Suppressed Basal Melting in Eastern Thwaites Glacier Grounding Zone: Implications for Sea Level Rise
Suppressed Basal Melting in Eastern Thwaites Glacier Grounding Zone: Implications for Sea Level Rise
Thwaites Glacier is a significant contributor to sea-level rise, as it is one of the fastest-changing ice-ocean systems in Antarctica. Its catchment area includes much of the ice sheet that is grounded below sea level, making it susceptible to rapid and irreversible ice loss that could significantly increase global sea levels. However, the extent and rate of ice loss are set by unknown ocean conditions and basal melting within the grounding-zone region where Thwaites Glacier first goes afloat.
Recent observations from a hot-water-drilled access hole reveal that the grounding zone of Thwaites Eastern Ice Shelf (TEIS) is characterized by a warm and highly stable water column with temperatures substantially higher than the in situ freezing point. Despite these warm conditions, the ice-ocean boundary layer actively restricts the vertical mixing of heat towards the ice base, resulting in strongly suppressed basal melting. These findings suggest that the current model of ice-shelf basal melting used to generate sea-level projections cannot reproduce observed melt rates beneath this critically important glacier.
Marine-based ice sheets like Thwaites Glacier are particularly sensitive to warming climates, and their fate is dynamically linked to the fate of the floating ice shelves at their seaward margin. These ice shelves buttress the ice sheet and control the flow of grounded ice into the ocean. Over recent decades, elevated ocean-driven basal melting has triggered rapid thinning of many West Antarctic ice shelves, reducing the strength of ice-shelf buttressing and increasing the rate of ice-shelf mass loss.
Thwaites Glacier is especially susceptible to marine ice-sheet instabilities due to its grounding on a retrograde bed that deepens inland. Its grounding line has retreated 14 km inland since the late 1990s, and in some regions, is retreating by up to 1.2 km per year at present. The poorly understood ocean conditions and basal melt rate in the constantly evolving grounding-zone region make it difficult to predict the rate and extent of ice loss from Thwaites Glacier and whether it will proceed irreversibly.
These findings have significant implications for sea-level projections, as a rapid and possibly unstable grounding-line retreat may be associated with relatively modest basal melt rates. A complete collapse of Thwaites Glacier within centuries could contribute 65 cm to the global sea level, and the full destabilization of the main glaciers in the Amundsen Sea sector would contribute 3 m to the global sea level over thousands of years. Therefore, it is crucial to continue monitoring the grounding-zone region of Thwaites Glacier and to better understand the complex interactions between ice, ocean, and atmosphere.
The Impact of Human Activity on Ecosystems: A Comprehensive Study
Biodiversity Preservation and Sustainable Practices: Understanding the Impact of Human Activity on the Environment
This article presents a comprehensive study on the impact of human activity on the Earth's ecosystems, including deforestation, overfishing, climate change, and pollution. Learn about the importance of preserving biodiversity and ecosystems for a sustainable future.
Understanding the impact of human activity on the environment is crucial for the preservation of biodiversity and the implementation of sustainable practices. Read this article for a comprehensive study on the topic.
The article provides an overview of the impact of human activity on the Earth's ecosystems. The introduction highlights the need for understanding the negative effects of human activity on the environment and the importance of preserving biodiversity and ecosystems.
The Impact of Human Activity on the Earth's Ecosystems:
human activity has negatively impacted the environment, including deforestation, overfishing, climate change, and pollution. The sub-sections provide detailed information on each of these topics.
a. Deforestation and Habitat Destruction:
This sub-section provides an overview of deforestation and its impact on the environment. It also suggests measures that can be taken to minimize deforestation and its impact on the environment.
b. Overfishing and Marine Ecosystem Degradation:
This sub-section provides an overview of overfishing and its impact on the marine ecosystem. It also suggests measures that can be taken to minimize overfishing and the degradation of the marine ecosystem.
c. Climate Change and Global Warming:
This sub-section covers the impact of climate change and global warming on the environment. It also suggests measures that can be taken to reduce greenhouse gas emissions and mitigate the effects of climate change.
d. Pollution and its Impact on the Environment:
This sub-section covers the impact of pollution on the environment, including air and water pollution. It also suggests measures that can be taken to minimize pollution and its impact on the environment.
The Importance of Preserving Biodiversity and Ecosystems:
This section emphasizes the importance of preserving biodiversity and ecosystems for the sustainable future of our planet. The sub-sections provide an overview of sustainable practices
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