Research Briefing

Analysis of high-resolution climate models reveals a substantial reduction in global oceanic kinetic energy under global warming. This reduction of oceanic kinetic energy is mainly due to weakened mesoscale eddies in the deep ocean.

The greenhouse gas abatement costs for two forest restoration methods — natural regeneration and plantations — are estimated by integrating observations on the costs of reforestation projects with other biophysical and economic data. This analysis reveals that a mix of reforestation methods offers greater potential to mitigate climate change at low cost than previously estimated.

The growth and yield of 3,652 wheat genotypes under past and simulated future climates indicate that adaptation to a wide range of environments will decrease by 8.7% for each 1°C of warming. Thus, future breeding strategies must deliver genetically diverse elite lines that can adapt to the warmer conditions and likely more diverse weather scenarios caused by climate variance.

Observational data suggest a dramatic increase in the salinity contrast between the Atlantic and Pacific oceans over the course of the past half-century. Ocean dynamical processes driven by winds and warming, in addition to surface freshwater fluxes, make important contributions to basin-scale changes in ocean salinity.

Analysis of 393,139 forest inventory plots shows that increased biodiversity weakens the sensitivity of spring leaf-out dates to warming, possibly owing to diversity-driven changes in root depth and soil biogeophysical and biogeochemical processes, among potential mechanisms.

In a global-scale study, we investigated the contribution of individual and multiple global change stressors to soil carbon variables, which revealed that an increasing number of global change stressors will reduce the amount of carbon in soils, challenging their capacity to mitigate climate change.

A comprehensive analysis of observations and model simulations finds that future global mean warming is likely to be larger than previously thought, and that limiting global warming to well below 2°C will be more difficult than previously anticipated.

Our multi-model analysis of international shipping shows the potential for decreasing global annual emissions in the coming decades, up to a reduction of 86% by 2050. Drop-in biofuels, renewable alcohols and green ammonia stand out as the main substitutes for conventional maritime fuels.

When the temperature increases, so do the energetic requirements of species. We find that the energetic stress caused by increases in temperature pushes fish species to consume the first prey they encounter to fulfil their immediate needs, rather than focusing on more energetically rewarding prey. This behaviour increases the vulnerability of communities to climate change.

Analysis of patent data from 1990 to 2019 reveals a global decline in the invention and international diffusion of high-quality methane-targeted abatement technologies (MTATs) from 2010 to 2019. Moreover, there is a mismatch between where MTAT inventions are concentrated and the countries or regions expected to have most growth in future methane emissions.

Groundwater recharge replenishes aquifers and enables them to sustain irrigated agriculture and household water access, but the sensitivity of recharge to climate change remains unclear. Our analysis of global recharge rates demonstrates their sensitivity to climatic conditions, implying that amplified and nonlinear impacts of climate change on recharge rates are likely.

In a changing climate, tree trunks serve as crucial refuges for animals, particularly ectotherms, seeking to escape extreme climatic conditions. Therefore, while climate change could generally promote population growth among ectotherms, deforestation could reverse these positive effects in some populations or exacerbate the negative impacts of climate change in others.

Tropical instability waves (TIWs) are an important component of the equatorial Pacific climate. An analysis of satellite observations, in situ measurements and ocean circulation models indicates that TIW activity has intensified in the central equatorial Pacific by approximately 12 ± 6% per decade since the 1990s.

Aerial photographs collected during mapping expeditions of Greenland’s coastline represent the only robust, widespread observations of twentieth-century glacier change for this vast island. We use this unique dataset to document the response of Greenland’s peripheral glaciers to climate change over approximately 130 years, providing enhanced confidence that recent changes are exceptional on a century timescale.

Assessing progress and gaps in climate adaptation is a key policy concern, and also raises scientific challenges around which metrics should be used and who should assess progress. A structured expert judgement using local case studies shows that, for coastal areas, today’s global adaptation is halfway to achieving the full adaptation potential.

An insight into the global patterns of marine heatwaves from the surface to depths of 2,000 m reveals that subsurface events are more intense and long-lasting than surface ones. Biodiversity exposure to the effects of marine heatwaves is higher at depths of 50–250 m, suggesting that subsurface biodiversity could be at considerable risk.

A multi-model analysis shows that the incorporation of advances in damage functions — namely growth effects — substantially increases the social cost estimates of methane and nitrous oxide, although uncertainty remains.

Emission savings from three circular economy strategies aiming to close, slow and narrow China’s bulk material loops have been analysed using an integrated model. This analysis highlights that material recycling delivers substantial emission cuts, but demand reduction is equally crucial for decarbonizing bulk materials.

Weather station records are too short and sparse to effectively detect the signature of climate change in Antarctica. Using the isotopic composition of ice cores as a temperature proxy suggests that Antarctica is warming faster than the global average temperature and expectations from climate models for the region.

A network of more than 100 researchers tracked trees for up to 30 years in forest plots across South America, enabling estimation of the impacts of record temperatures and drought on carbon dynamics. The carbon sink in these forests ceased during the 2015–2016 El Niño, with drier forests losing the most carbon.