Could hydrogen leaks affect the Earth’s ozone layer?

Hydrogen pipelines [image credit: US Department of Energy @ Wikipedia

This is one of several questions to be investigated by a Norwegian research team. The ultimate one may be: what happens to hydrogen’s hoped-for role in the big push for so-called green energy, if the findings are unfavourable to current climate theory?
– – –
Hydrogen is an attractive [Talkshop comment: perhaps, but expensive] alternative to fossil fuels, especially for powering trucks, ships and planes, where using batteries isn’t so easy, says TechXplore.

Hydrogen is an attractive alternative to fossil fuels, especially for powering trucks, ships and planes, where using batteries isn’t so easy.

Batteries quickly become too large and heavy if these large transport vessels and vehicles are going to travel far.

As a result, hydrogen is being discussed like never before. Both Norway and the EU have said they will invest more in hydrogen in the years ahead.

But a lot needs to happen before hydrogen actually becomes climate-friendly. And it’s not just about how hydrogen is made, which is one of the challenges the Norwegian government highlighted in its Hydrogen Strategy released in the summer of 2020.

One thing that is rarely discussed is the hydrogen gas itself. What happens when it leaks into the surroundings?

Researchers at Cicero, the Center for International Climate and Environmental Research in Oslo, are in the process of finding the answers to these and other questions about hydrogen in a new research project.

The world’s lightest gas

“It’s important that we be aware of the effects that hydrogen can have on the climate and environment, before we start with large-scale production and use. That way, we can avoid making the same mistake as we did when we started using chlorofluorocarbon gases, which would later prove damaging to the ozone layer,” said Maria Sand, a Cicero researcher who is leading the new project.

Some of the hydrogen will inevitably leak out during production, transport, storage and use.

“Hydrogen is the lightest gas in the world, so it’s impossible to prevent leaks,” she says.

May affect the big picture

This concept is probably new to many, including politicians and scientists.

“People often think that there are zero emissions from hydrogen, since it is not a greenhouse gas,” Sand said.

Hydrogen does not on its own trap heat inside the atmosphere the way that CO2 and other greenhouse gases do.

But hydrogen can still affect the big picture. At least in theory.

Will calculate the effect with climate models

Researchers at Cicero started the new project in collaboration with both industry and several international research groups.

Sand says when she and her colleagues first began to examine the issue, she was surprised by what they found. The existing studies suggest that hydrogen emissions could have a negative effect.

“Even though hydrogen is not a greenhouse gas, it can affect the composition of the atmosphere,” she says.

But the extent to which this is happening—or could—is still uncertain.

“We don’t know if the effect is large, but we also don’t know if it’s small either,” Sand said.

So researchers at Cicero reached out to other scientists who have studied the issue in the US and Europe, so they could collectively put their heads together.

The plan is to calculate the answers using five different climate models. They will also use real measurements of hydrogen in the atmosphere to check if their calculations are correct.

The ozone layer can be damaged

The researchers will look at a range of possible effects.

The first is that hydrogen can potentially damage the ozone layer.

The gas can cause beautiful clouds to form in the sky. But the explanation for why the clouds form is not so beautiful.

When hydrogen is released into the air, it is often converted to water. This can happen high in the stratosphere, where the ozone layer is.

“The ozone layer is very dry, but some reactions with hydrogen cause can water vapor to form there,” Sand says.

This is not good news for ozone.

What happens is the same as when the weather is very cold, which can cause pearlescent clouds to form in the sky.

These colorful clouds are actually evidence that the ozone layer is being broken down.

Continued here.