and source records attributed to Meyer, R..

11 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

A Framework for Sustained Climate Assessment in the United States

The recent Fourth National Climate Assessment (NCA4) (USGCRP 2017a, 2018a) shows that extensive changes in climate have been observed in all regions of the country. The report states that climate change “creates new risks and exacerbates existing vulnerabilities…presenting growing challenges to human health and safety, quality of life, and the rate of economic growth.” And it concludes that without additional large reductions in emissions, “substantial net damage to the US economy [will occur] throughout this century…” As a result of growing public concern (Leiserowitz et al. 2018), efforts to reduce human contributions to climate change (“mitigation”) and to adjust systems and practices to uncertain future climate conditions (“adaptation”) are gaining traction. These efforts notwithstanding, multiple assessments have concluded that mitigation is not taking place nearly rapidly enough to stabilize atmospheric GHG concentrations at safe levels (e.g., IPCC 2014, 2018). Assessments of the state of adaptation have found that adaptation is progressing, but not fast enough (e.g., Hansen et al. 2012; Bierbaum et al. 2014; Vogel et al. 2016). Finally, practitioners are making long-term plans and investments without consideration of future climate changes and impacts likely to affect the lives and livelihoods of U.S. citizens.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2019

Evaluating Knowledge to Support Climate Action: A Framework for Sustained Assessment. Report of an Independent Advisory Committee on Applied Climate Assessment

As states, cities, tribes, and private interests cope with climate damages and seek to increase preparedness and resilience, they will need to navigate myriad choices and options available to them. Making these choices in ways that identify pathways for climate action that support their development objectives will require constructive public dialogue, community participation, and flexible and ongoing access to science- and experience-based knowledge. In 2016, a Federal Advisory Committee (FAC) was convened to recommend how to conduct a sustained National Climate Assessment (NCA) to increase the relevance and usability of assessments for informing action. The FAC was disbanded in 2017, but members and additional experts reconvened to complete the report that is presented here. A key recommendation is establishing a new nonfederal ‘‘climate assessment consortium’’ to increase the role of state/local/tribal government and civil society in assessments. The expanded process would 1) focus on applied problems faced by practitioners, 2) organize sustained partnerships for collaborative learning across similar projects and case studies to identify effective tested practices, and 3) assess and improve knowledge-based methods for project implementation. Specific recommendations include evaluating climate models and data using user-defined metrics; improving benefit–cost assessment and supporting decision-making under uncertainty; and accelerating application of tools and methods such as citizen science, artificial intelligence, indicators, and geospatial analysis. The recommendations are the result of broad consultation and present an ambitious agenda for federal agencies, state/local/tribal jurisdictions, universities and the research sector, professional associations, nongovernmental and community-based organizations, and private-sector firms.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS1976

Shuttle/TDRSS Ku-band downlink study

Assessing the adequacy of the baseline signal design approach, developing performance specifications for the return link hardware, and performing detailed design and parameter optimization tasks was accomplished by completing five specific study tasks. The results of these tasks show that the basic signal structure design is sound and that the goals can be met. Constraints placed on return link hardware by this structure allow reasonable specifications to be written so that no extreme technical risk areas in equipment design are foreseen. A third channel can be added to the PM mode without seriously degrading the other services. The feasibility of using only a PM mode was shown to exist, however, this will require use of some digital TV transmission techniques. Each task and its results are summarized.

Meyer, R.↗
NASA NTRS1973

An analytical procedure for evaluating shuttle abort staging aerodynamic characteristics

An engineering analysis and computer code (AERSEP) for predicting Space Shuttle Orbiter - HO Tank longitudinal aerodynamic characteristics during abort separation has been developed. Computed results are applicable at Mach numbers above 2 for angle-of-attack between plus or minus 10 degrees. No practical restrictions on orbiter-tank relative positioning are indicated for tank-under-orbiter configurations. Input data requirements and computer running times are minimal facilitating program use for parametric studies, test planning, and trajectory analysis. In a majority of cases AERSEP Orbiter-Tank interference predictions are as accurate as state-of-the-art estimates for interference-free or isolated-vehicle configurations. AERSEP isolated-orbiter predictions also show excellent correlation with data.

Meyer, R.↗