Removing CO2 from the atmosphere using land-based mitigation strategies is central to nearly every country’s net-zero target.
To mitigate global climate change, land-use and land-management sectors need to reduce greenhouse gas emissions and remove carbon from the atmosphere.
Protecting ecosystems and dedicating more land to nature-based solutions and climate-smart agricultural practices are promising ways to do so.
To date, there has been little work looking at where, specifically, these strategies may be in conflict with one another.
Our research, published in Global Change Biology, assesses opportunity costs among 19 different land-use strategies for climate mitigation.
We find that roughly 8.5bn hectares of land around the globe are suitable for at least one land-based mitigation strategy – representing about 60% of the Earth’s land surface.
However, almost 40% of this land is suitable for more than one mitigation strategy, presenting decisionmakers with a choice as to which strategy or strategies they should deploy.
Land-based mitigation
To achieve global climate targets in a timely manner, some studies call for up to 10% of Earth’s terrestrial surface to undergo a land-cover change.
But is there actually enough land to make this happen? And if there is, how can projects be scaled up strategically to maximise the mitigation benefits while minimising negative impacts on humans and biodiversity?
Disciplinary silos and practical uncertainties have previously made these questions hard to answer.
For instance, nature-based solutions, including habitat conservation and restoration, are often differentiated from other climate-motivated land-use practices, such as bioenergy cropping and afforestation. Yet, both types of practices can have significant trade-offs for biodiversity and for agriculture.
Although controversial, these types of climate-specific land-use changes are proposed in many national climate mitigation plans. As these plans are put in motion, the trade-offs that could result from increasing the land dedicated to certain strategies over others need careful consideration.
In our study, we assess land-use opportunity costs across a portfolio of 19 different strategies for climate mitigation.
Broadly speaking, these strategies can be classified into four main approaches to mitigation: maintaining or protecting ecosystems, modifying forestry or agricultural management practices, restoring ecosystems and converting land to increase biomass.
Of these, certain approaches and strategies can be used to avoid emissions, while others can be used to sequester carbon.
Among the strategies we studied are the protection and restoration of forest, wetland, peatland and grassland habitats, various approaches to climate-smart cropland and forestry management (including biochar and silvopasture), bioenergy cropping with carbon capture and storage and afforestation.
We used global datasets on forests, croplands and other habitat types alongside data on environmental conditions such as temperature to estimate how much of the global land area is suitable for each strategy.
Then, we created global maps at a one kilometre resolution that identify areas that could be considered for these measures.
Land potentials
We find that some strategies had large regions of suitability.
For example, deforestation and other types of habitat loss are a large contributor to greenhouse gas emissions from the land-use sector. Maintaining grassland and forest habitat types to prevent losses can be done anywhere that such loss is occurring.
Maintaining the carbon stored in ecosystems that are currently unprotected accounts for more than 3bn hectares of the land we estimate as suitable for land-based climate mitigation – equal to about 20% of the Earth’s land surface.
Other strategies, including peatland restoration and silvopasture, had much more restricted areas of suitability across the globe.
For peatland restoration, priority areas are primarily distributed in the boreal zone – the high-latitude northern hemisphere, just south of the Arctic. Cropland expansion has led to widespread peatland loss in this region over the past several decades.
For silvopasture – a type of livestock farming that integrates tree cover with grazing – suitability is primarily constrained by environmental limits on tree growth. Here, factors such as water availability determine in which regions traditional pastoral systems could be converted to silvopasture.
The figure below shows the 19 mitigation strategies we studied and the area of the Earth that is suitable for each, in millions of hectares. The three maps on the right show example distributions for (from top to bottom) enhanced chemical weathering, bioenergy with carbon capture and storage (BECCS) and integrating trees into croplands.
Conflict potential
When summing the suitable area across all the 19 strategies we examined, we find that a huge area of Earth – almost 60% of its land surface – is theoretically suitable for land-based climate mitigation.
However, the majority of this area captures regions where more than one mitigation strategy is suitable.
In some cases, these overlapping land potentials involve mitigation strategies that can be deployed jointly, such as increasing the carbon stored in soils at the same time as increasing the carbon stored in aboveground biomass.
One example of this is the potential to collectively implement enhanced chemical weathering and improved plantation management, which have a combined land suitability of 348m hectares.
(Enhanced chemical weathering involves spreading ground-up silicate rocks onto farms or other land. This speeds up natural chemical processes and removes CO2 from the atmosphere, while also improving crop yields.)
However, suitable areas for compatible strategies were rare, compared to the area where conflicts between strategies could occur.
For instance, large portions of the US, Europe and China are suitable for both ecosystem restoration and climate-smart agriculture.
In these regions, societies face a choice between restoring grassland, forest and wetland habitats, or continuing to manage the land for agriculture, where climate-smart practices could still be implemented to decrease greenhouse gas emissions or sequester more carbon.
Because the choice between large-scale restoration and climate-smart agriculture may involve a trade-off between restoring habitat for biodiversity or maintaining land use for people, we avoid making any recommendations about which land-use practices to implement.
Rather, our paper highlights areas where these trade-offs could occur – places in which large-scale top-down planning could conflict with local priorities for land-use.
More research is needed to map local constraints and management costs so that the choice between mitigation strategies aligns local needs with national and global targets for climate mitigation.
Opportunity costs
So, with these potential overlaps and conflicts, is there enough land to meet climate targets?
The answer is yes, in theory – the summed area we estimate as suitable for climate mitigation is more than double the amount of land that has been pledged for transformation by UN member countries in their pledges to meet the goals of the Paris Agreement.
However, the pace of on-the-ground implementation lags far behind the degree of land-use change needed to limit warming by 2050. And high-level constraints, such as meagre financing or a lack of political incentives, will continue to stall progress.
Given these choices and constraints, land-use opportunity costs should be considered when planning policies that may incentivise certain types of mitigation practices that could inadvertently displace opportunities for others.
As plans to reach net-zero continue to develop, the atlas of maps for mitigation practices – and the exploration of opportunity costs – can guide pathways for scaling up land-based mitigation to address climate change.
The post Guest post: The conflicting practices in using land to tackle climate change appeared first on Carbon Brief.
Guest post: The conflicting practices in using land to tackle climate change
Drought and heatwaves occurring together – known as “compound” events – have “surged” across the world since the early 2000s, a new study shows.
Compound drought and heat events (CDHEs) can have devastating effects, creating the ideal conditions for intense wildfires, such as Australia’s “Black Summer” of 2019-20 where bushfires burned 24m hectares and killed 33 people.
The research, published in Science Advances, finds that the increase in CDHEs is predominantly being driven by events that start with a heatwave.
The global area affected by such “heatwave-led” compound events has more than doubled between 1980-2001 and 2002-23, the study says.
The rapid increase in these events over the last 23 years cannot be explained solely by global warming, the authors note.
Since the late 1990s, feedbacks between the land and the atmosphere have become stronger, making heatwaves more likely to trigger drought conditions, they explain.
One of the study authors tells Carbon Brief that societies must pay greater attention to compound events, which can “cause severe impacts on ecosystems, agriculture and society”.
Compound events
CDHEs are extreme weather events where drought and heatwave conditions occur simultaneously – or shortly after each other – in the same region.
These events are often triggered by large-scale weather patterns, such as “blocking” highs, which can produce “prolonged” hot and dry conditions, according to the study.
Prof Sang-Wook Yeh is one of the study authors and a professor at the Ewha Womans University in South Korea. He tells Carbon Brief:
“When heatwaves and droughts occur together, the two hazards reinforce each other through land-atmosphere interactions. This amplifies surface heating and soil moisture deficits, making compound events more intense and damaging than single hazards.”
CDHEs can begin with either a heatwave or a drought.
The sequence of these extremes is important, the study says, as they have different drivers and impacts.
For example, in a CDHE where the heatwave was the precursor, increased direct sunshine causes more moisture loss from soils and plants, leading to a drought.
Conversely, in an event where the drought was the precursor, the lack of soil moisture means that less of the sun’s energy goes into evaporation and more goes into warming the Earth’s surface. This produces favourable conditions for heatwaves.
The study shows that the majority of CDHEs globally start out as a drought.
In recent years, there has been increasing focus on these events due to the devastating impact they have on agriculture, ecosystems and public health.
In Russia in the summer of 2010, a compound drought-heatwave event – and the associated wildfires – caused the death of nearly 55,000 people, the study notes.
The record-breaking Pacific north-west “heat dome” in 2021 triggered extreme drought conditions that caused “significant declines” in wheat yields, as well as in barley, canola and fruit production in British Columbia and Alberta, Canada, says the study.
Increasing events
To assess how CDHEs are changing, the researchers use daily reanalysis data to identify droughts and heatwaves events. (Reanalysis data combines past observations with climate models to create a historical climate record.) Then, using an algorithm, they analyse how these events overlap in both time and space.
The study covers the period from 1980 to 2023 and the world’s land surface, excluding polar regions where CDHEs are rare.
The research finds that the area of land affected by CDHEs has “increased substantially” since the early 2000s.
Heatwave-led events have been the main contributor to this increase, the study says, with their spatial extent rising 110% between 1980-2001 and 2002-23, compared to a 59% increase for drought-led events.
The map below shows the global distribution of CDHEs over 1980-2023. The charts show the percentage of the land surface affected by a heatwave-led CDHE (red) or a drought-led CDHE (yellow) in a given year (left) and relative increase in each CDHE type (right).
The study finds that CDHEs have occurred most frequently in northern South America, the southern US, eastern Europe, central Africa and south Asia.
Threshold passed
The authors explain that the increase in heatwave-led CDHEs is related to rising global temperatures, but that this does not tell the whole story.
In the earlier 22-year period of 1980-2001, the study finds that the spatial extent of heatwave-led CDHEs rises by 1.6% per 1C of global temperature rise. For the more-recent period of 2022-23, this increases “nearly eightfold” to 13.1%.
The change suggests that the rapid increase in the heatwave-led CDHEs occurred after the global average temperature “surpasse[d] a certain temperature threshold”, the paper says.
This threshold is an absolute global average temperature of 14.3C, the authors estimate (based on an 11-year average), which the world passed around the year 2000.
Investigating the recent surge in heatwave-leading CDHEs further, the researchers find a “regime shift” in land-atmosphere dynamics “toward a persistently intensified state after the late 1990s”.
In other words, the way that drier soils drive higher surface temperatures, and vice versa, is becoming stronger, resulting in more heatwave-led compound events.
Daily data
The research has some advantages over other previous studies, Yeh says. For instance, the new work uses daily estimations of CDHEs, compared to monthly data used in past research. This is “important for capturing the detailed occurrence” of these events, says Yeh.
He adds that another advantage of their study is that it distinguishes the sequence of droughts and heatwaves, which allows them to “better understand the differences” in the characteristics of CDHEs.
Dr Meryem Tanarhte is a climate scientist at the University Hassan II in Morocco, and Dr Ruth Cerezo Mota is a climatologist and a researcher at the National Autonomous University of Mexico. Both scientists, who were not involved in the study, agree that the daily estimations give a clearer picture of how CDHEs are changing.
Cerezo-Mota adds that another major contribution of the study is its global focus. She tells Carbon Brief that in some regions, such as Mexico and Africa, there is a lack of studies on CDHEs:
“Not because the events do not occur, but perhaps because [these regions] do not have all the data or the expertise to do so.”
However, she notes that the reanalysis data used by the study does have limitations with how it represents rainfall in some parts of the world.
Compound impacts
The study notes that if CDHEs continue to intensify – particularly events where heatwaves are the precursors – they could drive declining crop productivity, increased wildfire frequency and severe public health crises.
These impacts could be “much more rapid and severe as global warming continues”, Yeh tells Carbon Brief.
Tanarhte notes that these events can be forecasted up to 10 days ahead in many regions. Furthermore, she says, the strongest impacts can be prevented “through preparedness and adaptation”, including through “water management for agriculture, heatwave mitigation measures and wildfire mitigation”.
The study recommends reassessing current risk management strategies for these compound events. It also suggests incorporating the sequences of drought and heatwaves into compound event analysis frameworks “to enhance climate risk management”.
Cerezo-Mota says that it is clear that the world needs to be prepared for the increased occurrence of these events. She tells Carbon Brief:
“These [risk assessments and strategies] need to be carried out at the local level to understand the complexities of each region.”
The post Heatwaves driving recent ‘surge’ in compound drought and heat extremes appeared first on Carbon Brief.
Heatwaves driving recent ‘surge’ in compound drought and heat extremes
Greenhouse Gases
DeBriefed 6 March 2026: Iran energy crisis | China climate plan | Bristol’s ‘pioneering’ wind turbine
Welcome to Carbon Brief’s DeBriefed.
An essential guide to the week’s key developments relating to climate change.
This week
Energy crisis
ENERGY SPIKE: US-Israeli attacks on Iran and subsequent counterattacks across the Middle East have sent energy prices “soaring”, according to Reuters. The newswire reported that the region “accounts for just under a third of global oil production and almost a fifth of gas”. The Guardian noted that shipping traffic through the strait of Hormuz, which normally ferries 20% of the world’s oil, “all but ground to a halt”. The Financial Times reported that attacks by Iran on Middle East energy facilities – notably in Qatar – triggered the “biggest rise in gas prices since Russia’s full-scale invasion of Ukraine”.
‘RISK’ AND ‘BENEFITS’: Bloomberg reported on increases in diesel prices in Europe and the US, speculating that rising fuel costs could be “a risk for president Donald Trump”. US gas producers are “poised to benefit from the big disruption in global supply”, according to CNBC. Indian government sources told the Economic Times that Russia is prepared to “fulfil India’s energy demands”. China Daily quoted experts who said “China’s energy security remains fundamentally unshaken”, thanks to “emergency stockpiles and a wide array of import channels”.
‘ESSENTIAL’ RENEWABLES: Energy analysts said governments should cut their fossil-fuel reliance by investing in renewables, “rather than just seeking non-Gulf oil and gas suppliers”, reported Climate Home News. This message was echoed by UK business secretary Peter Kyle, who said “doubling down on renewables” was “essential” amid “regional instability”, according to the Daily Telegraph.
China’s climate plan
PEAK COAL?: China has set out its next “five-year plan” at the annual “two sessions” meeting of the National People’s Congress, including its climate strategy out to 2030, according to the Hong Kong-based South China Morning Post. The plan called for China to cut its carbon emissions per unit of gross domestic product (GDP) by 17% from 2026 to 2030, which “may allow for continued increase in emissions given the rate of GDP growth”, reported Reuters. The newswire added that the plan also had targets to reach peak coal in the next five years and replace 30m tonnes per year of coal with renewables.
ACTIVE YET PRUDENT: Bloomberg described the new plan as “cautious”, stating that it “frustrat[es] hopes for tighter policy that would drive the nation to peak carbon emissions well before president Xi Jinping’s 2030 deadline”. Carbon Brief has just published an in-depth analysis of the plan. China Daily reported that the strategy “highlights measures to promote the climate targets of peaking carbon dioxide emissions before 2030”, which China said it would work towards “actively yet prudently”.
Around the world
- EU RULES: The European Commission has proposed new “made in Europe” rules to support domestic low-carbon industries, “against fierce competition from China”, reported Agence France-Presse. Carbon Brief examined what it means for climate efforts.
- RECORD HEAT: The US National Oceanic and Atmospheric Administration has said there is a 50-60% chance that the El Niño weather pattern could return this year, amplifying the effect of global warming and potentially driving temperatures to “record highs”, according to Euronews.
- FLAGSHIP FUND: The African Development Bank’s “flagship clean energy fund” plans to more than double its financing to $2.5bn for African renewables over the next two years, reported the Associated Press.
- NO WITHDRAWAL: Vanuatu has defied US efforts to force the Pacific-island nation to drop a UN draft resolution calling on the world to implement a landmark International Court of Justice (ICJ) ruling on climate, according to the Guardian.
98
The number of nations that submitted their national reports on tackling nature loss to the UN on time – just half of the 196 countries that are part of the UN biodiversity treaty – according to analysis by Carbon Brief.
Latest climate research
- Sea levels are already “much higher than assumed” in most assessments of the threat posed by sea-level rise, due to “inadequate” modelling assumptions | Nature
- Accelerating human-caused global warming could see the Paris Agreement’s 1.5C limit crossed before 2030 | Geophysical Research Letters covered by Carbon Brief
- Future “super El Niño events” could “significantly lower” solar power generation due to a reduction in solar irradiance in key regions, such as California and east China | Communications Earth & Environment
(For more, see Carbon Brief’s in-depth daily summaries of the top climate news stories on Monday, Tuesday, Wednesday, Thursday and Friday.)
Captured
UK greenhouse gas emissions in 2025 fell to 54% below 1990 levels, the baseline year for its legally binding climate goals, according to new Carbon Brief analysis. Over the same period, data from the World Bank shows that the UK’s economy has expanded by 95%, meaning that emissions have been decoupling from growth.
Spotlight
Bristol’s ‘pioneering’ community wind turbine
Following the recent launch of the UK government’s local power plan, Carbon Brief visits one of the country’s community-energy success stories.
The Lawrence Weston housing estate is set apart from the main city of Bristol, wedged between the tree-lined grounds of a stately home and a sprawl of warehouses and waste incinerators. It is one of the most deprived areas in the city.
Yet, just across the M5 motorway stands a structure that has brought the spoils of the energy transition directly to this historically forgotten estate – a 4.2 megawatt (MW) wind turbine.
The turbine is owned by local charity