Can we fix climate change with new technologies?

Make clouds whiter or release particles into the air to combat global warming. They are examples of Geological engineering or Climate engineering, or interfering with the Earth’s natural systems. The goal is to combat climate change. It looks futuristic, but it may not be so soon.

TU Delft begins the year with a major research in climate engineering. Together with Britain’s University of Cambridge, they will spend the next six years researching how to make clouds whiter.

The theory is that white clouds reflect more sunlight. This would cool the Earth. “We will investigate whether they work and what are the implications and risks of these technologies,” says Professor of Atmospheric Research Hermann Rauschenberg from TU Delft.

A cloud can consist of many small droplets, or a smaller number of large droplets. “Sunlight falling on a cloud with much smaller droplets is reflected better than sunlight on a cloud with fewer but larger droplets,” Rauschenberg explains.

The professor wants to use his research to change the clouds over the sea. “You can pump salt crystals out of the sea, break them up, and then blow them into a cloud,” says Rauschenberg. This way you get more of the smaller droplets in the cloud, making it whiter and more reflective than normal. This is how the Earth cools. This is called Brightening the marine cloud.

In the coming years they will investigate whether this really works in Delft. “We want to see if it’s technically possible, using salt crystals. Then we want to see if it really has a cooling effect and if there are any unintended side effects,” says Rauschenberg. For example, rain patterns can change due to human intervention.

In the United States, the government also has a large Research programme Launched. Over the next five years, research will also be carried out there into technologies to combat the consequences of climate change.

This concerns, for example, the so-called stratospheric aerosol injection, in which sulfur particles are introduced into the stratosphere, kilometers above the Earth.

“They scatter around the Earth and block sunlight. About 1 to 2 percent of the sunlight, which causes the temperature to drop on Earth,” says Claudia Wieners, a researcher at the Institute for Sea and Atmospheric Research at Utrecht University. “These particles stay in the stratosphere for about a year. Then you have to do it again, otherwise the effect is gone.”

Stratospheric aerosol injection has not yet been tried. “Once Harvard scientists did a test. They wanted to put a balloon with two kilograms of lime dust in the atmosphere and see how the particles would spread,” Wieners says. But this experiment stopped because there is great resistance to it ».

Now that there is more research on the new possibilities, the resistance against them is also growing. Hundreds of scientists have signed one Call Internationally agree not to use geoengineering. “We can never fully quantify the risks of these technologies,” says Frank Biermann, Professor of Global Sustainability Management at Utrecht University and one of the initiators of the petition.

“Who decides if we’re going to use it? We don’t have a structure for that at all,” Berman says. Many people also fear that there will be no incentive to stop using fossil fuels if climate engineering becomes popular.

“This is definitely not the answer to the climate problem,” Wieners says. “We need to stop the greenhouse gases, but we also need to explore how we can combat the consequences, global warming.”

Reporter Daisy Mohr visited a center in Abu Dhabi late last year and went to photograph the clouds with pilot Ahmed Al Jabri:

Hermann Rauschenberg believes that research should be done before ideas can be put forward. “If you soon have a land that is too hot to live on and you don’t look for solutions, you will be left empty-handed.”

According to him, if the theory is correct, the temperature can be lowered by one degree Cloud brightening. “These technologies are more than a tool for keeping Earth livable in the future.”

They will first start with theoretical studies in Delft, with the first trials likely in 2024. This will be the first time that a theoretical Brightening the marine cloud It is being put into practice. If the results are promising, the question arises of how this might be used in the future.

“Science provides knowledge, and those in charge need to think about how that knowledge is used,” says Rauschenberg. “But if you find these kinds of styles and it gets warmer, people want to use them.”