It’s been a record-setting year.
Between last year’s United Nations Climate Change Conference and the one starting later this week, climate change has hit particularly hard. It has stoked raging wildfires in Canada, a record-breaking hurricane in Mexico, drought
and flooding in Africa, deadly heat waves in India, Europe and the United States, and so much more. The last 12 months have been the planet’s hottest in recorded history, and the latest climate report from the UN warns that nations are on a path to overheat the Earth well above the limits enshrined by the 2015 Paris climate agreement.
But underlying all the destruction is an important source of hope: none of the headlines tying these disasters to climate change would have been possible without dramatic advances in the relatively young field known as attribution science, which provides an evidentiary basis for linking human activity to climate change impacts. As COP28 kicks off, it’s essential to keep in mind the role of attribution science as a tool not only to show why we need to shut down climate pollution, but also to identify the unequal effects of global heating, and catalyze efforts to address them. To focus our efforts on the most impacted—a central subject this year, thanks to the recent agreement to create a “loss and damage fund” for the most vulnerable countries—we need to close the attribution data gaps between developed and developing worlds.
Attribution science relies on meticulously constructing an imaginary world where humans never polluted the atmosphere by burning coal, gas and oil. Scientists then compare that cooler alternative universe to our actual one, in which human activity has overheated the planet, and ask to what extent different weather events were more likely to occur because of the increase in global average temperatures. The first attempt to link climate change to extreme weather was a 2004 report examining a European heat wave the summer before.
Since then, scientists have honed their methods and pursued hundreds more studies. World Weather Attribution, an international collaborative co-founded in 2014 by scientists at Climate Central, Oxford University, the Red Cross/Red Crescent Climate Centre and others, pioneered the practice of attributing certain extreme events to climate change within days, instead of the usual academic cycle of months to years. Scientists have also expanded attribution to cover more climate impacts over time, such as sea level rise and related economic losses, or even to implicate a particular polluter, whether a country or a company. In one example, a Dutch court ordered Shell to reduce greenhouse gas emissions 45 percent by 2030, relying on source attribution in the decision.
Last year, a new advance in attribution, pioneered by Climate Central, allowed scientists to make attributions in real time—and even in the forecast. The Climate Shift Index makes climate change personal and specific instead of global, distant and abstract. Anyone, anywhere in the world, can log on and see how much more likely—or less likely—the day’s local temperatures are, because of human-driven climate change. Earlier this month, Climate Central used those daily assessments to tabulate climate fingerprints in 921 cities and 175 countries across these last 12 record-hottest months.
The growing awareness of how our actions create climate change, and how climate change creates destructive and deadly weather, have catalyzed not just news coverage but also data-driven policy changes and legal challenges around the world, from the local to the international level. Attribution science can inform new, more resilient policies such as land management strategies, emissions caps, urban planning, or renewable energy investment. For example, the first grants from the Federal Emergency Management Agency under the Inflation Reduction Act went to states affected by Hurricane Ida to pursue flood mitigation via a program that expressly links flooding impacts to climate change. Attribution science can also help build the case for global agreements of the kind that arise from gatherings like COP28.
To ensure that attribution science helps humanity as much as possible, and especially our most vulnerable populations, it’s essential that we close what’s called the “attribution gap.” As in so many fields of science and data analysis, attribution studies have a bias toward analyzing events in the wealthier, whiter and more developed parts of the world. One AI-powered report showed that climate change studies are twice as likely to focus on wealthier countries, which have more of the researchers, weather measurement infrastructure, computational capacity, and other resources beneficial for this work. And while efforts like the Climate Shift Index, with its everyday, worldwide coverage, go far in providing insights more equitably—and showing how less developed nations are indeed more affected—gaps persist. Without more data and attribution analysis in the developing world, efforts like the loss and damage fund will have more difficulty linking certain impacts to climate change, making it harder to show countries that have contributed least to climate pollution suffer disproportionate effects.
Beyond closing the data gap, attribution science needs to make itself widely accessible and easily communicated so that local journalists, communities and grassroots groups can use it in their work. Climate change is not the only human-related factor that may contribute to harm when extreme weather strikes. A complete perspective must ask probing questions about why communities are “vulnerable” in the first place—what economic, racial or other roots underlie that hastily built housing, the neighborhoods with no shade trees, the development in flood-prone areas? Without grassroots access to and use of attribution analyses—which sometimes find that climate change played little or no role in a weather disaster—political leaders may throw up their hands and just blame the bogeyman of warming, rather than being held accountable by the public for local laws and practices.
When climate science includes an equity lens, the results are powerful. Earlier this month, the U.S. released a climate assessment, the fifth study of its kind and the first to focus on inequalities in climate change impacts. It found that communities of color are less likely to have access to flood safety infrastructure, suitable housing, green space and other key elements of climate change adaptation—largely because of a history of racial discrimination, particularly in housing. It also notes that Indigenous communities are facing impacts that defy quantifying—the loss, to extreme weather, of cultural practices, burial sites and religious worship.
Indeed, it’s impossible to measure everything we might lose to climate change. But we can make sure to observe, record, analyze and publicize everything that we can—and then act on it.
Wendy Schmidt is co-founder and president of the Schmidt Family Foundation and Schmidt Ocean Institute. She is a founding board member of Climate Central. Dr. Benjamin Strauss is president, CEO and chief scientist of Climate Central.