Effect of climate change on Arctic water quality

Sarthak, Karki

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Author

Sarthak, Karki

Chair

Aggarwal, Srijan

Committee

Dev, Subhabrata
Toniolo, Horacio

Abstract

Climate change is fundamentally altering Arctic hydrological systems, impacting water quality and posing challenges for communities dependent on these vulnerable sources. This study examines water quality trends across three distinct Arctic contexts: (1) Arctic glaciers, (2) the Yukon River Basin (YRB), encompassing a five-year dataset (2019-2023) of dissolved organic carbon (DOC), sulfate, and stable water isotopes (δ2H, δ18O, and d-excess) across varying permafrost regions and seasons, and (3) Shishmaref, Alaska, where a washeteria-based drinking water system is affected by environmental and seasonal changes triggered by climate change and coastal erosion. By addressing both regional hydrology and community-specific challenges, the study highlights the critical interplay between glacial melt dynamics, permafrost thaw, and water infrastructure vulnerabilities. This study focused on identifying significant spatial and temporal DOC variations, seasonal sulfate patterns, and stable isotope variability across permafrost regions. Additionally, seasonal differences in Shishmaref’s water quality were hypothesized to result from freeze-thaw processes, impacting heavy metals, sulfate, and nitrate levels. The findings reveal distinct biogeochemical and hydrological patterns: DOC fluxes peaked in late summer and fall, particularly in regions with sporadic and "Thick Thin" permafrost, driven by permafrost thaw and organic matter mobilization. Sulfate concentrations exhibited pronounced seasonal variability, with higher levels during peak thaw (June-August) influenced by sulfate-rich soils, glacial melt inputs, and runoff dynamics. Stable isotope enrichment in δ2H and δ18O and declining d-excess during summer reflected evaporation, altered precipitation sources, and shifting hydrological pathways In Shishmaref, seasonal monitoring revealed elevated heavy metal concentrations, such as zinc and copper, during winter due to infrastructure-related leaching and sediment mobilization under freezing conditions. Increased calcium and sodium concentrations during winter were linked to freeze-thaw-induced mineral dissolution and salt deposition. Conversely, DOC and SUVA values showed minimal seasonal variation, indicating consistent organic matter sources. These findings underscore the urgent need for localized water management strategies and long-term monitoring to mitigate the impacts of climate change on Arctic hydrology and community water security. By drawing parallels between Arctic glaciers and the YRB with specific challenges in Shishmaref water quality, this study offers a comprehensive understanding of Arctic water quality dynamics and their broader implications for adaptation and sustainability.

Description

Thesis (M.S.) University of Alaska Fairbanks, 2025

Chapter 1: General introduction -- 1.1 Problem overview and motivation -- 1.2 Arctic glaciers and water quality challenges -- 1.3 The Yukon river basin and the ION project -- 1.4 Shishmaref: drinking water challenges in remote arctic villages -- 1.5 Research hypotheses and objectives -- 1.5.1 Research hypotheses -- 1.5.2 Research objectives -- 1.6 Thesis structuring and organization -- 1.7 References. Chapter 2: Effect of climate change on water quality of Arctic glaciers -- 2.1 Abstract -- 2.2 Arctic glacier system and their importance -- 2.3 Effect of climate change on arctic glaciers -- 2.3.1 Rate and extent of climate change on glaciers -- 2.3.2 Increase in glacial contamination and faster retreat rate -- 2.3.3 Consequences of increased glacier melt -- 2.4 Glacier system and its interaction with water bodies -- 2.4.1 Influence of climate change on glacial ecosystem -- 2.4.2 Direct and indirect climate change impacts on drinking water resources -- 2.5 Arctic contaminants and their fate and transport-chemical contaminants -- 2.5.1 Sources and mechanism of release of chemical pollutants from glaciers -- 2.5.2 Stability and pH-dependent speciation of pollutants -- 2.5.3 Heavy metal contamination from glaciers -- 2.5.4 Chemical of emerging concern (CECs) and persistent organic pollutants (POPs) in Arctic glaciers -- 2.5.5 Fate and transport of Arctic chemical contaminants -- 2.6 Microbial contaminants of Arctic glaciers -- 2.6.1 Bacteria -- 2.6.1.1 Microbial structure and diversity of microbes in Arctic glaciers -- 2.6.1.2 Adaptation mechanism of Arctic microbes -- 2.6.2 Viruses -- 2.6.2.1 Structure and diversity in Arctic glaciers viruses -- 2.6.2.2 Adaptation mechanism of arctic viruses -- 2.6.2.3 Potential disease carrying traits of the Arctic viruses -- 2.7 Implications and impacts of climate change-induced contamination of arctic contamination of Arctic glaciers -- 2.7.1 Contamination and its impacts on human health -- 2.7.2 Socio-economic impact of contamination of Arctic glaciers -- 2.7.3 Implication of Arctic contaminants on global policy change -- 2.7.4 Regulations and guidelines for emerging pollutants -- 2.8 Future implications of the study -- 2.8.1 Research gaps in arctic glacial study and modeling climate change effects -- 2.8.2 Corrective measures being applied for contaminant release -- 2.8.3 Pollutant tracing -- 2.9 Conclusion -- 2.10 References. Chapter 3: Multi-year water quality analysis of surface water from Yukon River watershed -- 3.1 Abstract -- 3.2 Introduction -- 3.2.1 Role of the ION project and YRITWC -- 3.2.2 Trends in DOC and sulfate: a permafrost perspective -- 3.2.3 Mechanisms behind DOC and sulfate variations -- 3.2.4 Historical and recent trends in DOC and sulfate -- 3.2.5 Implications for Indigenous communities and ecosystems -- 3.2.6 Contribution of the current five-year dataset -- 3.3 Materials and methods -- 3.3.1 Sample collection -- 3.3.2 Sample categorization -- 3.3.3 Laboratory analyses -- 3.3.4 Statistics and data analysis -- 3.4 Results -- 3.4.1 DOC results -- 3.4.2 Sulfate results -- 3.4.3 Stable isotopes results -- 3.5 Discussion -- 3.5.1 Variation in -- 3.5.2 Variation in sulfate -- 3.5.3 Variation in stable water isotopes -- 3.5.4 Overall trends -- 3.6 Conclusions -- 3.7 Recommendations for future study -- 3.8 References. Chapter 4: Status of water quality in remote Alaskan washeteria-fed community of Shishmaref -- 4.1 Abstract -- 4.2 Introduction -- 4.2.1 Study area: Shishmaref, Alaska -- 4.2.2 Water infrastructure and washeteria facilities in remote Alaska -- 4.2.3 Washeteria usage -- 4.2.4 Shishmaref drinking water issues -- 4.2.5 Similar Alaskan communities with washeteria based system -- 4.3 Methodology -- 4.3.1 Sample collection -- 4.3.2 Sample handling and preservation -- 4.3.3 Sample analysis -- 4.3.4 Data analysis and visualization -- 4.4 Results -- 4.4.1 Parameters by season -- 4.4.1.1 Physiochemical properties -- 4.4.1.2 Organic carbon levels -- 4.4.1.3 Ion concentrations -- 4.4.1.4 Nutrients levels -- 4.4.1.5 Trace metals -- 4.4.2 Parameters by water source type -- 4.4.3 Parameters by location -- 4.4.4 Parameters and their seasonal variation at common locations -- 4.4.5 Summary of pathogens in Shishmaref water -- 4.5 Discussion -- 4.5.1 Parameters by season -- 4.5.2 Anion and heavy metals concentration by water source type -- 4.5.3 Parameters by location -- 4.5.4 Parameters and their seasonal variation at common locations -- 4.6 Conclusion -- 4.7 Findings and recommendations -- 4.8 References.

Date

2025-08

Type

Thesis

Collections

Engineering