Skip to Content

Debate Needed to Address Global Warming Uncertainty

A Norwegian study counters previous estimates of how sensitive the planet is to greenhouse gases.
January 28, 2013

Over the weekend, a Norwegian climate change study from last year got a fair amount of attention online, thanks to what appears to be a new English translation of a press release from October. The work incorporates data from the last several years, during which global temperatures remained fairly steady. It suggested that the climate may not be as sensitive to carbon dioxide levels in the atmosphere as previously thought. If carbon emissions double from pre-industrial levels, the world might warm by 1.9 ° C, which is on the low end of a range of estimates from the Intergovernmental Panel on Climate Change.

The good news is tempered by the fact that greenhouse gas emissions are increasing, which means greenhouse gas levels could more than double, even if the world acts to quickly reduce emissions (see “Solving Global Warming Will Require Far Greater Cuts than Previously Thought”).

It’s also tempered by the fact that this study, like all climate change studies, aren’t certain, but are estimates. It’s difficult to for climate scientists to predict how greenhouse gases will affect the climate because the climate system is so complex. Scientists are still learning how clouds will respond. The role of emissions other than carbon dioxide is also unclear. For example, a recent study suggested that black soot could have a bigger impact on climate than thought. The study in Norway itself doesn’t actually give one figure for warming, but a range of possibilities—including possible warming levels higher and lower than 1.9 ° C, because of the uncertainty involved.

Add to this uncertainty the uncertainty of what even 2 ° C would do to the weather and the uncertainty about how much it will cost to wean the world from fossil fuels.  

This all makes establishing sound policy difficult, to say the least. Scientists have a high degree of confidence that anthropogenic greenhouse gases are responsible for a large share of the roughly 1 ° C rise in temperatures we’ve seen so far, and that it will lead to warming in the future. Since no one can say precisely how much, and that’s why it’s so important to have a high level, prominent discussion in the United States and around the world about the risks of climate change, and how best to respond (see “Obama Still Needs to Make the Case for Dealing with Climate Change”).

Keep Reading

Most Popular

This new data poisoning tool lets artists fight back against generative AI

The tool, called Nightshade, messes up training data in ways that could cause serious damage to image-generating AI models. 

Rogue superintelligence and merging with machines: Inside the mind of OpenAI’s chief scientist

An exclusive conversation with Ilya Sutskever on his fears for the future of AI and why they’ve made him change the focus of his life’s work.

The Biggest Questions: What is death?

New neuroscience is challenging our understanding of the dying process—bringing opportunities for the living.

Data analytics reveal real business value

Sophisticated analytics tools mine insights from data, optimizing operational processes across the enterprise.

Stay connected

Illustration by Rose Wong

Get the latest updates from
MIT Technology Review

Discover special offers, top stories, upcoming events, and more.

Thank you for submitting your email!

Explore more newsletters

It looks like something went wrong.

We’re having trouble saving your preferences. Try refreshing this page and updating them one more time. If you continue to get this message, reach out to us at customer-service@technologyreview.com with a list of newsletters you’d like to receive.