Snow and ice-related hazards, risks, and disasters: Facing challenges of rapid change and long-term commitments

Snow and ice constitute the cryosphere on Earth and influence human activities at various scales of time and space. Through their proximity to phase-change thresholds, they are strongly linked to climatic conditions and presently subject to rapid changes induced by ongoing trends of global warming. Hazards, risks, and disasters related to snow and ice not only result from direct impacts on humans and their infrastructure by, for instance, snow avalanches, floods from glacial lakes, or accelerated erosion of permafrost coasts, but they are also a consequence of the expansion of human activities into previously avoided dangerous regions, such as new shipping routes in the polar ocean, or tourist installations in cold mountains that are becoming ice-free. The loss of goods and benefits from reducing or even vanishing cryosphere components constitutes serious hazards to human well-being through, for example, diminishing meltwater supply in high-mountain rivers during dry seasons or rising global sea level. As ongoing changes in cases involve long-term commitments, corresponding future consequences are inevitable and irreversible at societal timescales. Further protection, mitigation, and adaptation procedures, combined with modern observational technologies will be required to anticipate, monitor, and deal with the challenges created by complex and highly interconnected snow- and ice-related geo- and ecosystems under the conditions of growing disequilibrium.