Report warns temperature overshoot could cause lasting damage to snow and ice

What you need to know

• The report, Overshoot and the Cryosphere: Averting Global Meltdown, was produced by the International Cryosphere Climate Initiative in coordination with UNEP. Its findings concern connected parts of the cryosphere, including mountain glaciers, polar ice and frozen ground. 13
• The consequences of ice loss can endure after temperatures fall. The report says glacier loss and the resulting contribution to sea-level rise would persist even if temperatures later returned to 1.5°C. 134
• Some losses may be partly recoverable: the report says sea ice and glaciers could regrow over decades to centuries if temperatures return to 1.5°C or lower. This does not mean all cryosphere damage would be reversed. 14
• The companion State of the Cryosphere 2026 report says Switzerland lost 20% of its glacier ice in the past five years. It also identifies water shortages and mountain hazards among the impacts associated with ice loss. 23
• The proposed response combines deep emissions reductions with carbon dioxide removal. The sources present this as a way to limit overshoot and slow or partly reverse some losses, not as an outcome already achieved. 14

Why this matters

Cryosphere change is linked in the reports to rising sea levels, water shortages and mountain hazards. Because some effects could persist after temperatures decline, preventing further warming-related losses matters even if the world later returns below 1.5°C. 123

What happens next

The pathway identified by the report depends on deep emissions cuts and a swift return to 1.5°C or lower. The sources do not report that this has been achieved; they describe it as a condition for limiting further damage and enabling some recovery. 14

What we know

• The report was produced by the International Cryosphere Climate Initiative in coordination with UNEP and brings together more than 80 polar and mountain scientists. 13
• Its findings cover ice sheets, glaciers, permafrost, sea ice and polar oceans, with some projected impacts described as irreversible. 134
• The companion 2026 report reports a 20% loss of Switzerland’s glacier ice over the past five years. 23
• A return to 1.5°C or lower could permit some sea-ice and glacier regrowth over decades to centuries, according to the report. 14

What we don't know

• The supplied reporting does not set out how projections differ across varying levels and durations of temperature overshoot. 134
• It does not establish how feasible or sustainable the proposed scale of carbon dioxide removal would be. 14
• The reporting leaves unresolved which ice losses can still be avoided and which are already committed under current warming. 1234

Read the reporting

This WildNews briefing synthesises and summarises reporting from the sources below. WildNews did not produce the original reporting. Learn more about how we use AI