Summary/Abstract
This expert report was written by Peter A. Erickson and filed by plaintiffs in the case Held v. State of Montana.
In this report, the author assesses emissions attributable to three categories of activities in Montana: “extraction of fossil fuels; processing and transportation of fossil fuels; and consumption of fossil fuels by end users.” For each category, the author quantifies “the amount of coal, oil, and gas, both in units of energy and in units of carbon dioxide (CO2) emissions released from the fuels once combusted.” The author finds that, in 2019:
- “Total annual fossil fuels extracted in Montana led to about 70 million tons of CO2 being released into the atmosphere once those fuels were combusted. Montana’s fossil fuel extraction was dominated by coal, for which extraction levels were far higher than in major economies such as Brazil, Japan, Mexico, Spain, or the United Kingdom.”
- “Total annual fossil fuels consumed in Montana led to about 32 million tons of CO2 being released into the atmosphere. Montana’s fossil fuel consumption has also been dominated by coal, but that is starting to change, as oil (in the form of gasoline and diesel) and gas have been increasing, while coal has been decreasing. Montana’s annual CO2 emissions from its fossil fuel consumption are on par with those from several countries around the world, including Ecuador, Ireland, New Zealand, Norway, Sweden, or Switzerland.”
- “Montana is also a fossil fuel thoroughfare, such that annual fossil fuels transported through or refined in Montana led to at least 80 million tons of CO2 being released into the atmosphere, once those fuels were combusted. Oil comprised the largest share of fossil fuels transported through or refined in Montana, as major oil pipelines traverse the state, and four oil refineries operate in the state.
- “Accounting for overlap between the categories above (e.g., coal that is both extracted and combusted in-state), the total CO2 emissions associated with Montana’s fossil fuel-based economy are on the order of 166 million tons CO2 being released into the atmosphere annually. This is a substantial quantity of emissions, contributing to increasingly severe risks of climate change, and which is equivalent to the recent annual CO2 emissions associated with the countries of Argentina, the Netherlands, or Pakistan.”
In a subsequent rebuttal expert report, filed by plaintiffs on November 28, 2022, the author responds to the expert reports of Dr. Terry Anderson and Dr. Judith Curry, filed on behalf of the State of Montana, and reiterate the conclusion of their September 30, 2022 expert report.
The underlying case, Held v. State of Montana, arose when, on March 13, 2020, sixteen young people filed a lawsuit in a state court in Montana, United States, asserting climate change-based claims under the Montana constitution against the State of Montana, its governor, and state agencies. In particular, the case challenged the constitutionality of Montana’s fossil fuel-based State Energy Policy and the “Climate Change Exception” in the Montana Environmental Policy Act. For more information about this case, visit the Sabin Center’s Climate Litigation Database.
Note: This climate attribution research was presented in the context of a contested legal proceeding. Different countries, courts, and legal forums may have different standards for expert testimony, and may conduct fact-finding based on legal standards of proof that differ from those applied in academic publishing. Readers should independently investigate and understand the bases for the assertions made in this document before applying this research in other contexts.