Volume 8 Issue 11, November 2018

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.

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.

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.

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

Observations show that the Atlantic Meridional Overturning Circulation (AMOC) is slowing down, and this is predicted to continue in response to climate change. This isn’t the only change expected; tracing ocean circulation within a climate model now shows that the locations where water sinks to the deep ocean to feed the AMOC will also shift in the future.

Winter snow conditions influence which plants grow where in the Arctic. Now, a modelling study built on observational data of plant occurrence and snow conditions suggests that declines in snow cover will result in the loss of plant species.

This Perspective provides an overview of the snow–sea ice systems in the Arctic and Antarctic, offering insight on how current uncertainties can be reduced, and future challenges met, to improve understanding of polar climate change.

Using the ‘Can it? Has it? Will it?’ framework, this Review synthesizes current understanding on Eurasian snow–atmosphere coupling, outlining observational and modelling evidence for their dynamical connection and discussing possible changes in the future.

Snow albedo is impacted by the presence of light-absorbing particles, including black carbon and dust. This Review collates knowledge on the associated radiative forcing, discussing geographic variability, future impacts and challenges for reducing uncertainty.

Climate change, in combination with existing environmental issues, threatens the Mediterranean region. This Review highlights how climate change will interact with other factors to exacerbate five areas of risk unless there is mitigation and adaptation.

Projected sea-level rise and increased flooding threaten coastal agriculture. Gradual increases in soil salinity, but not inundation alone, are shown to correspond to increasing diversification into aquaculture and higher levels of internal migration.

The impact of coral bleaching and mortality is found to reduce aggression in resident butterflyfish. This is linked to the lower dietary percentage of preferred food, nutritionally rich Acropora coral, with a less nutritious diet influencing aggressive behaviour.

Climate and land-cover change can affect the summer and winter ranges and migration distances of migratory birds. Accounting for all of these factors, rather than just summer range as is typical, significantly increases the number of species under threat.

Arctic biodiversity patterns will be highly dependent on the evolution of snow conditions, according to simulation results that integrate observations of vascular plants, mosses and lichens over a range of Arctic landscapes.

During periods of photosynthetic inactivity, roots compete for nutrients with microbes and abiotic processes. Most ESMs neglect this competition, leading to large positive biases in annual N leaching and N₂O emissions estimates.

A combination of consumption-based emissions modelling and deliberative public workshops suggests that developing resource-efficient products will be an effective climate change mitigation strategy because it has both high emissions-reduction potential and wide-scale public approval.

The sinking of dense waters drives the Atlantic Meridional Overturning Circulation. As the climate warms, changes in ocean circulation, stratification and mixed-layer depth alter the regions in which this sinking occurs, with implications for global climate.