Proposing 'paradoxical': Discharging more CO2 can limit climate change

Carbon dioxide is increasingly concerned. The reason is, on May 11, the CO _{2 content} in the air reached 415 parts per million (ppm), 100 ppm higher than our typical atmospheric concentration over the past 800 thousand years. Now, even if we stop emissions, greenhouse gases will still warm up the Earth for thousands of years.

However, some scientists believe that methane, a greenhouse gas, is a "hands-on" solution to stabilizing our climate . In one study, scientists from Stanford University (USA) argued that we could limit global warming by converting methane to carbon dioxide.

Methane, or CH ₄ , currently has air concentrations of 1,860 parts per billion, about 2.5 times higher than before the Industrial Revolution. 60% of methane emissions are caused by humans, from agricultural activities as well as fossil fuel production. This gas exists for a short time in the atmosphere, an average of a decade, but "hard-working" to heat things up during that time. Methane warms the atmosphere 84 times CO ₂ in 20 years and 28 times in a century.

Scientists believe that methane, a greenhouse gas, is a "hands-on" solution to stabilizing our climate.

Molecular chemistry turns methane into a greenhouse gas, but this is also a potential solution, the researchers argued. Methane combines with oxygen to produce carbon dioxide and water, releasing energy. This reaction occurs naturally in the atmosphere. If we can create an industrial process that accelerates this natural trend, this could be an important strategy in slowing global warming, the study suggests.

On the surface, this may look like the proposed designs for direct carbon capture - huge fans suck and then draw air through a means to help methane convert into CO2. Unlike carbon recovery, waste gas does not need to be pumped in and stored. Instead, carbon dioxide will naturally "born" . Because carbon dioxide is a weaker greenhouse gas than methane, the net impact will still be to reduce global warming. Converting all human-induced methane in the atmosphere will release an additional 8.2 billion tons of CO ₂ , the amount we emit globally for several months. However, this process will cut about one-sixth of global warming that we have experienced since the start of burning fossil fuels, the study estimates. "This will give us time to tackle tougher carbon dioxide sources," said Rob Jackson, the lead researcher.

Of course, this proposal is only in the concept stage and there are still many challenges to implementation. According to the study, one of the most obvious challenges is that methane gas diffuses in the air. At concentrations of 1,860 ppb, methane is a very small fraction of all air molecules and about 200 times more diluted than carbon dioxide.

The chemical structure of methane is also a barrier to conversion. With tetrahedral shapes - four hydrogen atoms branching from one carbon in the center, methane has no contact point for the catalyst. However, there is some promising evidence that it is possible to use zeolite, a mineral with a pore system to convert methane gas. The tiny pores of zeolite can help wet methane gas and react with metal catalysts, facilitating the conversion into CO2.

Like carbon capture, this process can use a lot of energy. Construction of equipment, exploitation of zeolite and operation of the fan system will require power. According to Jackson, the methane conversion system will run ideally on non-carbon sources, such as wind and solar. And, because the reaction has released energy, he believes that it is possible to capture and use that energy to stay active.

Finance is also a problem. Currently, the release of carbon into the atmosphere is basically free, so there is no way to make money from this process. A decree from the government or setting a price for carbon would be necessary to increase the scale of methane capture. As research shows, at a price of $ 500 per ton of CO2, the process of reducing global warming generated by converting methane to carbon dioxide will yield $ 12,500 per ton of converted methane gas.

Some people think that relying on carbon prices is too optimistic, and we should spend money on renewable energy."This idea is very heavy in material and energy and cannot compete even with carbon prices greater than 500 USD / ton," said Sgouris Sgouridis, industrial engineering scientist at the University of Khalifa. "Why pursue a very expensive strategy instead of expanding a cheaper strategy?"

Because methane is short-lived, let it be handled naturally."There is a much simpler solution for CH4's contribution to global warming," Pieter Tans, director of the Carbon Cycle Group NOAA. "I propose we reduce CH4 emissions in known ways and let the atmosphere handle oxidation to CO2 for about 10 years."

According to Mr. Jackson, technology, even with its challenges, may have an important climate position in the future. He hoped his proposal would source research on ideal materials to catalyze methane conversion and ideas for industrial facilities to concentrate methane gas, making it more reactive. For Jackson, it was not just about trying to stabilize the heating planet. This technology may even play an important role in continuing to cut our emissions, in "restoring the atmosphere." "I think repairing the atmosphere is a better strategy than stabilizing it."