Scientists Can Now Trace the Damage a Single Coal Mine or Gas Project Will Cause

Scientists have built an open-source tool that estimates how much a single fossil fuel project will warm the planet — and what that warming will cost people and nature.

The Carbon Impacts Tracer connects three things that were previously hard to link: the emissions a project is documented to produce, the additional warming those emissions cause, and the measurable damage that follows.

Governments have continued to approve new coal, oil and gas developments even as climate change worsens. Backers have often relied on what amounts to a "drop in the ocean" defence: a new project will add carbon dioxide, they concede, but the amount is small next to global emissions, and the harm from any one project cannot be isolated from the rest.

That argument is becoming harder to sustain. Attribution science — the field that identifies the role of climate change in specific disasters and extreme weather — has advanced quickly in recent years. The new tool extends the same approach to individual projects.

How the calculation works

The underlying physics is well established. The relationship between cumulative carbon dioxide emissions and global temperature rise is close to linear. For every trillion tonnes of CO₂ released into the atmosphere, the world warms by about 0.45°C, according to the latest assessment report of the Intergovernmental Panel on Climate Change. As of 2019, cumulative global emissions stood at about 2.4 trillion tonnes.

The tool applies this relationship to a project's publicly documented emissions, then estimates the consequences across eight categories. These include the number of people worldwide exposed to dangerous heat, glacier melt, and heatwave deaths in Europe.

The researchers behind the tool say they include only those published studies robust enough to quantify the link between higher temperatures and a particular type of harm. That evidence threshold is why the list currently stops at eight categories. More will be added as the science strengthens. The link between European heatwave deaths and climate change, for example, is well established and reproducible; comparable research for Australia and other regions does not yet meet the criteria.

What the tool shows

Last year, experts from six universities in Australia and the United Kingdom published an assessment of the damage tied to emissions from the recently approved Scarborough gas project in Western Australia. Three of this article's authors were involved in that research.

They found that 876 million tonnes of CO₂ from Scarborough would expose an additional 516,000 people worldwide to unprecedented heat, cause 484 heat-related deaths in Europe by 2100, and destroy millions more coral colonies during every future mass bleaching event on the Great Barrier Reef.

The new tool allows the same methodology to be applied to any fossil fuel project. It covers five proposed Australian projects and one in the United Kingdom. Woodside's proposed Browse to North West Shelf gas development, for instance, would emit 1,597 megatonnes of CO₂ over its lifetime, warming the planet by 0.00072°C — a figure the tool translates into almost 200,000 more people facing dangerous heat.

The findings matter beyond any single project. Under the Paris Agreement, countries have committed to holding global warming well below 2°C while pursuing efforts to limit it to 1.5°C. Every approved project adds to the cumulative total that determines whether those goals remain within reach.

What it does not do

The tool does not capture every consequence of a project, and its authors are explicit about that limitation. It measures only those harms for which scientific evidence is strong enough to support quantification, and it relies on emissions figures that companies and regulators make public.

What it does is assemble existing findings into a single chain: emissions to warming, and warming to damage. That chain gives regulators, courts and communities a way to weigh the specific effects of a project, rather than treating each one as negligible on its own.

Whether it changes approval decisions remains to be seen. But the "drop in the ocean" defence now has a measurable answer.