Climate change is accelerating (just as science announced 20 years ago)

The climate change Don’t go faster Than expected, contrary to confirmation I believed by the Secretary-General of the United Nations himself, Antonio Guterres. In fact, the interconnected relationship between the Scientific Projections and the Medium temperature and the sea level It’s very good. that some operations accelerate – Like sea level rise – is one of the expected scenarios. Some extreme events in recent years, especially intense heat wavesis also an expected consequence of emissions.

Undoubtedly, we are witnessing dramatic transformations in a long-known film. “Things are progressing as expected and that’s bad enough, sums up Roger Belkey, professor of environmental studies at the University of Colorado and critic of the climate disaster. “We don’t say that [el calentamiento] It happens faster than expected ” A spokesperson for the Intergovernmental Panel on Climate Change (IPCC)IPCC).

“Things happen faster than people expected, not what models predicted”

Gavin Schmidt, NASA

“People did not expect to see the impact of climate change on extreme weather events so soon. But the warming in the past 10 years is enough to generate them. Things happen faster What people expected, not what models expected Gavin Schmidtdirector of NASA’s Goddard Institute for Space Studies and author of A Analytics The quality of climate models. “We were starting to see the effects we already knew were coming,” he agrees Francisco Dublas ReyesDirector of the Geosciences Department at the Barcelona Supercomputing Center (BSC).

Global variables in acceleration

everybody The Analytics From the climate models used by the Intergovernmental Panel on Climate Change (IPCC) confirm that they were correct in simulating global climate variables: we have projected warming and sea level for the amount of emissions that resulted, within the range of Estimates go back to the 80s and 90s.

These forecasts have already indicated that the temperature, sea level and intensity of the water cycle will not only increase, but also accelerate. What is this? acceleration What is happening before our eyes has already been endorsed by the Intergovernmental Panel on Climate Change in its 2021 report.

regional phenomena

However, the models are not good at simulating climate at the regional level. On this smaller scale, the extreme events that cause the most damage and attract the most attention occur.

“Current simulations do not have sufficient accuracy. We do them on a scale 100 km And we’ll need it on one scale. For this, computers that do not yet exist are needed, says Doblas.

The extreme reduction in Arctic ice during the summer is probably the only process that is happening much worse than expected.

In addition, there are processes that have not been successfully simulated until a decade ago. For example, file Arctic amplificationThe set of phenomena that make the Arctic warm four times faster than the rest of the planet. The extreme decrease in Arctic ice during the summer is likely to be Only the process that happens is much worse than expectedBecause of this delay in prototyping.

extreme events

The anticipation of extreme events is perhaps the most relevant to climate policy. However, the modelsThey can’t help much it now.

“If you heat the atmosphere, it will hold more water, and this will intensify the extreme events. Models predict that these phenomena will be more frequent, but they are unable to simulate their magnitude and frequency. It’s good with averages, not extremes” Confirms Tim Palmera physicist at the University of Oxford.

“Models predict that extreme events will be more frequent, but are unable to simulate their magnitude.”

Tim Palmer, University of Oxford

For example, no model has warned that, with the current level of emissions, 50 degrees Celsius in Canada last year Or will they give Devastating floods in Pakistan this year. It’s not that these phenomena are happening sooner than expected. It’s just those models They can’t emulate it. To do that, we have to improve it, says Palmer. This researcher calls for a global scientific effort to make the simulation much larger than the current simulation.

Attribution problem

This leads us to a difficult question. If there are no models to justify this, how do we know if these phenomena are due to emissions-induced climate change rather than natural meteorological fluctuations? Herein lies the thorny problem attribution.

“The science of attribution is important and there is still work to develop,” Doblas says. In some cases, there is no doubt. Although simulations do not expect heat waves Extreme, yet they predict much less when a world without industrial emissions is simulated. Thus, it can be inferred that they must occur due to increased carbon dioxide. 50 degrees Celsius in Canada Impossible without climate change” researcher says.

“50 degrees in Canada is impossible without climate change”

Francisco Dublas-Reyes, Barcelona’s Supercomputing Center

Other phenomena are more complex. For example, file meteorological drought. “The natural variation in precipitation is so large that it has a greater impact than climate change,” Doblas explains. This does not mean that climate change does not increase evaporation, and thus exacerbate its effects.