ASFPM responded to the request for comments on the U.S. Global Change Research Program’s proposed themes and framework for the Fifth National Climate Assessment (NCA5). As outlined in the Federal Register, NCA5 will include a number of overarching themes and perspectives that respond to needs and gaps identified by NCA4.
The following is a list of proposed themes for NCA5:
- Identification of advancements or improvements, relative to NCA4, in scientific understanding of human-induced and natural processes of global change and the resulting implications for the United States.
- Identification of vulnerable populations for climate-related risks and potential impacts, a theme highlighted in multiple previous assessments.
- Characterization of scientific uncertainties associated with key findings.
- Characterization of current and future risks associated with global change with quantifiable metrics, such as indicators, where possible, and with the needs of multiple audiences in mind.
- Emphasis on (1) near-term trends and projections that can inform adaptation needs; (2) long-term projections that are more scenario dependent; and (3) in some cases, timeframes past 2100, to be consistent with the GCRA and to indicate anticipated legacy effects of the human influence on the climate and oceans.
In its comments, ASFPM said it sees strong merit in the proposed themes and expressed concern about the lack of up-to-date information on expected frequencies of extreme precipitation events. In particular, ASFPM stressed the need for all Atlas 14 volumes to be updated every five years and recommended a study to identify an appropriate methodology to update the Probable Maximum Precipitation for the nation.
A number of other organizations submitted comments as well, including the Environmental and Energy Study Institute and the American Association for the Advancement of Science.