Climate variability, trends, and impacts on the Yukon-Kuskokwim Delta with insights into relationship-building to enhance climate science

Abstract

Climate change impacts in the Arctic and Alaska vary widely, providing opportunities to study regional complexities. This thesis, guided by insights from Yup'ik Elders from the Yukon-Kuskokwim Delta, explores the significant impacts of climate change and examines four key topics: climate-vegetation connections, shifting hydroclimate regimes, the role of large-scale climate patterns in tundra wildfires, and fostering community relationships. The first paper investigates tundra vegetation productivity trends which have decreased in the Yukon-Kuskokwim Delta despite increasing temperatures during the growing season, contrasting with other Arctic tundra regions. Using available long-term climate datasets, a coherent multi-decadal pattern involving spring sea-ice concentration in the East Bering Sea, growing season temperatures, and tundra productivity is revealed. This finding highlights that low-frequency variability can obscure long-term climate relationships. The second paper examines moisture dynamics in the Yukon-Kuskokwim Delta, revealing significant variability in moisture-related climatic factors. A comprehensive analysis of atmospheric data indicates a shifting hydroclimate regime in the Yukon-Kuskokwim Delta, with decreasing large-scale precipitation, increasing convective precipitation and evaporation, and fewer synoptic storms. The study underscores that warmer conditions and changing precipitation patterns can alter vegetation and overall landscape vulnerability to climatic changes. The third paper delves into early-season climate drivers of tundra wildland fires in the Yukon-Kuskokwim Delta. It establishes a baseline climatology for early fire seasons, connecting warmer temperatures and earlier snow-off dates with increased fire activity. It identifies May and June temperatures exceeding 15°C and snow-off dates before May 8 as key indicators for large fire seasons, emphasizing that lightning stroke counts crucially influence the area burned. Contrary to previous research, this study finds that May and June precipitation and spring sea-ice concentration are not primary drivers of tundra fires in the region. The findings suggest a future increase in fire frequency due to projected climate conditions. The fourth topic synthesizes perspectives on regional climate research, relationshipbuilding, and community engagement in Alaska. It discusses the importance of focusing on smaller regions for climate studies to build relevant, credible, and legitimate scientific endeavors with local communities. It emphasizes the value of cultural humility, self-reflection, and active community participation for effective climate science communication and relationship-building. This piece also addresses the systemic challenges of community work within academia and highlights the significance of volunteerism to enhance community-based climate research. Collectively, these papers underscore the intricate relationships between climate variables, tundra landscapes, and wildfire dynamics in Alaskan tundra regions, and the need for region-specific research approaches. The research concludes that community collaboration and culturally sensitive approaches are essential for impactful climate science.