Table of Contents
- Understanding Climate Sensitivity Models: Why Global Temperatures May Rise Faster Than Predicted
- Recommendation
- Take-Aways
- Summary
- Global temperatures could rise twice as quickly as predicted.
- Scientists are arguing about “climate sensitivity,” a crucial metric in predictive models.
- Prepare for the worst, taking targeted actions to reduce emissions and the effects of climate change.
- About the Speaker
Understanding Climate Sensitivity Models: Why Global Temperatures May Rise Faster Than Predicted
Discover why climate sensitivity is the most debated metric in climate science and how new models suggest global warming could accelerate faster than expected. Learn from physicist Sabine Hossenfelder’s expert analysis on what these findings mean for the future and actionable steps we can take to address climate change now.
Ready to uncover the truth behind climate sensitivity and what it means for our planet’s future? Keep reading to explore Sabine Hossenfelder’s insights, understand the science behind the headlines, and learn practical strategies to help combat climate change before it’s too late.
Recommendation
What if the models most climate scientists are using to make predictions are wrong and global temperatures are actually rising much more quickly than expected? Physicist Sabine Hossenfelder explains why confusion about one metric, climate sensitivity, is creating two dueling timelines regarding climate change. Humanity would be wise to consider the possibility, warns Hossenfelder, that there’s less time to offset the impacts of climate change than previously imagined, and to respond accordingly.
Take-Aways
- Global temperatures could rise twice as quickly as predicted.
- Scientists are arguing about “climate sensitivity,” a crucial metric in predictive models.
- Prepare for the worst, taking targeted actions to reduce emissions and the effects of climate change.
Summary
Global temperatures could rise twice as quickly as predicted.
2023 went down in history as having the hottest recorded temperatures since the mid-19th century. That same year, antarctic sea ice also hit a record low, while people around the world experienced longer and hotter heat waves than in previous years. But far from being an outlier, it’s possible this is a harbinger of what’s to come as climate change’s effects rapidly accelerate.
“I feel like I need to tell you about this because the lives of hundreds of millions of people depend on it.” (Sabine Hossenfelder)
Scientists are struggling to agree on one crucial number: equilibrium climate sensitivity (ECS), or just climate sensitivity for short. Climate sensitivity is a metric used to generate prediction models of how fast global temperatures will rise if carbon dioxide (CO2) levels continue rising at their current rate. Until 2019, climate models — collected in a World Climate Research Program project called the Coupled Model Intercomparison Project (CMIP) — set climate sensitivity at between 2°C and 4.5°C, but in 2019’s model assessment, climate sensitivity increased to 5°C. Translation: The climate situation could rapidly deteriorate, and things would “go to hell twice as fast as we expected.”
Scientists are arguing about “climate sensitivity,” a crucial metric in predictive models.
If you’re wondering why you haven’t heard that climate change predictions became much more dire in 2019, it’s because many climate scientists dismissed these models, deciding that they must be failing. Because 10 out of 55 of the new models had an ECS of more than five, which didn’t align with past models, scientists began referring to what they believed to be an error as the “hot models problem.”
“That the climate sensitivity might be considerably higher than most current policies assume is a big problem.” (Sabine Hossenfelder)
However, these hot models shouldn’t be dismissed so quickly. In particular, one hot model from the UK Met Office, the government weather and climate agency, is predicting the weather with more accuracy than other models, so it appears possible that the model with the higher ECS is actually accurate. However, if this number is correct, humanity may see dire consequences, which include the collapse of world economies in 20 years; the rapid decline of crop yields near the equator; drought and famine in the world’s poorest countries; new pandemics; and the mass migration of hundreds of millions of people, displaced by climate change, triggering geopolitical tensions.
Prepare for the worst, taking targeted actions to reduce emissions and the effects of climate change.
If living becomes an act of survival on an increasingly uninhabitable planet, humanity could enter an “age of regress” instead of progress — because who can work when they’re focusing on surviving? If the ECS numbers are right, the Earth’s population could even shrink by several billion people. Those who think AI will solve the problem, should think again: Humanity is not missing technological solutions, but rather, it’s failing to implement those it already has.
“I don’t know who’s right or wrong, but for me, the bottom line is that the possibility of a high climate sensitivity below 5°C can’t be easily dismissed.” (Sabine Hossenfelder)
Some climate scientists, such as James Hansen, have published research that supports findings posed by these hot models, while critics call his predictions a subjective and unjustified “worst-case scenario” — it’s ultimately unclear which models are right or wrong. If you’re wondering what to do when grappling with this uncertainty, consider the following recommendations: Create a carbon-dioxide emissions price; build nuclear; and offset emissions with carbon removal. Also, focus on restoring wildlife and nature.
About the Speaker
Sabine Hossenfelder is a science communicator with a PhD in physics. She is the author of the books Existential Physics: A Scientist’s Guide to Life’s Biggest Questions and Lost in Math: How Beauty Leads Physics Astray.