Overpeck: Reducing GHGs, Adaptation Needed for 'Storm'
A "perfect storm" of population growth, drought, and climate change threatens residents of the Colorado Basin, according to Jonathan Overpeck, co-director of the Institute for Environment and Society at the University of Arizona.
Speaking to the U.S. House of Representatives Subcommittee on Water and Power last month, Overpeck said two broad solutions working in tandem are required to deal with it:
- mitigating climate change through reducing greenhouse gas emissions,
- developing the capacity to adapt to climate variability and climate change in the future, especially drought.
Special attention should go toward developing renewable energy resources like solar and wind, he added.
While climate scientists currently are unable to predict the occurrence of such droughts with any confidence, Overpeck said, that what they do know is that the Lower Colorado Basin is regularly hit by multiyear, and even multidecade drought, and in all likelihood the region will experience such devastatingly severe droughts in the future. The longest droughts in North America, such as those during the medieval era, coincided with periods of above-average temperatures.
Evidence from climate models also points to human activity as the source of changes in vegetation patterns and wildfire frequency. Overpeck said the bottom line is that the Lower Colorado River and neighboring regions could become the most ecologically threatened systems in the United States. The paradox is that even though there would be less water, rainfall, when it happens, could be more intense and could cause more flooding.
The twofold solution, Overpeck told the committee, requires a significant reduction in carbon dioxide and other greenhouse gas emissions. "Reductions by 2050 to levels 80 percent below 1990 levels is a good target," he said, adding that the Southwest has "the greatest power potential in the nation and has significant wind assets that can be tapped to curb emissions."
The second step is a 10-year, $200 million "federal stakeholder-driven science and services program" to create the knowledge and the access to that knowledge that decision makers could use to plan for future adaptations.
The program would be similar to the current Regional Integrated Sciences and Assessments model funded by the National Oceanic and Atmospheric Administration. That model incorporates research from university-based laboratories as well as federal laboratories.
"Not only would such a science and services program help avert future water conflict among states, Native nations and Mexico, it would also provide the capacity to deal with other implications of continued population increases, drought and climate change: threats to the region's ecosystems, public health, agriculture, ranching, air and water quality and much more," he said.