The Arctic in a Changing Climate and its Global Impacts

The session will follow the presentation of the WMO State of the Global Climate. It will focus on the Arctic and, by extension, polar changes in the changing climate and their regional and global impacts.

In 2024, WMO adopted four high level ambitions on the cryosphere. These are serving as catalyst for engagement and action on advancing the development of systems and services to support the international community in addressing global impacts from changes in the cryosphere (e.g. uncertainties in the future of water availability, of sea level rise, on the amplification of natural hazards in polar and mountain regions, on the release of carbon in the atmosphere from permafrost thaw).

The Arctic Climate Change Update 2024 of the Arctic Monitoring and Assessment Programme (AMAP) of the Arctic Council provides an update on some of the rapid and unprecedented changes occurring in the Arctic climate system. The report builds on previous assessments, incorporating four additional years of data since the previous AMAP climate update that reveal new record-setting trends in air and permafrost temperatures, wildfires, and sea ice minima. These latest observations highlight the increasing severity of Arctic climate change, with significant implications for the global climate system. The report also explores future projections for the region, emphasizing the urgent need for mitigation measures.  

A central theme of the update is the emergence of "extreme extreme" events—climatic occurrences that surpass any previously recorded extremes. Examples from summer 2023, including record land temperatures, early snow melt, extreme sea temperatures, and wildfires, underscore the unpredictability of these events. The report suggests that these new patterns are a result of interacting processes within the Arctic's physical and biological systems, placing the region in an unprecedented state.    

The increasing intensity and frequency of wildfires across the Arctic, driven by warmer and drier conditions, are another major concern. The expansion of vegetation due to permafrost thaw is contributing to this trend, and the report underscores the importance of integrating Indigenous knowledge to improve understanding of wildfire ignition sources. 

Updates on the cryosphere, including permafrost, sea ice, and snow, further illustrate the ongoing transformation of the Arctic. The report also examines the impacts of climate change on the Arctic freshwater system and ocean acidification, highlighting the accelerated pace of change. Projections show that Arctic Ocean acidification is likely to intensify, but strong mitigation efforts could help slow the pace of these changes and limit ecosystem damage.  

Finally, the update addresses the evolving understanding of Arctic and mid-latitude weather linkages, with implications for weather patterns that affect millions of people globally.