According to most metrics, economic inequalities across the world have been declining since the late 1980s.
This has been driven by decreasing inequalities between countries – due to rapid economic growth in Asia – and has occurred despite increasing inequalities within a number of countries.
However, this trend could be reversed by the impacts of climate change.
While the repercussions of a warming climate are being felt in all corners of the world, the scale of these impacts on different countries, regions, communities and individuals varies hugely. The degree of economic inequality in the future will largely depend on how well different groups can adapt.
In a new review study, published in Environmental Research Letters, we analysed the existing literature and gathered evidence on whether, where and how climate change exacerbates economic inequality.
We find robust evidence that climate change impacts do indeed increase economic inequality and disproportionately affect the poor – both globally and within countries on all continents.
Climate change increases inequalities locally and globally
Our review covers 127 peer-reviewed studies into climate change and inequality.
These research papers cover a wide range of geographies, climate impacts, types of economic inequality measured (such as income disparities, differences in consumption or welfare disparities), methods used (such as econometric models or surveys) and findings.
The vast majority of studies confirm that climate change is exacerbating economic inequalities or hitting the poorest the hardest. This finding holds true across regions, types of physical impacts, sectors, types of inequalities and assessment methods. It is particularly prominent in studies that compare the impact of climate change across countries.
There are only two studies that find that climate change reduces inequality, but they focus on specific local circumstances – that is, flooding in Pakistan or price disparities among fishers and traders in Mexico.
Similarly, four papers find that the wealthy – whether households or countries – are more affected by climate change than the poor. However, these instances are exceptions and mostly limited to specific circumstances. For example, one study shows that the tropical cyclone Bulbul in Bangladesh caused higher losses for richer shrimp farmers, because they had larger farms.
The chart below summarises these overarching results across the 127 studies, categorised by the percentage of studies showing a negative (red), positive (blue) or mixed (yellow) impact on inequality. Orange indicates a finding that does not fit one of the categories, while grey shows studies that could not reach a conclusion.
The different bars represent the geographical focus of the different studies. Most of the studies we reviewed either look at the global picture (46) or focus on individual countries (44).
When it comes to global studies, the consensus is that climate change is widening inequalities or affecting the poor the most, with around 78% of the papers reaching this conclusion.
Some studies also highlight other groups being disproportionately impacted by climate change, such as rural communities, urban populations, women or specific regions and sectors.
However, there’s a minority of papers that remain inconclusive about both the impact of climate change on inequalities and which groups are most affected.
When it comes to national studies, the trend remains consistent: around 68% of these papers find that climate change is driving up economic inequality or hitting the poorest the hardest (30 out of 44 papers).
As the map below shows, this holds true in all parts of the world. The purple shading indicates the number of studies finding a negative climate impact on inequality for each country.
The countries with the highest number of studies (more than five) showing that climate change increases economic inequality or disproportionately affects the poor are China, Brazil, Ethiopia and the US.
Different climate impacts contribute to inequality
Looking at the breakdown of studies, we found that the percentage of papers pinpointing a particular climate impact as exacerbating inequality or affecting the poor more significantly ranges from 60% for changes in rainfall to 89% for sea level rise.
You can see this in the left-hand chart below, which shows the findings of the literature review separated by climate impact. The right-hand chart shows the findings separated by sector. The categories are the same as in the earlier chart.
A majority of studies focus on the impact of rising temperature, with 72% of these concluding that temperature changes worsen economic inequality or affect the poor the most.
Most of the studies that find a reduction in inequality concern extreme weather events. This is often because these studies assess the impact on physical assets, which are predominantly owned by the wealthiest.
There are several channels through which biophysical climate change impacts translate into economic effects. These channels include broad economic effects that influence all sectors, changes in agricultural revenues due to factors such as crop yield declines, impacts on labour productivity, changes to infrastructure and physical assets, shifts in energy demand or water availability.
We found that studies identifying labour productivity or energy as the main channel through which climate change affects economic inequalities overwhelmingly conclude that inequalities increase or that the poor are more impacted.
A decline in labour productivity may indeed increase inequality if it disproportionately affects low-skilled workers, especially those who work outdoors or in non-air-conditioned environments.
Notably, a large proportion of the studies where physical assets are identified as the main channel suggest that inequality actually decreases due to climate change or that the wealthy suffer more. This is because rich individuals tend to face greater losses due to the higher value of their property.
Tackling climate impacts on inequality
Our investigation into the impacts of climate change on economic inequality was motivated by the need to better understand the climate change impacts are distributed across the world. This provides the other side of the coin to the effects of mitigation policies on inequality, which are often more widely discussed.
The evidence strongly indicates that the impacts of a warming climate are regressive across countries. Tackling the impacts of climate change on economic inequality will demand substantial policy changes and financial resources.
At the national level, policymakers will need to ensure that adaptation finance and loss and damage compensation effectively reach low-income households to reduce their vulnerability and increase their resilience to climate change impacts.
The results of our review underscore the importance of policymakers integrating climate risk management strategies into the design of “climate-proof” social programmes in poor regions, which are crucial for achieving climate justice objectives.
Of course, other forms of inequality beyond economic inequality, such as gender inequality, are important and interact with climate change, but this is a topic for another review.
The post Guest post: How climate change could reverse gains in global inequality appeared first on Carbon Brief.
Guest post: How climate change could reverse gains in global inequality
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