Research articles

This study—based on systematic testing of 30 different wheat crop models against field experiments—shows that many wheat models simulate yields well, but with reduced accuracy at higher temperatures. Extrapolation of the model ensemble response indicates that global wheat production will fall by 6% for each 1 °C increase in temperature.

Barrier islands represent about 10% of the world’s coastline and perform many services including coastal protection. A study now shows that islands exhibit a bistable response to environmental change. Improved understanding of these mechanisms can help to predict future transitions in barrier island state.

The viability of Pacific salmon populations could be compromised by the effects of climate change given their limited ability to adapt to increased temperatures.

Melt lakes form each year on the surface of the Greenland ice sheet but currently occur in regions with good subglacial drainage. An investigation of the impacts of the warming climate finds that the lakes will expand to higher elevations where ice-sheet drainage is not as efficient, which could result in enhanced lubrication and warming of the base of the ice.

Saturation state is shown to be the key component of marine carbonate chemistry affecting larval shell development and growth in two commercially important bivalve species.

In 2003, Europe experienced a summer heatwave that resulted in tens of thousands of deaths. This study uses observation and model data to show that human influence is increasing the probability of extremely hot summers in Europe, with events now expected to occur twice a decade, compared with predictions of twice a century in the early 2000s.

Acclimation, a form of physiological plasticity, is the capacity for organisms to physiologically adjust to temperature variation. Such changes can potentially reduce climate change impacts on animal populations. Research synthesizing the current state of knowledge about physiological plasticity in ectotherms shows that freshwater and marine animals seem to have a greater capacity for acclimation than terrestrial ones.

Climate models include many processes that may be simplified to save computational time. This work shows that model representation of upper atmosphere ozone can impact on the projected climate sensitivity.

Modelling studies of climate change impacts on phytoplankton typically consider individual properties, which ignores the complex nature of the marine environment. This work undertakes regional assessments using multiple properties, including interactions, and finds shifts of <20–300% in phytoplankton physiological rates.

The release of carbon from decomposing Arctic soils, following permafrost thaw, is a potentially important climate feedback. Research now shows how shrub cover protects permafrost carbon reservoirs. Manipulative experiments show that the loss of shrub cover leads to a transition of the tundra to waterlogged methane-emitting conditions.

The evidence that climatic conditions influence beliefs about anthropogenic climate change is mixed. Now research analyses the extent to which US state-level winter temperature anomalies influence the likelihood of perceiving warmer-than-usual temperatures, and the attribution of such temperatures to global warming. Results show that temperature anomalies have a strong influence on perception, whereas attribution is mainly driven by perceived scientific consensus and political orientation.

It is commonly assumed that pro-environmental behaviour can be triggered by offering an extrinsic reward. Now research shows that acting pro-environmentally elicits positive feelings and leads people to feel warmer. In experiments, people who learn they act in an environmentally friendly way feel good about themselves and perceive a higher room temperature than people who learn their behaviour is environmentally unfriendly.

A significant challenge for policies aiming to reduce carbon emissions from deforestation is the avoidance of international carbon leakage. Research now shows, however, that even globally implemented forest conservation schemes could allow another type of carbon leakage through cropland expansion into non-forested areas.

Parameterization of the temperature sensitivity of decomposition and efficiency of microbial carbon use represent large sources of uncertainty in soil carbon–climate responses. Now research shows that interactions between temperature, microbial biogeochemistry and mineral surface sorptive reactions could result in variable but weaker soil carbon–climate feedbacks compared with conventional substrate characterization with static temperature sensitivity.

Mass bleaching of coral caused by extreme thermal events is likely to intensify unless greenhouse-gas emissions are reduced. Modelling suggests that Pacific coral reefs will benefit from emissions reductions sooner than Caribbean reefs.

Much uncertainty in the response of soil organic carbon (SOC) to climate change relates to the relative effects of microbial priming and mineral protection. Now research indicates that although protected C provides an important constraint on microbial priming, it is not sufficient to prevent reduced SOC storage in most terrestrial areas.

Millions of people in China lack ready access to clean water and sanitation. Projected impacts of climate change may delay China’s progress towards reducing the burden of water-, sanitation- and hygiene-attributable infectious disease.

The linkages between the two goals of achieving universal access to modern energy and mitigating climate-altering emissions are assessed for the case of India.

This work investigates when the anthropogenic signal in regional sea-level rise will emerge from natural variability. Considering thermal expansion and changes in density and circulation, 50% of the global ocean will show an anthropogenic signal by the early-to-mid 2040s, whereas when all variables are considered, the anthropogenic signal will emerge in over 50% of the global ocean by 2020. This is substantially earlier than for surface air temperature and has little dependence on emissions scenarios.

Mean summer temperature in Eastern China has increased by 0.82 °C since the 1950s and five of the hottest summers have occurred since 2000. This study estimates anthropogenic influence to have caused a greater than 60-fold increase in the likelihood of extreme summer heat and projects that hot summers will continue to increase in frequency.