Back in 1987, literally every world government came together to address a global atmospheric crisis: ozone depletion due to use of chlorofluorocarbons (CFCs). This was known as the Montreal Protocol and led to a shift from CFCs—used mainly in air conditioning (AC) units and aerosol sprays—to hydrofluorocarbons (HFCs), which do not react with ozone molecules but are still potent greenhouse gases. The fear now is that developing nations are expected to massively increase penetrance of AC units in their households.

As Helena Molin Valdés, head of the United Nations's Climate & Clean Air Coalition Secretariat in Paris, explains, "If we continue [the exponential growth in refrigeration and air conditioning demand], we will put great pressure on the climate system." As an example, India is expected to increase the number of households with AC by about 105 million by 2050, an increase of more than 400% from today's 20 million. In other words, as air conditioning usage increases exponentially, so will not only their carbon footprint but also the release of HFCs, which can be 1300 times more potent than CO2 in trapping atmospheric heat.

A solution in sight?

AC usage is not just a banal modern comfort, it can be life-saving as lethal heat waves are expected to increase in the coming decades. By the time 2100 rolls in, between 48 to 74% of the world's population is expected to face deadly heat waves. Since AC usage cannot be safely reduced, a 2007 amendment to the Montreal Protocol called for replacing HFCs for less climate-warming substitutes. But that is easier said than done.

On top of HFCs, hydrochlorofluorocarbons (HCFCs), which are not only greenhouse gases but also deplete ozone, are still widely in use. Under the 2007 amendment to the Protocol, developed nations are expected to eliminate HCFCs by 2020 and reduce HFCs by 85% by 2036. Still, a federal appeals court in the USA has already rejected an Environmental Protection Agency rule compelling manufacturers to replace HFCs. Because we mustn't interfere with private profits, even when the costs end up being socialized. Especially when the costs can be socialized.

Developing nations, on the other hand, have a little more leeway. They are expected to phase out HCFCs by 2030 and HFCs by 2047, making some climate experts hopeful that they may be able to largely skip the usage of HFCs altogether. Again, we can center on India, a country currently developing a national plan to better city planning and building design, and favor the usage of more climate-friendly coolants as HCFCs are phased out.

Read more here:

"As countries crank up the AC, emissions of potent greenhouse gases are likely to skyrocket" at Science News