While the primary focus of tackling climate change is on carbon dioxide (CO2), a group of other greenhouse gases and aerosols – known as “super pollutants” – is having a profound impact on both global temperature and human health.
They are responsible for around 45% of global warming to date, as well as millions of premature deaths each year.
Cutting emissions of these non-CO2 pollutants, which include methane, hydrofluorocarbons and black carbon, is seen as one of the quickest ways to tackle climate change.
Studies have shown how global action to reduce emissions of super pollutants could avoid four times more warming by 2050 than decarbonisation policies alone.
At the same time, it could prevent some 2.4 million deaths a year caused by air pollution.
And, yet, emissions of many super pollutants are soaring.
In this article, we unpack what super pollutants are and why they have an outsized impact on the climate and public health.
The other 45%
CO2 is responsible for around 55% of global warming to date. The other 45% comes from super pollutants: methane; black carbon; fluorinated gases; nitrous oxide; and tropospheric ozone.
These pollutants are present at lower concentrations in the atmosphere than CO2. But each tonne of these substances has a more powerful warming impact than a tonne of CO2 – up to tens of thousands of times more. As a result, they are still responsible for a lot of warming.
Most super pollutants remain in the atmosphere for less time than CO2, ranging from a few days to a few decades. These are known collectively as “short-lived climate pollutants”.
Others, including nitrous oxide and some fluorinated gases, can have very long lifetimes – even tens of thousands of years in some cases.
As well as being substantial contributors to global warming, super pollutants are a major threat to human health.
Poor air quality caused by these pollutants has been linked to a series of heart and respiratory diseases, as well as lung cancer and strokes.
Methane, black carbon and tropospheric ozone are the super pollutants with the most significant impacts on health.

Methane
Methane is the second-largest contributor to climate change after CO2. In its first 20 years in the atmosphere, when it is most potent, methane has a warming potential more than 80 times greater than CO2.
Methane has both human-related and natural sources. Global human-caused methane emissions come from three main areas:
- Agriculture (~40%), such as from livestock and rice production.
- Fossil fuels (~35%), as a by-product of fossil fuel extraction, storage and distribution.
- Waste (~20%), from food and other organic materials decaying in landfills and wastewater.
Recent research has shown that methane emissions have continued to rise, with “no hint of a decline”. According to the World Meteorological Organization, atmospheric concentrations of methane in 2023 were 265% higher than pre-industrial levels.
Methane impacts public health indirectly in a number of ways.
By increasing atmospheric temperatures, disrupting rainfall patterns and contributing to the formation of tropospheric ozone, emissions of the gas contribute to crop failures which exacerbate food insecurity. The gas has been estimated to cause up to 12% of annual agricultural losses of staple crops.
Increased food insecurity has a number of implications for human health. Research has indicated that nearly half of deaths among children under five are linked to undernutrition. These mostly occur in low- and middle-income countries.
However, the biggest impact methane has on health is its contribution to the creation of tropospheric ozone.
Tropospheric ozone
Tropospheric ozone is among the shortest-lived super pollutants, with an atmospheric lifetime of just days to weeks.
But, despite its short-lived nature, the greenhouse gas has a major impact on human health. It has been linked to around 600,000 to 1 million premature respiratory deaths annually and a similar number of premature cardiovascular deaths.
The greenhouse gas does not have any direct sources, but is formed when hydrocarbons – including methane, volatile organic compounds (VOCs) and carbon monoxide – react with nitrogen oxides in the presence of sunlight.
Concentrations of this harmful pollutant are rising. Soaring emissions of its precursor gas – methane – are believed to be responsible for up to half of the observed increase.
As a major component of smog, tropospheric ozone can worsen bronchitis and emphysema, trigger asthma and permanently damage lung tissue. Children, the elderly and people with lung or cardiovascular diseases are particularly at risk from ozone exposure.
In addition to harming human health, studies have shown that many species of plants are sensitive to ozone, including agricultural crops, grassland and trees. Tropospheric ozone damages plants in many ways, including by entering pores in their leaves and burning plant tissue during respiration.
As a result, ozone emissions are a growing threat to food security.
Black carbon
Black carbon is formed by the incomplete combustion of wood, biofuels and fossil fuels in a process which also creates carbon dioxide, carbon monoxide and VOCs.
Commonly known as soot, black carbon has a warming impact up to 1,500 times stronger than CO2 per tonne. The pollutant dims sunlight that reaches the Earth, interferes with rainfall patterns and disrupts monsoons. Where it settles on snow and ice, it reduces reflectivity and increases melt rates.
Black carbon is a major component of fine particulate matter air pollution (PM2.5), which has been linked to a raft of negative health outcomes, including premature death in adults with heart and lung disease, strokes, heart attacks, chronic respiratory diseases such as bronchitis, aggravated asthma and other cardio-respiratory symptoms.
Each year, around 4–8 million deaths globally are associated with long-term exposure to PM2.5.
While untangling how many deaths are directly attributable to black carbon is tricky, there is growing evidence of its specific health impacts.
Studies have shown that exposure to black carbon correlates with high blood-pressure levels more strongly than PM2.5 overall. Exposure to the pollutant in pregnancy has also been found to impact the development and health of newborn children and is associated with reduced birthweight.
An integrated approach to climate and health
There has been growing political momentum around the threat of super pollutants.
One clear example of this is the Global Methane Pledge, an initiative launched at the COP26 climate summit in Glasgow in 2021. The pledge, which has been backed by 158 countries and the European Union, commits governments to collectively reduce global human-caused methane emissions by at least 30% below 2020 levels by 2030.
However, methane emissions are going in the wrong direction. Emissions are currently on track to increase by 5-13% above 2020 levels by 2030, according to a 2022 analysis from the Climate and Clean Air Coalition and United Nations Environment Programme.
Building awareness of the health consequences of climate change can encourage policymakers to set ambitious limits on super pollutant emissions. It can also underline the importance of a joined-up policy approach to climate and health, where emissions reduction pledges can help spur policies that improve lives.
The Global Methane Pledge and the Kigali Amendment – an international agreement to reduce the production and use of hydrofluorocarbons – are just two pledges that could have immediate and dramatic effects on public health, if fully implemented.
Cutting emissions of super pollutants is one of the most effective ways to “keep 1.5C alive” in the near-term, while protecting health and avoiding tipping points that could cause irreversible shifts in the Earth system.
Combined with the health benefits, rapidly reducing emissions of these pollutants is a clear win-win for people and the planet.
The post Guest post: How ‘super pollutants’ harm human health and worsen climate change appeared first on Carbon Brief.
Guest post: How ‘super pollutants’ harm human health and worsen climate change
Climate Change
From Ownership to Relationship: Reclaiming Our Responsibilities to Land
Humans are deeply responsible for the current climate crisis, and a significant root cause is the nationstate fiction that land and morethanhuman relations can be reduced to “property” to be owned, controlled, and exhausted for profit. This ownership paradigm is inseparable from the Doctrine of Discovery and Terra Nullius, by Church and Crown, which gave moral and legal cover to seize Indigenous lands and suppress Indigenous laws of responsibility and reciprocity with the web of life.
The modern idea that a Crown or state holds “underlying title” to Indigenous lands in Canada flows directly from these doctrines, which treated alreadyinhabited territories as “empty” and available to Christian European empires. In practice, this has allowed Canada to assert ultimate authority over unceded territories, reduce Indigenous Nations to “claimants” on their own lands, and legitimize largescale extraction and dispossession.
This way of thinking has fractured the integrity of land and the broader web of life. When land is seen as property rather than as a living relation, decisions are framed around shortterm economic gain instead of the continuity of waters, soils, plants, animals, and communities. From clearcut logging and fossil fuel expansion to exclusionary conservation, the same logic of unilateral control has fragmented habitats, undermined biodiversity, and disrupted longstanding Indigenous stewardship practices.
For Indigenous Nations, climate change intensifies these harms. Shifting seasons, altered animal migrations, and degraded waters are eroding the conditions for hunting, fishing, trapping, and gathering, and with them, language, ceremony, and landbased teachings. This is not just environmental damage; it is an attack on living Indigenous legal orders that were designed to keep human behaviour accountable to the land.
Politically, the ownership myth entrenches a hierarchy in which the state imagines itself as the final decisionmaker over territories it claims. Indigenous Nations are pushed into endless “consultation,” while absolute authority and benefitsharing rarely shift. Economically, this worldview feeds a growthdriven model in which “wealth” is measured by what can be extracted, privatized, and traded, rather than by the health of ecosystems and communities. Socially and spiritually, it normalizes disconnection from place, where many people experience land as a commodity rather than as a living network to which they belong and are accountable.
Human arrogance thrives in this disconnection. The belief that humans stand above other beings, entitled to engineer, commodify, or sacrifice them for convenience and profit, has opened a climate change Pandora’s box: land turned into property, relations turned into resources, and the garden of life left to rot around us while humanity chooses profits over peace. Our current geopolitical and geoeconomic crises are symptoms of the same disorder, power and control elevated above responsibility and reciprocity.
There is no doubt that human activities, shaped by colonialism, fossil capitalism, and the property mindset, are driving the climate crisis. Yet Indigenous knowledge holders and communities across Turtle Island insist that genuine solutions must be rooted in decolonization, land back, and the restoration of landbased responsibilities and Indigenous selfdetermination. Indigenousled renewable energy projects, landback agreements, and the revitalization of traditional land use practices show it is possible to align livelihoods with the wellbeing of ecosystems instead of their destruction.
This moment demands more than new policies; it calls for a profound shift in worldview. Humans are not owners, but relatives, not masters, but participants in a living treaty with the rest of creation. Moving from ownership to relationship feeling as well as thinking our way back into reciprocity offers one path out of the current crisis.
Householdlevel conversations are an essential place to begin reconciling with Mother Earth. These conversations can ask different questions: Who rather than What is this land to us? What are our responsibilities here? How do our everyday choices, food, energy, transport, investments, and political action support or undermine Indigenousled visions of climate justice? When families and communities begin to live as if land is a relative rather than a possession, the foundations of a different future begin to take root.
Blog by Rye Karonhiowanen Barberstock
Image Credit: Davey Gravy, Unsplash
The post From Ownership to Relationship: Reclaiming Our Responsibilities to Land appeared first on Indigenous Climate Hub.
From Ownership to Relationship: Reclaiming Our Responsibilities to Land
Climate Change
Human Foolishness in Floodplains
Across the planet, human settlements have been built as if rivers, oceans, and forests were mere backdrops to human stories rather than powerful forces with their own laws and rhythms. Building in flood zones and reshaping rivers for convenience are among the clearest examples of this folly. The land has been forced to serve human needs, instead of humans learning to live within the land’s limits and patterns.
Floodplains are not “vacant land.”
Floodplains exist because rivers regularly rise, spread, and deposit sediment, renewing soils and supporting rich ecosystems. When development paves, drains, and walls off these areas, two things happen at once: the land loses its capacity to absorb and slow water, and the people who move in inherit predictable risk. Subdivisions, highways, and industrial sites on floodplains in British Columbia and elsewhere have repeatedly suffered catastrophic damage during extreme rainfall and snowmelt, drowning farmlands, homes, and critical infrastructure.
Each socalled “natural disaster” becomes an expensive lesson paid in insurance claims, disaster assistance, and rebuilding costs, even though the river did what floodplains are meant to do: spread, move, and reclaim space. When homes and farms in interior B.C. flood, or when subway tunnels in Toronto fill with water during intense storms, it is not simply climate change striking at random; it is climate change colliding with decades of landuse decisions that pretended water had no right of way.
Dams and the broken lives of rivers
Dams are often framed as engineering triumphs, providing flood control, hydropower, and water storage. Yet every dam interrupts a river’s life systems: sediment transport, fish migration, nutrient flows, and seasonal flooding of wetlands and floodplains. Large dams have submerged valleys and Indigenous homelands, altered fish populations, and changed downstream flow regimes, undermining food security and cultural practices.
Their economic “benefits” frequently ignore these losses, as well as the costs of maintenance, aging infrastructure, and climatedriven changes in flows that can reduce power generation and increase safety risks. When dams fail or when extreme events exceed their design standards, the damage can be enormous: lives lost, communities evacuated, ecosystems damaged, and public funds poured into emergency response and repair. Each failure is a reminder that rivers have their own energies and attempts to control them permanently will always carry risk.
The planet is already saying “no.”
The future of infrastructure is being negotiated now, not only in boardrooms and design studios, but also in floodwaters, wildfires, coastal erosion, and heat waves. Coastal erosion and storm surge are claiming homes built too close to retreating shorelines, with houses collapsing into the sea in Atlantic Canada and other coastal regions. Increased wildfire frequency and intensity have led to devastating townlevel burns in communities like Lytton, B.C., and Jasper, AB, revealing how forestinterface development and fire suppression have amplified risk.
Urban flooding in cities like Toronto, where underpasses and transit systems are routinely overwhelmed, shows that stormwater systems designed for a gentler climate are no match for today’s extremes. In all of these cases, the planet is effectively setting new terms: specific forms of development, placement, and density are no longer viable. Engineering can delay consequences, but cannot cancel the underlying reality that water, fire, and wind will seek their own paths.
Responsive and adaptive infrastructure
The built environment of the future must move away from bruteforce control toward responsive, adaptive relationships with natural systems. Key shifts include:
Building with, not against, landforms
- Avoiding new development in highrisk floodplains, steep fireprone slopes, eroding coasts, and other hazard zones, while prioritizing retreat, relocation, and restoration.
- Using green infrastructure such as wetlands, permeable surfaces, and urban forests to absorb water, reduce heat, and buffer storms instead of relying solely on concrete and pipes.
Allowing rivers and coasts to move
- Restoring floodplains and riparian zones so rivers can expand safely during high flows, reducing downstream damage.
- Reconsidering and, where possible, removing or reoperating dams to restore ecological function while meeting human needs in less damaging ways.
Designing for failure and change
- Accepting that some infrastructure will be overtopped, burned, or inundated, and designing systems that fail safely with clear recovery pathways.
- Regularly updating risk assessments and landuse plans as climate patterns shift, rather than assuming static baselines.
These approaches require money, time, and political will, but rebuilding in the same vulnerable places again and again also carries immense financial and human costs.
Honouring land instead of abusing it
At the heart of this shift is a change in how land is understood:
- Not as an object of ownership and control, but as a place with its own history, rights, and patterns to be respected.
- Not as a blank slate for any project, but as a living system that will answer attempts at domination with erosion, flooding, fire, and instability.
For Indigenous Nations, this perspective is not new. Land, rivers, and other beings are understood as relatives with agency, not passive surfaces. Planning and building within this framework means asking whether a place can safely host a particular kind of development, not just whether it is technically feasible, and designing structures and communities that can adapt as conditions change instead of locking in rigid forms that will become liabilities.
A call to new generations
This is a moment for younger generations of planners, engineers, architects, and community leaders to refuse the old arrogance that assumed the land would adapt to human projects. The new work is to create infrastructure and communities that adapt to evolving land and climate realities. That means learning to read landscapes, waters, and fire histories as carefully as any technical manual; challenging developments that place people and ecosystems in predictable harm’s way; and innovating in ways that honour place, minimize disruption, and embrace reversible, flexible, ecologically grounded design.
The foolishness of building in flood zones and of damming rivers without regard for human life has been exposed by climate change. The question now is whether humanity will continue to abuse land as if it were inert or finally treat it with the dignity it has always deserved, recognizing that the planet will always have the final word.
Blog by Rye Karonhiowanen Barberstock
Image Credit: Ries Bosch, Unsplash
The post Human Foolishness in Floodplains appeared first on Indigenous Climate Hub.
Climate Change
The Fight Over Logging on U.S. Public Lands Isn’t Done Yet
Despite an Oregon court ruling in January invalidating a rule that enabled clear cutting, it’s far from the last salvo in the battle for how to fight fires or manage forests—and who can profit from it.
From our collaborating partner Living on Earth, public radio’s environmental news magazine, an interview by host Steve Curwood with Timothy Ingalsbee, executive director of Firefighters United for Safety, Ethics and Ecology.
-
Greenhouse Gases7 months ago
Guest post: Why China is still building new coal – and when it might stop
-
Climate Change7 months ago
Guest post: Why China is still building new coal – and when it might stop
-
Greenhouse Gases2 years ago嘉宾来稿:满足中国增长的用电需求 光伏加储能“比新建煤电更实惠”
-
Climate Change2 years ago
Bill Discounting Climate Change in Florida’s Energy Policy Awaits DeSantis’ Approval
-
Climate Change2 years ago
Spanish-language misinformation on renewable energy spreads online, report shows
-
Climate Change2 years ago嘉宾来稿:满足中国增长的用电需求 光伏加储能“比新建煤电更实惠”
-
Climate Change Videos2 years ago
The toxic gas flares fuelling Nigeria’s climate change – BBC News
-
Carbon Footprint2 years agoUS SEC’s Climate Disclosure Rules Spur Renewed Interest in Carbon Credits




