DL: How has your research been involved in providing evidence of global climate change?

DG: “I was a lead author on the IPCC (Intergovernmental Panel on Climate Change) report that came out in late 2013 — that is assembled by the United Nations every six or seven years — to assess climate change research. That report confirmed previous assessments that there was incontrovertible evidence that the planet is warming up; that there was increased confidence that the increase was at least partially due to human activities, mainly increased greenhouse gas concentrations; and that the increase in greenhouse gas concentrations and the increase in surface temperature is highly likely to continue this century.



“The report that I worked on was Volume One in a three-part assessment. It was then followed by two other volumes that had to do with the impacts of what we see happening in the climate system, and possible approaches to doing something about it — so-called mitigation of climate change. The third part was designed to assess the possibility of doing something about increased emissions using various techniques, and what the possible implications of those different approaches would be. But it’s up to policy makers to use that information.”

DL: How important is politics to the issues of getting people to understand climate change, and getting the powers that be to do something about it?

DG: “Like any politicized issue, the answers you get from members of the public or policymakers depends crucially on precisely what question you’re asking and how it’s asked. The whole issue of climate change is eminently spin-able politically. So as scientists we need to be extremely careful to say that while there is incontrovertible evidence that the climate is getting warmer, that does not by itself indicate any particular cause. My own opinion, and the opinion of most mainstream climate scientists, is that what we’ve seen over the 20th century is a combination of a response to greenhouse gases; plus a response to other climate forcings, some of which may be caused by people and some which may be natural; plus just some natural variability. People who say that ‘it’ is a hoax — that type of response is just silly and not worth taking seriously. But there is very serious debate about just how much of warming is due to increased greenhouse gases.”

DL: What about people — policy makers and scientists — who say that regardless of whether or not it’s man-made, it’s too late to do anything about it and now we just need to figure out how to deal with the damage?

DG: “What they’re saying is that we need to adapt to climate change rather than mitigate it. Those are two possible responses to warming. What I would say is that we must adapt, for the simple reason that climate change is already happening and is almost certain to continue at some rate. So adaptation is not a choice at this point. But I personally don’t think that it’s wise to restrict ourselves to thinking only about adaptation. I think that would be a very selfish choice. My generation could get away with that, but my own personal opinion is that that approach is unethical.”

DL: What would you like to see governments and businesses doing differently to address some of these issues?

DG: “The first thing is to have our best science taken seriously by policymakers. The fact that 2014 was modestly warmer isn’t hugely significant by itself, but it is a milestone of sorts. And if that climate milestone helps us get beyond the sillier aspects of the debate about global warming, like whether or not it’s real, then that’s a good thing. And I think that ship is slowly turning, and the view that there’s some international hoax going on is ridiculous and we need to get past it.

“My own opinion of the approaches to mitigation are that if, as a society, we took this problem seriously, decided to do something about it, and turned it into an engineering problem rather than a political problem, we could make a lot of progress.”

DL: With the legislative session in Santa Fe beginning, how do you think New Mexico is doing in addressing these problems?

DG: “At the end of the Richardson administration a cap-and-trade scheme for emissions was proposed and actually passed, and that was one of the things that candidate (Susana) Martinez campaigned against when she first ran for governor. And when she won, early in her administration, that was repealed. I’m unaware of any statewide mandated efforts to deal with greenhouse gas emissions since then. I’d be surprised if that was high on the agenda for the state this year. I think people are more concerned about the price of oil and gas and not the emissions they create.”

DL: If things continue going as they are, what kinds of issues will we start dealing with here in New Mexico in the next 20 years?

DG: “Among the things we’re studying in my research group is the ongoing decrease in snow pack that is certainly predicted to occur as the climate warms up. We’re seeing evidence of that in the data, and that has consequences for stream flow in a significant way. As snow pack at high elevations decreases, we have shorter snow seasons, the snow melts earlier, and evaporation rates go up. That’s what we’ve been seeing for the past several decades. Projections are that stream flows will ultimately decrease due to higher temperatures, almost regardless of what happens to precipitation.

“There are some important consequences of this especially for water resources. If projections of increased warming continue, then that effect will get larger and larger. The most direct effect here locally will be a decrease in water resources. In an arid region like this where we’ve spent much of the 20th century depleting groundwater resources, then the prospect of smaller amounts of surface water — I don’t think anyone would characterize that as good.”

DL: What can concerned students and citizens do to help reduce the problem?

DG: “There are many things we can do locally as wise stewards of both energy and water. The two really go together. I think our society has made some strides locally in conserving water and energy, and those efforts need to be supported and continued. At some point we really will have no choice but to deal with fossil fuels, which is difficult for New Mexico because the state budget depends on revenue from them. But I think that’s something unavoidable in our future.”

Jonathan Baca is the news editor for the Daily Lobo. He can be reached at news@dailylobo.com or on Twitter @JonGabrielB.