Climate change could lead to worsening water scarcity in New Mexico and state officials hope they can plan for hotter and dryer decades.
Earlier this month, state officials led by the New Mexico Bureau of Geology and Mineral Resources and Interstate Stream Commission published a draft analysis as part of its 50-year water plan, aiming to identify impacts on water supplies in the state and strategies to conserve and maintain resources.
Along with the release of the draft Sept. 16, the State opened a public comment period to solicit feedback from the public on the report with Oct. 15 the deadline for submitted comments.
The report compiled existing research on the future impacts of New Mexico’s changing climate on its water resources, intended to provide a basis for future water planning by agencies across the state.
It was in response to a directive from Gov. Michelle Lujan Grisham that the State find ways to ensure its water resources are sustainable for the next half-century.
“The guiding principle is that the state charts a course that will allow for more flexibility in managing water supplies and infrastructure in the face of weather extremes brought on by a changing climate,” read the Bureau’s announcement of the draft plan’s publication.
“The Governor has long recognized the importance of water to the arid state. As outlined by the Governor, the pillars of the 50-Year Water Plan are stewardship, equity, and sustainability.”
Here are the key takeaways from the State’s 50-year water report.
The future: hotter and dryer
New Mexico showed a “clear and pronounced” warming trend, the report read, resulting in decades of drought.
While the report admitted to some gaps and unpredictability in rainfall, it reported with “certainty” that temperatures would heat up.
The report predicted the spring would become increasingly dry, potentially pushing back the summer monsoon which the state relies on for much of its moisture.
Less moisture could also mean smaller snow packs in the mountains of northern New Mexico, which melt and feed rivers throughout the state, along with dryer soil and vegetation leading to move wildfires.
“Evidence derived from model projections suggests a high likelihood of continuing temperature increases coupled with pronounced precipitation variability,” the report read. “Episodic droughts, when they occur, will become much more severe as temperatures increase.”
To mitigate the increasing aridity expected in New Mexico, the report said government policy changes were needed to mitigate greenhouse gas emissions known to impact climate change.
“New Mexico is projected to become hotter and more arid over the next 50 years, as the result of human-caused climate change,” the report read.
“A strong, long-standing scientific consensus from these reports indicates that New Mexico should plan for a hotter, more arid climate, with a rate of change dependent on global policy to mitigate greenhouse gas emissions.”
Climate change to impact New Mexico’s ‘water budget’
Water for human consumption in New Mexico comes exclusively from rainfall and snow packs, the report read, meaning more arid conditions could reduce availability for people for needed purposes such as recreational and industrial uses.
About 95 million acre feet per year comes precipitation like rain, the report read, while about 96 percent or about 92 million acre feet is lost to evaporation or is released by vegetation through a process known as transpiration.
This means only about 3.4 percent, about 3.2 million acre feet is left on the surface as runoff or to recharge aquifers and rivers.
Surface water supplies will become increasingly sensitive to changes in the climate as a result of the small portion of its available water left over.
“Small changes in the land-surface water budget can thus have a major impact on human society,” the report read.
Continued changes in New Mexico’s climate could impact vegetation
More frequent die-offs of forest and intensifying wildfires were brought on recently by changes in New Mexico’s climate as it shifts to hotter and dryer conditions, the report read.
Changes in vegetation can impact ecosystems and hydrology throughout the state, read the report, leading to changes in available water for people in every region of New Mexico.
Available water, temperature and sunlight were the main driving factors defined in the report that impact vegetation productivity.
“Ongoing regional climate change toward warmer temperatures and more severe droughts therefore threatens vegetation types that are sensitive to hotter, drier conditions,” the report read.
Adrian Hedden can be reached at 575-618-7631, [email protected] or @AdrianHedden on Twitter.