With California facing unprecedented water restrictions this summer, area residents may be breathing a sigh of relief that Navajo County is located atop one of the largest groundwater aquifers in the nation. A long-term prediction by National Aeronautics and Space Administration (NASA) researchers, however, points to Northern Arizona and New Mexico as the worst-hit areas in the West in terms of soil moisture in an epic “mega-drought” predicted over the course of the next 30 years.
“Our results point to a remarkably drier future that falls far outside the contemporary experience of natural and human systems in Western North America, conditions that may present a substantial challenge to adaptation,” the report states. “Human populations in this region, and their associated water resources demands, have been increasing rapidly in recent decades, and these trends are expected to continue for years to come. Future droughts will occur in a significantly warmer world with higher temperatures than recent historical events, conditions that are likely to be a major added stress on both natural ecosystems and agriculture.”
The report, which was published in February by the American Association for the Advancement of Science (AAAS), offers the most dire predictions of any drought studies and reaches a different conclusion than the Intergovernmental Panel on Climate Change assessment report, which found that future drought conditions are uncertain.
Unlike many of the other studies conducted on drought conditions in the West, the NASA team included historical and paleoclimate records, as well as potential “global-warming induced” climate changes and continuously increasing water demands by a growing population. The resulting picture is an extremely dry landscape with depleted groundwater resources throughout the Southwest, and incredibly low soil moisture levels in Northern Arizona by 2050.
According to the study, the driest period for the region occurred during a Medieval-era mega-drought. Information gleaned from tree rings was used to determine drought conditions from eras pre-dating historical records. The study concludes that the mega-drought expected to occur in the Southwest for a period of at least 30 years will be even drier than the one experienced during the 11th century.
“Ultimately, the consistency of our results suggests an exceptionally high risk of a multidecadal megadrought occurring over the Central Plains and Southwest regions during the late 21st century, a level of aridity exceeding even the persistent megadroughts that characterized the Medieval era,” the report notes.
In short, the report states that if the predictions are accurate, the lifestyle of future generations in the region will be significantly altered given the lack of moisture and depletion of groundwater.
“Perhaps most importantly for adaptation, recent years have witnessed the widespread depletion of nonrenewable groundwater reservoirs, resources that have allowed people to mitigate the impacts of naturally occurring droughts,” the report states. “In some cases, these losses have even exceeded the capacity of Lake Mead and Lake Powell, the two major surface reservoirs in the region. Combined with the likelihood of a much drier future and increased demand, the loss of groundwater and higher temperatures will likely exacerbate the impacts of future droughts, presenting a major adaptation challenge for managing ecological and anthropogenic water needs in the region.”
