Abstract
In a world of uncertainty and change, leaders should base their decisions on best available scientific evidence. However, history has shown that science is often inadequately incorporated into the decision-making process. This dissertation investigates three environmental issues to identify the challenges of considering Earth system dynamics in policymaking and management. I also propose solutions for improving the two-way exchange of knowledge and values between researchers and policymakers. In chapter one, I investigate subsea permafrost carbon sensitivity to climate change using an expert assessment. The analysis revealed that subsea permafrost contains significant carbon stocks and is already contributing to climate change through the release of CO2 and CH4. However, the lack of field data and high uncertainty regarding carbon stocks and emissions make it challenging to accurately predict the impact of subsea permafrost on future climate. Despite these challenges, experts agreed that ignoring this system in climate change policies increases the risk of underestimating ecosystem feedbacks and overshooting climate targets. In chapter two, I conduct a comprehensive global study on the changing wildfire regimes from the Holocene (11,700 years BP) to projections for the year 2300, utilizing expert assessment to analyze the complex interactions among climate, vegetation shifts, and human activity. Experts believe that the rate of fire regime alteration has increased ten-fold in the last 250 years, primarily due to land use and anthropogenic climate change. The study predicts intensified fire regimes with increased fire activity and reduced ecosystem services in most biomes under higher emissions. We offer management recommendations to preserve ecosystem services. However, the experts describe how predicting the interaction between fire regime drivers remains a significant knowledge gap and vulnerability. In the final chapter, I focus on the intentions and performance of water megaprojects as solutions to water-related problems. I investigate a range of water megaprojects as case studies tracing the origins, justifications, and impacts of megaprojects from around the globe. Despite abundant evidence that these projects usually do not achieve their stated purpose, unstated ideological and economic justifications lead to continued support for water megaprojects. These justifications include prioritizing short-term goals over long-term sustainable development objectives, the significant influence of powerful interest groups, inadequate understanding of the natural water system, favoring personal values over scientific evidence, and biased risk analysis resulting in low success rates. While my dissertation highlights significant challenges in science policy integration, it suggests that substantial progress is possible through sensible changes in incentives and operations, reducing policy risks, and enhancing the relevance of natural sciences research.
Degree
PhD
College and Department
Life Sciences; Plant and Wildlife Sciences
Rights
https://lib.byu.edu/about/copyright/
BYU ScholarsArchive Citation
Sayedi, Sayedeh Sara, "Combining Expert Opinions to Assess Risk of Change in Earth Systems: Permafrost Collapse, Global Wildfire, and Water Security" (2023). Theses and Dissertations. 10572.
https://scholarsarchive.byu.edu/etd/10572
Date Submitted
2023-09-14
Document Type
Dissertation
Handle
http://hdl.lib.byu.edu/1877/etd13409
Keywords
expert assessment, climate change, subsea permafrost, fire regimes, water security, decision making
Language
english