Why AZ isn’t on greenhouse gas list
Lord Kelvin, the 19th-century British physicist who created the Kelvin temperature scale, is often quoted as having said something like “When you can measure what you are speaking about, and express it in numbers, you know something about it. When you cannot express it in numbers, your knowledge is of a meager and unsatisfactory kind.”
The specifics of the wording and attributions are debated, but the sentiment — that measuring a problem helps to understand and address it — is one shared by many scientists before and since.
Earlier this month, the U.S. Environmental Protection Agency released its first publication of state-specific greenhouse gas data. It adds resolution to the nationwide Greenhouse Gas Inventory the EPA has produced every year since 1997 in an effort to meet U.S. commitments to the United Nations Framework Convention on Climate Change (UNFCCC).
According to the EPA’s March 8 news release, the resource includes tools intended to help states compile their own emission estimates, as well as “information on state-level opportunities to reduce emissions of highly-potent greenhouse gases.”
The federal effort also recognizes official state inventory reports produced by individual states that, in many cases, outline a custom-designed plan for monitoring and addressing their own emissions. Nevada has one, published by its Division of Environmental Protection. New Mexico offers a forecast from its state-sponsored Climate Change Task Force. Alaska and Louisiana have also participated.
Arizona is not on that list, along with about half of U.S. states.
To measure or not to measure
The omission is not because it’s impossible to measure or calculate greenhouse gas emissions for Arizona. In fact, the EPA produced a fact sheet summarizing Arizona’s greenhouse gas emissions for 2020.
It may have more to do with state politics dating back to a 2010 law that prevents state agencies from even monitoring greenhouse gas emissions, as reported by The Arizona Republic in 2020. Although cities in Arizona have made progress on developing individual climate action plans in recent years, the state still lacks an official, coordinated statewide effort similar to those published by the EPA for 24 other states, plus the District of Columbia and Puerto Rico.
But restricting the local collection of emissions data does not make it impossible to get. It may just render our knowledge more meager and unsatisfactory, as Kelvin might have said.
Based on information from required reports submitted by large emitters, fuel and industrial gas suppliers and CO2 injection sites, the EPA estimates that 95 facilities in Arizona released nearly 43.7 million metric tons of carbon dioxide in 2020, with 85% of that coming from power plants. That’s 16 million metric tons of CO2 more than what was emitted by 94 large facilities in New Mexico and more than twice as much as was released by the 41 large facilities in Nevada.
This number does not include emissions from petroleum and natural gas production systems that cross state boundaries or electric distribution systems data that is reported at the corporate level. But there are ways to get at this information, too.
Kevin Gurney is a professor of Informatics, Computing and Cyber Systems at Northern Arizona University in Flagstaff. He has dedicated decades to figuring out how to calculate carbon emissions globally based on images from space that show building design, and activity data that gives insight into things like fuel usage. In February 2021, he published a study in the journal Nature Climate Change that concluded that many U.S. cities under-report their own emissions. He doesn’t blame the cities. And he says he can fill the gap.
“Interestingly, we always have more data than the cities do,” Gurney said. “One of our conclusions from that 48cities study is that they were missing a lot of data. It’s not that they didn’t have access to it. It’s that they don’t have the advantage of having spent 20 years on this, scraping data elements.”
Science and math, Gurney says, can fill in data gaps created by state politics. And the consistent and tested methodology used by experienced but distant researchers can be more accurate than reports produced by local agencies newer to the game. But some environmentalists think it shouldn’t come down to that.
“This governor has been reluctant to say the words ‘climate change.’ We really don’t have statewide plans relative to climate and climate resiliency,” said Sandy Bahr, director of the Grand Canyon Chapter of the Sierra Club, in an earlier interview. “Cities are doing it but we really do need a state plan. Instead, what we have is a provision in our statutes that prohibits the department of environmental quality from doing anything to limit greenhouse gas emissions unless the legislature specifically authorizes it, which they’re not doing.”
Climate science transcends politics
Gurney can run his climate models without the help of state governments, and has consulted with the White House recently on the need for a consistent, coordinated effort that transcends state compilations. But he agrees that Arizona should participate in monitoring its own greenhouse gas emissions.
“I want my state to be out front and be a player in this very important topic,” he said. “We have an important role to play, and I would hate for my state to miss that opportunity.”
Scientists can produce results that show where the largest sources of emissions are coming from in each state, county, city or neighborhood. Some of that information is already readily available in public databases. Springerville Generating Station, located northeast of Phoenix near the New Mexico border, for example, was the leading emitter of CO2 in Arizona’s facility and industry sector in 2020.
But data, though just as valuable as Lord Kelvin and others have always
maybe said, doesn’t translate into state climate action by itself.
In this month’s news release, EPA administrator Michael Regan wrote that “tackling the climate crisis requires action across all levels of government, and our partnership with states has never been more important to reduce emissions and deliver solutions.”
Gurney says he’s seen more activity in the last year on climate issues nationally than he has in the previous 15. He just wants his own state to get on board.
“Unfortunately climate change has now become tribal, where you’re on the left or you’re on the right,” Gurney said. “But for those of us in science, it’s sad. It’s just a tragedy.”
Joan Meiners is the Climate News and Storytelling Reporter at The Arizona Republic and azcentral. Before becoming a journalist, she completed a Ph.D. in Ecology. Follow Joan on Twitter at @beecycles or email her at joan.meiners@arizonarepublic.com.