Volume 9 Issue 11, November 2019

Future emissions scenarios for the IPCC Sixth Assessment Report should explore the carbon budget space in a systematic manner, which would be robust to the updates of latest climate science, so that policy implications can be adequately assessed.

The consequences of global warming will be dire, but the full extent of these effects on society is unknown and includes uncertainties. Research now suggests that how scientists communicate about the uncertainty over such climate change impacts can influence the public’s trust and acceptance of this information.

Predicting coral bleaching is critical to better manage and preserve coral reefs from global warming. An impressive coordination of surveys across oceans now offers new metrics to help to predict coral bleaching events on a global scale.

The effects of global warming are felt earlier in Arctic regions than elsewhere in the world. Now research shows that Arctic marine food webs can adapt to climate change — but the study authors warn that this impression of resilience may be false in the long term.

Warming in the Arctic is causing soils to decompose more rapidly, even during winter. Now, estimates of winter carbon dioxide loss indicate that it can offset carbon gains during the growing season, meaning that the region is a source of carbon.

Observations reveal recent Arctic warming, but future societal impacts are poorly understood. Now research identifies potential abrupt thaw-driven soil moisture shifts, with consequences for northern development including more intense wildfires and rainfall.

Ecosystem response to climate change will vary in amplitude and dynamically, which may not be captured in current experimental design. This Perspective presents experimental design improvements to better predict responses and thus facilitate understanding of future impacts.

Transformation of the land sector is required to meet the Paris Agreement goal of limiting warming to 1.5 °C. Here, modelled emission pathways and mitigation strategies are reviewed. A land-sector roadmap of priority measures and key regions is presented.

Increasingly, financial institutions will be exposed to climate risks that will exacerbate the negative economic impacts of climate change. An agent-based integrated assessment model is used to analyse climate impacts on the global banking system, finding an increase in banking crises and public bailout costs.

Global warming projections exhibit a contracted intertropical convergence zone (ITCZ) and an expanded Hadley cell. Here, equatorial Pacific warming is shown to contract seasonal ITCZ migration and counteract Hadley cell expansion, leading to an equatorward shift in the Asian subtropical monsoon.

Ocean warming and acidification will affect the structure and bioavailability of biomolecules. The toxic form of two neurotoxins will increase with climate change, presenting an ecotoxicology risk with global hotspots as exemplified by saxitoxin toxicity in Alaskan butter clam.

Improved predictions of coral bleaching are critical. In a coordinated global survey effort during the 2016 El Niño, time-series patterns of peak hot temperatures, cool period durations and temperature bimodality were found to be better predictors of coral bleaching than common threshold metrics.

Winter warming in the Arctic will increase the CO₂ flux from soils. A pan-Arctic analysis shows a current loss of 1,662 TgC per year over the winter, exceeding estimated carbon uptake in the growing season; projections suggest a 17% increase under RCP 4.5 and a 41% increase under RCP 8.5 by 2100.

Permafrost thaw due to rising temperatures will impact soil hydrology in the Arctic. Abrupt changes in soil moisture and land–atmosphere processes may alter the bearing capacity of soil and increase susceptibility to wildfires, with consequences for adapting engineering systems in the region.

This study shows that expressing uncertainty about best- and worst-case effects of climate change on sea-level rise increases trust in climate scientists and message acceptance but not when the full extent of inevitable uncertainty due to unpredictable storm surges is also acknowledged.

The resilience of a marine food web to climate change is investigated through a combination of multiple and nested species interactions. The Kongsfjorden food web adapts and maintains core ecological processes during change, with increasing dominance of Atlantic species boosting resilience.

Climate change is expected to impact river flows. Here, it is shown that plant physiological responses to increased CO₂, rather than atmospheric changes, are the primary drivers of mean, peak and low flows throughout the tropics.

Predicting mortality in forests is challenging because its underlying causes are spatially varied and not well known. Reduced resilience detected from remotely sensed time series of vegetation dynamics can serve as an effective early warning signal to indicate the potential for forest mortality.

The subnivium—the space between snowpack and the ground—is an insulating refuge from winter cold. This study predicts that climate warming decreases the subnivium’s seasonal duration yet increases snow-free days with frozen ground, making winter functionally colder for subnivium-dependent life.