News & Comment

Extensive evidence reveals that Earth’s snow cover is declining, but our ability to monitor trends in mountain regions is limited. New satellite missions with robust snow water equivalent retrievals are needed to fill this gap.

Piece by piece, scientists are gathering evidence of the growing threat of wet snow avalanches in a warmer world.

Global snow coverage has declined substantially with anthropogenic warming, impacting biological, socio-economic and physical systems. This issue includes a suite of Comments, Reviews, Perspectives and original research documenting the importance of snow in the climate system, and how this may change with continued warming.

The current focus on the long-term global warming potential in climate policy-making runs the risk of mitigation options for short-lived climate pollutants being ignored, and tipping points being crossed. We outline how a more balanced perspective on long- and short-lived climate pollutants could become politically feasible.

Indigenous reindeer herding in the circumpolar North is threatened by multiple drivers of environmental and social changes that affect the sustainability of traditional family-based nomadic use of pastures. These impacts are exacerbated by indigenous peoples’ lack of voice in governance strategies, management and adaptation responses.

Bitcoin is a power-hungry cryptocurrency that is increasingly used as an investment and payment system. Here we show that projected Bitcoin usage, should it follow the rate of adoption of other broadly adopted technologies, could alone produce enough CO₂ emissions to push warming above 2 °C within less than three decades.

Scenarios have supported assessments of the IPCC for decades. A new scenario ensemble and a suite of visualization and analysis tools is now made available alongside the IPCC 1.5 °C Special Report to improve transparency and re-use of scenario data across research communities.

Climate change mitigation scenarios are finding a wider set of users, including companies and financial institutions. Increased collaboration between scenario producers and these new communities will be mutually beneficial, educating companies and investors on climate risks while grounding climate science in real-world needs.

Adjustments in the timing of seasonal events can seem like a relatively subtle impact of climate change, but one with potentially large ramifications for the health of ecosystems and the services they provide.

Biological communities beneath Antarctic ice shelves remain a mystery, hampering assessment of ecosystem development after ice-shelf collapse. Here we highlight major gaps in understanding of the patterns and processes in these areas, and suggest effective ways to study the ecological impacts of ice-shelf loss under climate change.

Climate change will almost certainly cause millions of deaths. Climate engineering might prevent this, but benefits — and risks — remain mostly unevaluated. Now is the time to bring planetary health research into climate engineering conversations.