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The authors find that historical deforestation has substantially altered regional observed precipitation over the southern Amazon basin through inter-regional atmospheric moisture transport, which is underestimated in current climate models.

New global datasets of upper canopy vegetation respiration have become available and their impact on global carbon cycle models is unclear. Here, the authors show the implications of these parameterisations with a global gridded land model and report significantly higher global plant respiration estimates.

Although fluctuations in annual temperature have shown substantial geographical variation over the past few decades, which may be more difficult for society to adapt to than altered mean conditions, the time-evolving standard deviation of globally averaged temperature anomalies reveals that there has been little change.

An innovative assessment of climate change calculates the year in which ongoing warming will surpass the limits of historical climate variability. Three experts explain this calculation's significance compared with conventional approaches, and its relevance to Earth's biodiversity. See Article p.183

The authors assess the risk of overshoot beyond 1.5 °C warming, using three scenarios with minimal overshoot, brief overshoot and sustained overshoot. They show a risk of long-term Amazon dieback, which begins as early as 1.3 °C warming but is largely mitigated by reducing temperature below 1.5 °C.

Ongoing global warming is likely to cause tipping point thresholds to be passed, but an abrupt system change can still be avoided if the warming is reversed quickly relative to the timescale of the tipping element.

Climate feedbacks associated with wetland methane emissions and permafrost-thaw carbon release substantially reduce available carbon budgets to achieve temperature targets, suggest simulations with a climate–land-surface model system.

Emissions targets must be placed in the context of a cumulative carbon budget if we are to avoid dangerous climate change.

In 2005, there was a pronounced drought in the western Amazonian rainforest, which seems to have been associated with a period of unusually warm sea-surface temperatures in the North Atlantic. This event can be better understood with reference to the gradient in sea-surface temperatures across the equatorial Atlantic, of which the northern temperature anomalies are just a factor. By incorporating the effects of atmospheric aerosols into the model, the observed variations in this temperature gradient over the past century are reproduced, and it is predicted that the sea-surface conditions conductive to the droughts experienced in 2005 will become much more common.

Assessing potential future carbon loss from tropical forests is important for evaluating the efficacy of programmes for reducing emissions from deforestation and degradation (REDD). An exploration of results from 22 climate models in conjunction with a land surface scheme suggests that in the Americas, Africa and Asia, the resilience of tropical forests to climate change is higher than expected, although uncertainties are large.

A linear relationship between the sensitivity of tropical land carbon storage to warming and the sensitivity of the annual growth rate of atmospheric CO₂ to tropical temperature anomalies provides a tight constraint on the sensitivity of tropical land carbon to climate change.

An ensemble of experiments is used with a global climate model to assess the contribution of plant 'physiological forcing' to future changes in continental runoff. It is found that the effect increases simulated global mean runoff by 6 per cent when the concentration of carbon dioxide is doubled relative to pre-industrial levels; an increase that is comparable to that simulated in response to climate change caused by radiative forcing. This finding suggests that the risk of flooding may be greater than previously assumed under future global warming scenarios.

The effect of a cumulative emission of carbon on peak global mean surface temperature is better constrained than the effect of stabilizing the atmospheric composition. The approach is also insensitive to the timing or peak rate of emissions. Using carbon cycle models, it is shown that a trillion tonnes of carbon emissions (about half of which has already been emitted since industrialization began) will produce a most likely peak warming of 2 degrees Celsius.

Plants offset a large fraction of Earth’s carbon dioxide emissions, but estimating the size of this carbon sink relies on differing terrestrial-biosphere models. Combining multiple models with data has now reduced the uncertainty.

Accurately determining the warming associated with scenarios of greenhouse gas emissions remains an overarching aim of climate modelling. Research now shows that contemporary measurements significantly reduce uncertainty bounds and indicate that some more extreme warming predictions may be less likely.

Projections of temperature often focus on maximum warming levels, with variability less often considered. Investigating decadal variability in models shows those with higher equilibrium climate sensitivity also have a higher chance of super warming, and hiatus periods.

Equilibrium climate sensitivity—which remains the largest uncertainty in climate projections—is constrained to a ‘likely’ range of 2.2–3.4 K by taking into account the variability of global temperature about long-term historical warming.

A study using a newly developed framework shows how future peak temperature is related to cumulative emissions of long-lived greenhouse gases such as carbon dioxide and sustained emissions of shorter-lived species such as methane, and suggests an approach for limiting future warming to 2 °C above pre-industrial levels.

Climatic extremes can dramatically impact biodiversity. Now, research using comprehensive data on British butterflies reveals how drought and changes in habitat (area and fragmentation) interact to affect population stability.

More radiation generally increases vegetation photosynthesis, but field studies show that a given amount of diffuse radiation leads to more fixed carbon than direct radiation. Mercado and colleagues simulate the effect of late twentieth century increases in the diffuse radiation fraction, and find that the terrestrial carbon sink is enhanced by about 25% —paradoxically, reducing future anthropogenic pollution will reduce this diffuse radiation effect, creating a positive feedback to global warming.

Northern Hemisphere photosynthesis is thought to respond positively to temperature variations, yet the strength of this relationship may change over time. Here, using a combination of satellite data and models, the authors assess the temporal change of this relationship over the past three decades.

An ensemble of climate model simulations, as well as hydrological modelling and flood risk mapping, are used to show the role of anthropogenic warming on the extreme rainfall that caused the 2013/14 floods in southern England.

2024 witnessed record-high global vegetation greenness, far outpacing the previous high set in 2020. A total of 67.7% of vegetated land surfaces experienced greening, notably in Eurasian and tropical grasslands, and global croplands.

The dominant driver of variations in global land carbon sink remains unclear. Here the authors show that the seasonal compensation of temperature effects on land carbon sink in the Northern Hemisphere could induce a global water dominance.

Vegetation change over the past two decades has limited the decline in global water availability by enhancing rainfall over evapotranspiration, according to analysis of observation-based atmospheric moisture transport data.

Modelling suggests that the Montreal Protocol may be mitigating climate change by protecting the land carbon sink, as well as by protecting the ozone layer and reducing greenhouse gas emissions.

The future of terrestrial systems is influenced by their past, but this carryover effect is rarely quantified. Here, the authors provide the first quantitative evidence that a greener spring begets a greener summer and autumn, and that this carryover effect is even stronger than climate drivers.

The authors test for temperature dependency of ecosystem respiration rates across globally distributed eddy covariance sites, revealing consistent temperature thresholds where ecosystem metabolism changes.

Land-based mitigation for meeting the Paris climate target must consider the carbon cycle impacts of land-use change. Here the authors show that when bioenergy crops replace high carbon content ecosystems, forest-based mitigation could be more effective for CO₂ removal than bioenergy crops with carbon capture and storage.

Monsoon systems have strong impacts on precipitation and food security over large areas of the world. Here, the authors show that plant responses to rising CO₂ concentrations in the atmosphere play a key role in modulating seasonal rainfall and water resources over global land monsoon regions.

The ratio of plant transpiration to total terrestrial evapotranspiration (T/ET) captures the role of vegetation in surface–atmosphere interactions. An emergent constraint approach strongly increases existing model T/ET estimates with implications for river flows.

The northern temperate carbon sink is estimated to increase by 0.64 PgC each year for each increase in atmospheric CO₂ concentrations by 100 ppm, suggests an analysis of data from field experiments at 7 sites constraints.

This Perspective considers the extent to which early action to reduce emissions of short-lived climate pollutants, such as methane and black carbon, would help to limit global warming. Although decreasing emissions of these pollutants would have short-term benefits, simultaneous CO₂ reductions are urgently required to mitigate the risk of dangerous climate change in the longer term.

Including passive CO₂ uptake as an anthropogenic removal in greenhouse gas accounting systems could undermine the Paris Agreement; measures to address this include acknowledging the need for Geological Net Zero and disaggregated accounting for carbon sinks.

Data and model-based evidence suggests that future weather patterns will be more complex than simply those of the past plus background warming. Now research offers physical explanations of how short-term climate variability might adjust.

Global greening continued into 2023, reaching near-record values that were dominated by regional enhancement in the mid-western USA, Europe, northern Australia and parts of equatorial Africa. In contrast, climatic events contributed to browning signals in Russia, Canada, Mexico and tropical drylands.

Research on the ecological impacts of drought has predominantly focused on the scarcity of water supply, often overlooking divergent ecosystem water demands across vegetation types, regions, and time. These diverse ecosystem water demands need to be incorporated into an effective ecological drought monitoring and assessment framework.

Efforts to control climate change require the stabilization of atmospheric carbon dioxide concentrations. An assessment of the trends in sources and sinks of atmospheric carbon dioxide suggests that the sinks are not keeping up with the increase in carbon dioxide emissions, but uncertainties are still large.

A study of how temperature and water availability fluctuations affect the carbon balance of land ecosystems reveals different controls on local and global scales, implying that spatial climate covariation drives the global carbon cycle response.

Rainfall variability in Eastern Africa is associated with considerable social and environmental impacts, including threats to water, energy and food security. This Review outlines the drivers of this rainfall variability, their corresponding impacts, and potential future changes with anthropogenic warming.

Emergent constraints can be an evaluation tool for Earth System Models. This Perspective discusses emergent constraints, how they should be assessed, and when these statistical relationships can be confirmed and used to improve understanding of the changing climate system.

The winter of 2013–14 witnessed severe flooding across much of the UK putting pressure on policy makers to improve future planning for periods of torrential rainfall. This Perspective puts the flooding in the context of historical records, critically examines a range of potential causes, and sets out research directions needed to achieve a definitive assessment on the possible human contribution to the flooding.

Estimates of global dryland changes are often conflicting. This Review discusses and quantifies observed and projected aridity changes, revealing divergent responses between atmospheric and ecohydrological metrics that can be explained by plant physiological responses to elevated CO₂.

Global warming accelerated canopy senescence in July, but slowed it in late summer and early fall in the Northern Hemisphere, according to an analysis of Normalized Difference Vegetation Index satellite retrievals over 1982–2018