The United Nations Intergovernmental Panel on Climate Change on Aug. 9 released a report on the impacts of climate change and how human activity is contributing to “unprecedented” and rapid change to the Earth’s climate. El Paso Matters wrote about what the report means for the Paso del Norte region.
To supplement that article, we’re offering an interview with Alex Mayer, a professor of civil engineering at University of Texas at El Paso. Mayer also directs UTEP’s Center for Environmental Resource Management. The interview has been edited for length and style.
El Paso Matters: Can you tell me a little about your day-to-day research?
Mayer: Broadly, I’m interested in water resources management, including the impacts of climate change on water availability and water scarce scenarios.
El Paso Matters: How does the newest report from the IPCC influence your work?
Mayer: We’ve known about climate change for several decades now. What stands out to me about this latest report is that the scientists are saying, unequivocally, that the incremental warming associated with climate change is due to human impacts, particularly the burning of fossil fuels.
This report is also, I think, more unequivocal about how catastrophic events like droughts and fires are associated with greenhouse gases. I hope that will cause people and governments to take it more seriously, and will push harder on policies to encourage using less fossil fuels.
I try to be optimistic. I was telling my son Monday morning as we were discussing the IPCC report that if I didn’t feel like people (could) still change, I’d have to quit my job. I try to remain optimistic that governments and people are willing to do things that will reduce their use of fossil fuels. I’m hoping this report will encourage that more.
El Paso Matters: Can you speak to the regional impact?
Mayer: The Rio Grande water supply that the city of El Paso relies on for irrigation and personal use originates in the southern Colorado, northern New Mexico area. That’s where climate change affects the headwaters, which affects water availability in the Rio Grande/River Bravo. We’re pretty certain that the snowpack that feeds the headwaters is going to decrease, and there’ll be an earlier melt-off of the snow.
Both of those things will contribute to more droughts because when water is there as rain or melting snow, it’s more vulnerable to evaporation. That means there will be less coming into our local water supply reservoir, at Elephant Butte (in New Mexico).
In climate science, we have these global circulation models that are used to make predictions on climate change and the predictions from those models can vary widely. But it’s becoming more and more apparent that all but the most optimistic models that we’re using are showing that on average, the water supply in the Rio Grande is going to be reduced by at least 10%. And the more dire models predict at least 20%.
Those predictions also say that not only will droughts will be more frequent, but more likely to be multi-year occurrences. We’ve seen in the last decade or so that the Rio Grande water supply is becoming less and less reliable, and that’s certainly going to be the case in the future. And what that does is it places greater reliance here on groundwater.
In past drought years, including this year, we see when we have less Rio Grande water, farmers still need to irrigate their crops. They use more groundwater, and cities like El Paso will also use more groundwater. We have a couple of aquifers that El Paso water depends on in addition to Rio Grande water. Everybody knows that we’ve been pumping those aquifers at a rate much greater than the recharge to those aquifers for many decades. We’re concerned that, for example, the Hueco Bolson aquifer (underneath El Paso), the freshwater part of that will be depleted in a matter of a few decades.
El Paso Matters: How have your thoughts or conversations on climate change evolved over the last two decades?
Mayer: I used to live in the Upper Peninsula of Michigan. We’ve lived in El Paso since the beginning of 2020 but I’ve worked on projects in the region for the last five or six years. What I think about more and more is, how can we make our desert cities livable? What are we going to need to do to adapt to climate change in our desert cities in the United States and along the border? And I don’t have any answers.
We need people to be more aware that water is a very fragile thing. It’s already impacted by climate change and will become even more so. Our water utilities probably will always be capable of finding more water. But that might mean building pipelines further and further away from our cities. Both Ciudad Juárez and El Paso Water are looking at importing water in the future, because they’re aware that the groundwater supplies aren’t going to last forever. Hopefully, they have some awareness that the Rio Grande is also becoming less than less reliable.
As you look farther and farther away for more water, or as you use more and more desalination or wastewater reuse, the cost is going to go up. One concern my colleagues have is, are we going to get to the point where the water bill, especially for lower income people, is going to become a significant part of their budget?
Are we going to see people that are going to be spending 10% of their income, 15% of their income, maybe more than 20% of their income on their water bills? OK, if water bills will go up, maybe that will encourage people to use less. We’re not going to run out of water, people will have enough water, certainly to drink, but I’m worried that we might see sort of equity problems.
The other thing to worry about locally is increasing temperatures. When I talk to my friends in the Upper Peninsula of Michigan, they say, ‘Oh, it’s already hot there. So what’s the big deal?’
It depends on which of these models you believe, but I think we’re looking at increases in daily temperatures by at least a few degrees Fahrenheit. The most pessimistic models double that. You think about average temperatures that may change slowly over the next 70 years or so. Incrementally you have higher average temperatures — which also means having more extremely hot days, over 100 degrees or even over 104 degrees. At that point, we’re starting to be concerned about the health impacts on people.
In a relatively low-income place like El Paso, not everybody can afford refrigerated air conditioning, and are depending on evaporative coolers or swamp coolers.
I’m a little worried that again, it’s going to be sort of a “have and have-not.” Some people will be able to afford to keep cool during those extreme hot days, but other people will not.
Cover photo: Water pours into an irrigation canal near Garfield, N.M., in June. Climate change is expected to greatly lessen the amount of water in the Rio Grande. (Corrie Boudreaux/El Paso Matters)