The Word I Found in a Job Application

5 days ago

6 min read

This week I was applying for a position with the United Nations. A Programme Specialist role with the Climate and Clean Air Coalition in Paris. As I read through the job description, one term kept appearing. Short-lived climate pollutants.

I teach ESG and sustainability for a living. I have read my share of climate science. But this phrase stopped me, because I realised I could not explain it to a student in one clean sentence. So I did what I always do when a word humbles me. I spent the evening learning it properly. And what I found genuinely surprised me, because hidden inside this slightly awkward technical term is one of the most hopeful ideas in climate action today.

Let me take you through it the way I would in my classroom.

First, the problem with how we talk about climate

When we say climate change, most of us think of one gas. Carbon dioxide. And that is fair. CO2 is the biggest driver of warming and it stays in the atmosphere for centuries. Every tonne we emit today is, quite literally, a problem for our grandchildren.

But CO2 is not the whole story. There is a group of other pollutants that warm the planet far more aggressively than CO2, kilogram for kilogram. The reason we do not fear them in the same way is that they do not stay long. They do their damage quickly and then they are gone.

These are the short-lived climate pollutants. SLCPs, if you like acronyms. The Climate and Clean Air Coalition, the CCAC, says they are the most important contributors to human-caused warming after carbon dioxide. Together they are responsible for up to 45% of the warming we are experiencing right now.

Almost half. From pollutants most people have never heard of.

Meet the four main culprits

Methane. You know this one from the news. It comes from oil and gas operations, landfills, wastewater, and livestock. Over 60% of methane emissions come from human activity, and agriculture is the largest human-made source. Here is the part that matters. Over a 20-year period, methane warms the planet about 86 times more than CO2 for the same weight. But it only lives in the atmosphere for around 12 years. Compare that with CO2, which lingers for centuries.

Black carbon. This is plain soot. The dark smoke from diesel engines, brick kilns, forest fires, and the chulhas and wood stoves still used in millions of homes. It stays in the air only for days to weeks. But while it is there, it absorbs sunlight and heats the atmosphere, and when it settles on snow and glaciers it makes them melt faster by darkening them. In Asia and Africa, 60 to 80% of black carbon emissions come from residential solid fuels, which means this is as much a household health issue as a climate one.

Hydrofluorocarbons, or HFCs. These are the gases inside your air conditioner and refrigerator. They were brought in to replace the older gases that were destroying the ozone layer, and they did that job well. The catch is that HFCs themselves turn out to be powerful greenhouse gases, hundreds to thousands of times stronger than CO2. The world fixed this diplomatically in 2016 through the Kigali Amendment to the Montreal Protocol. If fully implemented, Kigali alone is projected to prevent up to 0.5 degrees Celsius of warming by 2100.

Tropospheric ozone. This one is different because nobody emits it directly. It forms in the lower atmosphere when sunlight cooks together pollutants from vehicles and industry. You know it as the main ingredient of smog. It lives for only hours to weeks, but it damages lungs, crops and ecosystems while it warms the planet.

Why short-lived changes everything

Here is the idea that made me sit up.

Because these pollutants disappear quickly, cutting them gives results quickly. If we slash methane emissions today, the atmosphere notices within about a decade. It is one of the very few climate actions where we can see the benefit inside our own working lives.

The numbers are not small. The UN Environment Programme's Global Methane Assessment found that human-caused methane emissions can be reduced by up to 45% this decade using measures that are largely available and affordable. Doing that would avoid nearly 0.3 degrees Celsius of warming by 2045. More than 155 countries have already signed the Global Methane Pledge to collectively cut methane 30% from 2020 levels by 2030, a step that by itself could eliminate over 0.2 degrees of warming by 2050.

In climate terms, a few tenths of a degree is enormous. It is the difference between a coral reef that survives and one that does not.

And there is a bonus that does not get enough attention. These pollutants are also air pollutants. The same methane that warms the planet creates the smog that triggers asthma. That 45% methane cut would prevent an estimated 260,000 premature deaths and 775,000 asthma-related hospital visits every year, along with avoiding 25 million tonnes of crop losses annually. Cut black carbon and you clean the air inside homes where women and children breathe cooking smoke every day.

This is climate action that pays its first dividend at the local clinic, not just at the North Pole.

So what does the CCAC actually do

This brings me back to the job application.

The Climate and Clean Air Coalition was founded in 2012, after a 2011 study by UNEP and the World Meteorological Organisation showed both the harm these pollutants cause and how quickly reducing them pays off. Six governments started it - Bangladesh, Canada, Ghana, Mexico, Sweden and the United States - together with UNEP. Today it is a voluntary partnership of more than 200 governments, international organisations and NGOs, convened within UNEP, working in over 90 countries.

Their job is exactly what the name says. Climate and clean air, together. They fund national action plans, push sector solutions in agriculture, cooling, waste, transport and fossil fuels, run the science assessments that tell governments where the cheapest cuts are, and host the Secretariat of the Global Methane Pledge.

The role I applied for sits inside this machinery. I do not know yet whether I will get it. But here is what I know already. The evening I spent reading their work changed how I will teach.

Why this gave me hope, and I think it will give you hope too

Climate news usually arrives as a list of things that are too big, too slow and too late. SLCPs are the opposite story. The sources are known. The solutions exist today. Many of them save money. And the results show up fast enough to matter for us, not only for people born in 2080.

Does this replace CO2 reduction? Absolutely not. CO2 is still the main course, and we must decarbonise energy, industry and transport with everything we have. But SLCP cuts are the fastest lever we can pull while that longer work continues. Think of it this way. CO2 reduction is how we win the century. SLCP reduction is how we buy the time to get there.

When I teach my next ESG batch, this is going in the curriculum. Not as a footnote under "other greenhouse gases", but as its own module. Because when a student asks me what one person, one company or one city can do that actually bends the curve soon, I finally have a complete answer. Fix methane leaks. Clean up cooking and heating. Phase down HFCs properly. Cut the black smoke. Measure it, report it, own it.

That is what we work on at Sustainability 101 too. If reading this makes you want to go deeper into how emissions are measured, reported and reduced, take our GHG Accounting Bootcamp. We teach you everything step by step, from Scope 1, 2 and 3 calculations to targets and carbon markets. You can find it here: https://www.sustainability101.in/ghg-bootcamp

Sometimes a job application gives you a job. Sometimes it gives you a new way to see your work. This week, for me, it did the second. And honestly, that already feels like a win.