finding 22.1 : key-message-22-1

Water is the lifeblood of the Northern Great Plains, and effective water management is critical to the region’s people, crops and livestock, ecosystems, and energy industry. Even small changes in annual precipitation can have large effects downstream (very high confidence); when coupled with the variability from extreme events, these changes make managing these resources a challenge (very high confidence). Future changes in precipitation patterns, warmer temperatures, and the potential for more extreme rainfall events are very likely to exacerbate these challenges (very likely, high confidence).

This finding is from chapter 22 of Impacts, Risks, and Adaptation in the United States: The Fourth National Climate Assessment, Volume II.

Process for developing key messages:

The chapter lead (CL) and coordinating lead author (CLA) developed a list of potential contributing authors by soliciting suggestions from the past National Climate Assessment (NCA) author team, colleagues and collaborators throughout the region, and contributors to other regional reports. Our initial list of potential authors also included CL nominees submitted to the U.S. Global Change Research Program (USGCRP). The CL and CLA discussed the Northern Great Plains, which was part of the larger Great Plains region for the Third National Climate Assessment (NCA3), with each of these nominees and, as part of that discussion, solicited suggestions for other nominees. This long list of potential contributing authors was pared down by omitting individuals who could not contribute in a timely fashion, and the list was finalized after reconciliation against key themes within the region identified by past NCA authors, the CL and CLA, and contributing author nominees. The team of contributing authors was selected to represent the region geographically and thematically, but participants from some states who had agreed to contribute were eventually unable to do so. Others were unable to contribute from the start. The author team is mostly composed of authors who did not contribute to NCA3.

The CL and CLA, in consultation with past NCA authors and contributing author nominees, identified an initial list of focal areas of regional importance. The author team then solicited input from colleagues and regional experts (identified based on their deep ties to scientific and practitioner communities across the region) on their thoughts on focal areas. This list informed the agenda of a region-wide meeting held on February 22, 2017, with core locations in Fort Collins, Colorado, and Rapid City, South Dakota. The main purpose of this meeting was to seek feedback on the proposed list of focal areas. With this feedback, the author team was able to refine our focal areas to the five themes comprising the Key Messages of the Northern Great Plains regional chapter. Of these, recreation/tourism is a focus area that is new from NCA3.

Description of evidence base:

Multiple lines of research have shown that as a result of its high aridity, changes in water availability in the Northern Great Plains region are highly sensitive to small changes in climate.8c567c0c-cc42-4372-94ea-7abf677704c6,42117239-ceec-4a37-82cc-7041e25c8ce9,07ca2afc-e25e-4bae-9e72-16a5653acbe2,c09b2df8-4bd3-4a38-8879-308510262e8d Despite large differences in climate from the western mountains to the eastern plains, the reliance upon reservoir storage to regulate water supplies is ubiquitous—to provide water during times of drought and to mitigate flood waters during deluges.

Natural reservoirs, groundwater, and snowpack are at risk to varying degrees. Reservoir vulnerability was recently analyzed to assess sustainable pumping rates,bbb70780-07ef-4083-a3ff-8dc8d33b1e62 while snow and especially glaciers appear to be in steady decline in recent decades,bb0be3c7-6d67-4281-9ff4-db244460b65a attributed to global climate warming760d96a6-ba98-4e20-8897-2989d8f0ae6f that is projected to continue.29dec54f-92a8-4543-93f1-941da4f4d750

New information and remaining uncertainties:

While there is high confidence in future increases in temperature, uncertainties exist as to the changes in precipitation and runoff. Perhaps most important are the uncertainties in the degree of precipitation variability from year to year and within season (based on information dating to the 1950s).8c567c0c-cc42-4372-94ea-7abf677704c6,862fb345-9e70-4257-8e70-d714547099a9 These uncertainties are very likely to overwhelm the projected modest increases in precipitation.

Uncertainties exist in agricultural demands for water, reservoir operation protocols, and changes in extreme events.

Assessment of confidence based on evidence:

There is high confidence that temperatures will rise in the region, which will likely produce less snowfall and smaller mountain snowpacks. There is very high confidence in the downstream consequences of these changes.

This finding was derived from scenario rcp_4_5
This finding was derived from scenario rcp_8_5

You are viewing /report/nca4/chapter/northern-great-plains/finding/key-message-22-1 in HTML

Alternatives : JSON YAML Turtle N-Triples JSON Triples RDF+XML RDF+JSON Graphviz SVG