Kirkham (2026) The future of glaciers and ice sheets and the importance of global mean temperature targets and international climate negotiations

Identification

• Journal: Elsevier eBooks
• Year: 2026
• Date: 2026-01-01
• Authors: James D. Kirkham
• DOI: 10.1016/b978-0-323-85242-5.00062-2

Research Groups

International Cryosphere Climate Initiative, Pawlet, VT, United States

Short Summary

This paper synthesizes the current understanding of cryosphere changes under different global warming scenarios, emphasizing how international climate policy efforts and global mean temperature targets critically determine the extent and speed of future cryosphere loss and its associated impacts. It highlights that while some long-term loss is inevitable, deep emissions reductions are crucial to limit the burden on society.

Objective

• To evaluate the future of the cryosphere (mountain glaciers, ice sheets, permafrost, sea ice) under various global mean temperature targets and to underscore the importance of international climate negotiations and emissions reductions in mitigating cryosphere loss and its impacts.

Study Configuration

• Spatial Scale: Global, encompassing mountain glaciers worldwide, the Greenland and Antarctic ice sheets, Arctic permafrost, and polar oceans.
• Temporal Scale: Decadal to centennial, focusing on projections up to 2100 and beyond for long-term impacts (e.g., multi-century sea-level rise).

Methodology and Data

• Models used: This paper is a synthesis of existing scientific literature. It draws upon projections from various climate models and cryosphere models developed by the broader scientific community, rather than presenting new model runs.
• Data sources: Synthesizes findings from existing observational datasets (e.g., historical temperature records, cryosphere monitoring) and reanalysis products, as well as projections from climate model intercomparison projects and specialized cryosphere modeling studies. References to "Copernicus and WMO, 2025" indicate reliance on contemporary climate monitoring reports.

Main Results

• Accelerating cryosphere losses are currently observed, with impacts intensifying as global temperatures rise.
• Every 0.1 °C of warming avoided significantly reduces the impacts of cryosphere loss and the scale of necessary adaptation.
• The world's current warming trajectory of approximately 2.7 °C above pre-industrial levels by 2100 will lead to widespread deglaciation of mountain glaciers, significant changes to polar sea ice, extensive permafrost thaw, and the long-term collapse of large ice sheet regions, driving multi-meter sea-level rise over centuries.
• Even if warming is limited to 1.5 °C above pre-industrial levels, roughly half of the world's glaciers are still projected to be lost by 2100, Arctic permafrost area will reduce by about 25%, and sea-level is expected to rise by several meters over the coming centuries.
• The speed and magnitude of global greenhouse gas emissions reductions are the primary determinants of future cryosphere loss and the associated societal impacts and adaptation requirements.

Contributions

• This article provides a comprehensive synthesis of the state of cryospheric science in the context of international climate policy and temperature targets, highlighting the critical link between emissions pathways and the future of Earth's ice.
• It quantifies the differential impacts of various warming scenarios on key cryospheric components, offering a clear scientific basis for the urgency of ambitious climate action.
• It underscores the "every tenth of a degree matters" message, providing a crucial perspective for policymakers and the public on the benefits of limiting warming as much as possible.

Funding

Not specified in the provided text.

Citation

@article{Kirkham2026future,
  author = {Kirkham, James D.},
  title = {The future of glaciers and ice sheets and the importance of global mean temperature targets and international climate negotiations},
  journal = {Elsevier eBooks},
  year = {2026},
  doi = {10.1016/b978-0-323-85242-5.00062-2},
  url = {https://doi.org/10.1016/b978-0-323-85242-5.00062-2}
}