Climate change, the Rio Grande forecast problem, and the death of stationarity

Laura Paskus takes us this morning to the mountains of northern New Mexico, where the snow is melting earlier than it used to, and less of the ensuing runoff is making it into our Rio Grande:

[A]s bleak as southwestern springtime stream flow forecasts have been in recent years, scientists at the University of New Mexico are now saying that actually, they’re probably not bleak enough.

“The warm spring temperatures are one of the clearest observed climate change signals in North America,” says David Gutzler, a professor in the University of New Mexico Earth and Planetary Studies Department.

Gutzler is part of the New Mexico Universities Working Group on Water Supply Vulnerabilities, which has been working on identifying points of vulnerability in our societal-ecosystem-water system. One of their key findings, developed by Gutzler’s student Shaleene Chavarria, is that changes in the climate weaken the old forecast tools, which are used to relate winter snowpack to runoff the following year.

This is the point Chris Milly, Julio Betancourt, and colleagues laid out in an important paper a few years back on “the death of stationarity” (pdf). “Stationarity” was a foundational assumption in water management – that the range of observed variability in the past provides a usable picture of the expected range of variability and system behavior in the future:

In view of the magnitude and ubiquity of the hydroclimatic change apparently now under way, however, we assert that stationarity is dead and should no longer serve as a central, default assumption in water-resource risk assessment and planning. Finding a suitable successor is crucial for human adaptation to changing climate.

The Paskus piece is part of a new reporting project being done by New Mexico In Depth, a non-profit news organization based here in New Mexico.

Biker wedding, Albuquerque New Mexico

Bandidos wedding, Pat Hurley Park, Albuquerque

Bandidos wedding, Pat Hurley Park, Albuquerque

Lissa and I were sitting this afternoon in Pat Hurley Park, up on the west mesa (best view in Albuquerque, check it out) when we heard the rumble of Harleys. A couple of dozen bikes, a full biker wedding. And, being an outlaw gang – Bandidos, whose regalia included New Mexico “bottom rockers” (see Jeff Proctor’s famous bottom rocker story for an explanation) – they of course rode right up onto the lawn for the photo shoot.

You can see it was a nice spot for their wedding pictures on a perfect fall afternoon.

I love Albuquerque.

Cadiz, scientization, and how Dan Sarewitz almost drove me out of journalism

Ian James at the Desert Sun this week took on the journalistic task of rounding up the back-and-forth over the politics, law, policy, and science of the Cadiz project, a proposal to pump groundwater in the deserts of Southern California and ship it off for use in coastal plain cities.

Ian, who’s earned a reputation in recent years as one of the smartest reporters working on the science of climate and water in the arid southwest (the American Meteorological Society recently honored him for his work) does a solid job on the politics, law, and policy, and then does the best any of us can hope to do on the science in a situation like this, which is punt.

The science questions here are two, which overlap: would the project harm sensitive desert ecosystems and environments, and would it really yield the amount of water its proponents claim. The project’s supporters say their science clearly supports “no” to the first and “yes” to the second. The project’s opponents say the opposite.

Three years ago, I made a prediction: science won’t settle Cadiz. We have more science. The question isn’t settled.


In 2004, political scientist Dan Sarewitz wrote a paper that changed the trajectory of my journalistic career: How science makes environmental controversies worse. I had long imagined that my job as a science journalist was to understand what science had to tell us about important political and public policy questions and then explain it in a way that would help influence positive outcomes. By that time in my career (a couple of decades in) I had spent a lot of time at the effort, and it didn’t seem to be going well. Sarewitz’s paper offered an explanation:

[S]cientific uncertainty, which so often occupies a central place in environmental controversies, can be understood not as a lack of scientific understanding but as the lack of coherence among competing scientific understandings, amplified by the various political, cultural, and institutional contexts within which science is carried out.

The more I learn about groundwater hydrology, the more I realize it is an epistemological task steeped in genuine uncertainties. You can’t really look underground directly, data’s sparse, resulting answers you get are based really importantly on the modeling assumptions you make. And so it is not surprising under any circumstances to have different scientists come up with different answers. You sorta expect it.

Sarewitz isn’t making a postmodernist argument that permits any science to be true (ick that). Rather, it’s an up front recognition of the inherent limitations of the scientific enterprise:

[N]ature itself—the reality out there—is sufficiently rich and complex to support a science enterprise of enormous methodological, disciplinary, and institutional diversity. I will argue that science, in doing its job well, presents this richness, through a proliferation of facts assembled via a variety of disciplinary lenses, in ways that can legitimately support, and are causally indistinguishable from, a range of competing, value-based political positions. I then show that, from this perspective, scientific uncertainty, which so often occupies a central place in environmental controversies, can be understood not as a lack of scientific understanding but as the lack of coherence among competing scientific understandings.

Sarewitz maps what happens in the face of those limitations to the political and policy process. In “scientized” debates, political actors with differing value position attempt to win the argument about policy by winning the argument about science, picking from among competing scientific interpretations that which supports their value position. Importantly, Sarewitz is not arguing that the question of who pays for the science is influencing the results (though that’s an issue), but rather that this is an inherent problem.

It made the journalistic task seem hopeless to me for a time, but quitting wasn’t really an option. I had no other useful skills, though I did start joking about taking up welding. And there are, in fact, science-politicized debates (like the more egregious folks unwilling to deal with real climate science) where journalism can help. But Sarewitz also pushed me toward a bit more humility about how the nature of science related to the things I could accomplish with my journalism. And it forced me to look more closely at the value propositions underpinning debates over the genuine uncertainties in science-related political and public policy questions, helping me to sidestep some of the problems posed by scientization.

When I took to social media today to point to the connection between Sarewitz’s ideas and Ian’s Desert Sun story, the flack for Cadiz had this response:


Kinda made my point for me.

Turns out Casablanca isn’t a desert. I was misinformed.

One of my favorite water nerd film moments is the conversation between Humphrey Bogart and Claude Rains in which Rains’ Inspector Renault tries to get Bogart’s Rick to explain why he came to Casablanca:

the fog should have clued me

the fog should have clued me

Captain Renault: What in heaven’s name brought you to Casablanca?
Rick: My health. I came to Casablanca for the waters.
Captain Renault: The waters? What waters? We’re in the desert.
Rick: I was misinformed.

I love it even more now, after blog commenter Paul pointed out that Casablanca’s coastal climate is particularly wet in winter. It’s not a desert after all.

I was misinformed. (And I love my blog’s readers.)

The last time Lake Mead was full, as seen from outer space

My new hobby, hunting for pictures of Lake Mead when it was full, led me this evening to the helpful USGS EarthExplorer archives of old U.S. government satellite images, where I found this little beauty. Apologies if it’s a slow load, they’re relatively large image file so interested water nerds can click on it and zoom and stuff. You can see that Saddle Island, near the center of the picture, is actually an island. The old Las Vegas Bay marina is still there on the branch on the upper left of the image. May 2000 is the last time Mead’s surface elevation was above 1,200 feet above sea level, and as Southern California water manager Bill Hasencamp told the L.A. Times last week, we’ll probably not see it full again in our lifetimes.

Landsat image of Lake Mead, May 3, 2000

Landsat image of Lake Mead, May 3, 2000

For comparison, here’s Lake Mead taken Oct. 12 of this year. I tried to crop ’em sorta the same:

Landsat image of Lake Mead, May 3, 2000

Landsat image of Lake Mead, Oct. 12, 2015

A farmer’s defense of the Klamath Basin Restoration Agreement

The Klamath Basin Restoration Agreement embodies one of the great experiments in collaborative watershed management under contested conditions, with a complex web of sometimes conflicting interests among agriculture, indigenous communities, fisheries, environmental flows, and power production. It also demonstrates one of the great risks in collaborative water management in the arid West: everyone has to give up something, and there is always a risk that politicians pandering to any one faction can gain traction and sabotage the deal. The incentives of local politics pose huge risks.

Ben Duval, a farmer who clearly has some heartburn about the compromises required but supports the KBRA, makes that case eloquently in op ed this weekend:

The KBRA and the related Klamath Settlement Agreements are a product of simple reality — we don’t live in a bubble. Other viewpoints are part of the local, regional and national debate about water. We have to acknowledge the reality that the public sentiment places a high value on the environment, healthy fisheries and other ideals. There is no doubt they also appreciate the safe, stable, and affordable food supply that irrigated agriculture is so effective at providing. However, we cannot simply dismiss the other values that are important and also depend on our Klamath River.

Thanks to Michael Campana for the pointer.

Albuquerque’s water use down another 3.4 percent in 2015

I keep asking my friends who manage municipal water systems in the West how low their communities’ water use can go. None of them really know, which is fascinating. Their customers’ water use just keep dropping.

I’ve been following a couple of communities particularly closely – Albuquerque (because it’s my home town) and Las Vegas (the focus of a lot of my research attention for my book). The two communities also are a useful comparison because both do accounting in a sufficiently similar way that I’m able to do reasonable apples-to-apples comparisons. (Municipal comparisons are a notoriously difficult problem because of different accounting approaches, especially with respect to effluent return flows.)

In 2014, water use in Las Vegas dropped dropped another 3 percent, to 205 gallons per capita per day, part of a long, steady slide. It’s dropped 38 percent in the last decade. I don’t have good 2015 Las Vegas data yet, but based on the preliminary Bureau of Reclamation reports, it looks like consumption of Lake Mead water in Southern Nevada in the first nine months of this year is down another 1.5 percent from the same period last year.

Welcome to Albuquerque, Desert Sands, swimming pool for registered guests only, by John Fleck

Empty Albuquerque swimming pool, using less water. by John Fleck

I just got Albuquerque’s numbers for the first nine months of the year, which are down 3.4 percent from the same period last year. That should put us at somewhere between 130 and 131 gallons per capita per day this year, a 48 percent reduction in water use per person since 1995.

This kind of reduction in per person use of a critical resource is astounding, and says two important things, I think. The first is that we were pretty profligate with our water use until quite recently. The second is that it’s still not clear where the water conservation floor lies.

Note on data for the water nerds: These numbers are based on total withdrawals. My calculations for consumptive fraction: Albuquerque 55 gpcd, Las Vegas 120. See here for background on the difference.