World leaders will gather in Brazil this year for Cop30 – the first Amazonian policeman – it’s worth a quick reality check on how we collectively track global greenhouse gas emissions reductions.
Despite 30 years of UN climate summits, about half of the carbon dioxide accumulated in the atmosphere since the Industrial Revolution has been released since 1990. By the way, in 1990, the Intergovernmental Panel on Climate Change, the world's authority on the science of climate change, published its First Assessment Report confirming the threat of man-made global warming. As scientists around the world prepare the IPCC's Seventh Assessment Report, we do so knowing that our work is still overshadowed by politics. Despite all the good intentions of half-measures, the truth is that the world remains disastrously off track to limit dangerous climate change.
In the avalanche of technical reports published earlier KS30The World Meteorological Organization said CO2 concentrations reached a record high of 423.9 ppm in 2024, with the rate of increase increasing sharply from 2023 to 2024, the largest annual increase since modern measurements began in 1957. The latest data from the Global Carbon Project shows that 90% of the world's total CO2 emissions in 2024 came from burning fossil fuels, with the remaining 10% coming from land-use changes, including deforestation and wildfires.
While rising fossil CO emissions2 Emissions in 2024 were driven by increases in gas and oil production, which account for just over half of global emissions, while coal combustion reached a record level of 41%. Despite the global Cop28 stocktaking call for all countries to do their part in the “fossil fuel transition”, there are still plans to produce more than twice as much fossil fuel in 2030 as is consistent with limiting global warming to 1.5C, with continued gas production rationalized as a “transition fuel” with lower emissions intensity.
Instead of focusing on economic incentives to quickly transition away from fossil fuels, climate policy relies heavily on feel-good “nature-positive” solutions that focus on neutralizing carbon emissions by planting trees instead of reducing industrial emissions. While protecting, enhancing and restoring natural carbon sinks such as forests and wetlands are inherently good things, researchers have shown that there is not enough land available to achieve the global goal of net-zero emissions using only nature-based solutions.
To achieve a net zero commitment, about 1 billion hectares are needed—an area larger than the United States of America. By 2060, at an unprecedented pace, more than 40% of this land will need to be converted from existing uses such as food production to carbon capture projects.
And even if this regenerative utopia can be realized, we know that forests take time to mature and can burn, so they cannot be considered a quick or permanent solution for storing carbon, especially in a rapidly changing climate. As extreme heat and aridity grip much of the planet, those good intentions can literally go up in smoke.
Science tells us that about half of the total CO2 what is emitted each year remains in the atmosphere, while the rest is absorbed by the Earth's oceans and terrestrial ecosystems. As the planet warms, these natural carbon sinks become less efficient at absorbing CO2.2This means more carbon accumulates in the atmosphere, further exacerbating global warming. Shifting the burden of mitigation to the land sector simply relieves the fossil fuel industry of the need to reduce emissions in the near term.
Achieving net zero by 2050 requires carbon dioxide removal (CDR), which currently relies almost exclusively on land-based measures to absorb excess carbon from the atmosphere. Polluters can simply buy carbon credits to offset their emissions and continue business as usual. Meanwhile, the energy imbalance caused by the burning of fossil fuels continues to further destabilize the Earth's climate. Essentially, we are adding even more carbon debt to our planetary credit card, leaving future generations with unpayable obligations.
To limit the extent and duration of exceeding the Paris Agreement's temperature targets, the world will ultimately need to move well beyond the net zero offset effect and begin to reduce accumulated historical emissions to achieve “net negative emissions.”
According to the latest data from the Global Carbon Project, vegetation-based CDR currently absorbs the equivalent of about 5% of annual carbon dioxide emissions from fossil fuels, while technology-based CDR accounts for only about one millionth of the CO2 emitted from fossil fuels. More generous industry estimates put it at about 0.1% of total global emissions. At the risk of sounding heretical, the political misrepresentation of net zero is an insidious loophole that distracts from the scientific imperative to address the root cause of our planet's overheating—fossil fuels.
While this scientific reality should dominate discussions at Cop30, history tells us that bland incrementalism and political groveling will prevail. Vague statements about future ambitions will continue to delay the urgent need for concrete immediate action. Until our leaders have the courage to put a price on carbon to finally end the fossil fuel era, we will add more and more carbon to the atmosphere, worsening the physical catastrophe now unfolding around us.
The dilemma we face is simple: respond wholeheartedly to the scientific reality of our predicament or endure the consequences of this profound moral failure for centuries.
