Earth 2.0°C: How to Make Passing the 1.5°C Climate Change Threshold An Opportunity

Addressing the climate crisis will be difficult and demand focused attention and action. It is not a problem that will go away, and in fact a lot of new evidence shows that the world is heating and changing faster, weather-wise, than we expected just a few years ago. Many highly vulnerable populations and ecosystems already are facing the devastating impacts of climate change. While the COP28 meeting in Dubai late last year provided some glimmers of hope that the world’s countries can meaningfully respond to climate change, it is increasingly clear that the rise in global temperature will exceed the 1.5°C (2.7°F) threshold first defined as part of the 2015 Paris Climate Agreement. Currently the earth has experienced approximately 1.15°C of heating above the 19th century baseline and will likely pass the 1.5°C level globally in the mid-2030s. The window of opportunity to forestall this event is about to close, as significant barriers including lack of financing and institutional capacity, and to say nothing of poverty, consumption, and lack of societal trust.

While the challenges to address the climate crisis are great, several valuable opportunities to advance climate solutions lie well within our grasp. It is important that we collectively work to achieve the goals of what is called “climate resilient development,” and thereby simultaneously adapt to growing climate risks and incentivize opportunities to reduce greenhouse-gas emissions. Together, these two aims could tackle climate change while promoting economic advancement that is both sustainable and equitable. Equity is central to the process of transition. Whether it is industries and employees retooling for a green economy, or communities fearing loss of their neighborhood to flooding or climate gentrification, the evidence is overwhelming that the more equitable and engaged the decision-making process, the more likely the climate action will be successful.

Two other key areas of climate solutions are central to our everyday lives: the quality of life in our cities and towns, and enrichment of the natural world which surrounds and is infused within them. We are living in a profoundly urban century. Currently 56% of the world’s 8.1 billion live in urbanized areas, and almost all the global population growth expected in the next several decades will be in metropolitan areas. At the same time, these places drive approximately 70% of the world’s greenhouse-gas emissions and are where most economic activity takes place.

Through responsible and equitable planning, the urban (re)construction taking place now can integrate the latest climate solutions while also making our cities and towns better places to live and provide all with a higher quality of life. Fundamental to this achievement is protecting and more effectively using the services that nature provides human society. Nature-based solutions to climate change can’t address all our climate adaptation and mitigation challenges, but the data are strong that the more we can protect and enhance biodiversity and ecosystem function, the more benefits we can accrue in flood reduction, urban cooling, and air- and water-quality protection.

A key question is whether or not we can make such significant changes. Peering back into our own recent history, we find lots of stories of how we have done so. In a soon-to-be-published book, Cities and Environmental Change: From Crisis to Transformation, I document many examples of how seemingly overwhelming urban environmental crises were addressed through innovation. For example, by the mid-1950s air pollution had become a significant health and economic issue in the greater Los Angeles region. Within a decade transformative new air-pollution science, stakeholder coalitions, and governance institutions had been created and put into practice.

On a grand scale, the modernization of cities—while far from perfect—brought significant advances in drinking-water supply, sanitation, electrification, mass public transit, and recreation in many places. However, these developments were uneven, and today many cities, particularly in the Global South, are growing without the necessary infrastructure to adequately support the local population. Climate-resilient development is an opportunity to reduce or even eliminate these discrepancies.

The convergence of global climate change, rapid urbanization, and growing demands for economic and social equity create both an immediate imperative for action, and a rare opportunity to transform the present and create a better future. Successful solutions to past urban environmental crises can give us insights into how to best seize this opportunity: They show the importance of a flexible response where lived experiences, and the needs of multiple stakeholders are considered in policymaking.

Furthermore, we know that solutions should focus on securing the needed knowledge, financing, and decision-making capacity in advance, and being prepared to act when a window opens. Shocks like massive floods and disease outbreaks can become tipping points and bring attention to issues; but if emergent policies are to be effective and provide long-lasting solutions, they must also address underlying societal conditions, such as inequity and lack of trust in those in power due to a history of being cut out of the decision-making process.

Already, the world is full of small-scale climate-action success stories and other experiments that are making a difference. The historical evidence shows that to rapidly scale these up, we need to better monitor and evaluate these examples, bring in people and institutions from all levels of government, tap the incentive motives of the private sector, and address the concerns of those opposed to change. Even as the global community is failing the test of meeting the 1.5°C threshold, we have other resources to bring into the fight, and many of them are embedded in the history and culture of places and how we have addressed our past environmental crises.