What does three degrees of global warming look like? | The Economist
- Global warming is currently at 1.1–1.3°C above pre-industrial levels; three degrees of warming would result in catastrophic outcomes including heat waves, droughts, extreme precipitation, and fires.
- Children born today are up to seven times more likely to face extreme weather conditions than their grandparents.
- Climate models indicate at least a one-in-four chance of reaching a three-degree scenario by the end of the century under current policies.
- Even under optimistic scenarios where all policy promises and net-zero targets are met, there remains a one-in-twenty chance of exceeding three degrees of warming.
- The United Nations and hundreds of scientists utilize state-of-the-art modeling to project these climate trajectories.
- Over 400,000 climate migrants arrived in Bangladesh annually, driven by rivers swollen by heavier rain and melting Himalayan glaciers washing away homes.
- Approximately 600 million smallholder farmers worldwide, who manage farms under two hectares, produce roughly one-third of the global food supply and are disproportionately vulnerable.
- In Central America's Dry Corridor, severe droughts are now four times more likely than in the last century, and annual rainfall could drop by up to 14 percent in a three-degree world.
- Nearly two-thirds of smallholders in Central America's Dry Corridor currently live in poverty, leading to child malnutrition and increased migration to the United States, which has quadrupled since 1990.
- A three-degree world could leave over a quarter of the global population enduring extreme droughts for at least one month annually, with Northern Africa potentially facing multi-year droughts.
- Ten percent of the global population resides on coastlines less than 10 meters above sea level; by 2100, sea levels could rise by half a meter from 2005 levels.
- In vulnerable low-lying cities like Lagos, up to one-third of the population could be displaced by rising seas, while villages in Fiji face total erosion without immediate seawall construction.
- Countries such as the Philippines and Myanmar will experience increased storm surges, further displacing populations into urban slums.
- If global warming reaches three degrees, many cities in Europe and North America (e.g., Paris, Berlin, New York) will face extreme heat waves and desolate conditions from storm surges.
- Cities act as amplifiers for climate events due to higher densities and the urban heat island effect, making unprepared urban centers particularly deadly.
- Dangerous "wet bulb" temperatures, where human sweat cannot evaporate and the body overheats, have a survival limit of 35°C; regions including parts of the US, Mexico, Pakistan, and the Persian Gulf could reach this threshold by 2100.
- In a three-degree scenario, tens of millions of people annually could be displaced by climate disasters, straining urban infrastructure and existing migration patterns.
- Climate displacement could exacerbate geopolitical tensions over water resources, specifically in contested regions involving China, India, Pakistan, Turkey, and Iraq.
- While adaptation strategies like sea walls, air conditioning, and agricultural diversification can reduce suffering, they cannot eliminate it in a three-degree world.
- Greenhouse gas emissions are projected to rise by 16% from 2010 levels by 2030 despite existing pledges, making the three-degree scenario uncomfortably likely.
- Experts state that avoiding a three-degree future requires urgent mitigation efforts and the pursuit of negative emissions to lower temperatures after they peak.