why 2 degrees is so important – my opinion

“Who knows the perfect temperature for humans on this planet? I wouldn’t mind if it were warmer,” argued one businessman at a roundtable on climate change I was hosting at a conservative Christian college. With a foot of snow on the ground that morning, there were nods all around the circle; who wouldn’t want warmer weather?

Given the wild weather swings we’ve all experienced, two degrees seems like a small, even potentially negligible temperature rise. When we talk about two degrees, though, we have to realize we’re not talking about weather: we’re talking about the average temperature of the planet. And, over the course of human civilization, the planet’s temperature has been almost as stable as that of the human body.

What happens if our own temperature—or that of our child—suddenly spikes up by two degrees Celsius, three and a half degrees Fahrenheit? Most of us would call the doctor, or (if we were a new parent) maybe even head to the emergency room. We know that even with an average temperature of 98oF, an increase of 3.5oF means something’s seriously wrong; and that’s exactly what’s happening to our planet.

What will a warmer world look like?

I study the impacts of climate change. My research, and that of my colleagues, puts the numbers on how it’s affecting our water resources, our food and crop yields, the economy, and even our health. I take those numbers and I parse them out: what will the world look like, if it warms by 1oC? 2oC? Or 3oC?

In a two degree world, record-breaking hot, dry summers could become the norm across the central United States; around the world, corn and wheat yields could drop by an average of 10 to 30%; and faster evaporation and shifting rainfall patterns could decrease runoff across much of the central and western U.S. by 10 to 30%. The intensity and strength of hurricanes scales with global temperature, as does the duration of heat waves, the risk of wildfire, and even the growth of phytoplankton in the ocean, the base of the food web on which hundreds of millions of people depend.

Is this dangerous? That’s up to us to decide. To make that decision, we need science—and we need more. We need both our hearts and our heads. What’s the right thing to do when confronted with a global challenge that is already—at less than 1oC of warming—increasing the risk of suffering and even death for the poor, the marginalized, and the disadvantaged around the world?

The ethics of climate change

People of faith understand injustice, and understand the right thing to do when we see it. That’s why the roundtable at the conservative Christian college on that snowy day wasn’t about the science of climate change: it was about the ethics of climate change. And that’s why, when I went to the climate negotiations in Paris (COP21), I didn’t just go as a scientist. I went as a human, concerned for the welfare of my fellow citizens around the world; and I went as a Christian, believing that God has given us responsibility to care for every living thing on this planet, which includes loving others as God loves us.

In Paris, I met many other humans—mayors of cities around the world, determined to make the right choice for the people for whom they are responsible; faith leaders, speaking out with unmistakable authority on the moral imperative for action; business and technology leaders, committing their resources to a better planet; concerned citizens, making the trek on their own dime (some, on their own feet or wheels) to raise their voice in support of what’s right; and most importantly of all, representatives from the Philippines, the Maldives, and many other nations already struggling with poverty, hunger, lack of access to clean water, basic education, and security who were there to bear witness to the real, the serious, and the profoundly dangerous impacts climate change is already having on their homes, their families, and their people.

The door is closing fast

Because all humans share these central concerns—because 195 nations around the world who have collectively realized that doing nothing about climate change will be far more expensive, both in dollars and in human lives, than acting now—the final text of the Paris agreement set a goal of limiting the rise in global temperatures to below 2°C, and to pursue efforts to limit warming to 1.5°C.

Are these goals physically possible? Yes—but that door is closing fast. Achieving a 2°C target will require serious commitments from everyone: from cities and states, countries and regions, and perhaps most of all, from the companies involved in extracting and producing the fossil fuels that are the main reason we’re in this situation to begin with. Unfortunately, though, many of those companies are not stepping up to the plate.

ExxonMobil is trying to block shareholders from voting on the issue

Take ExxonMobil, for example. Last month, it challenged a climate justice proposal put forth by a cross-section of faith-based investors, health systems, socially responsible asset management firms, and indigenous and community groups.

ExxonMobil not only refuses to acknowledge the moral imperative to limit global average temperature increases to 2°C above pre-industrial levels, it is actually attempting to prevent its shareholders from voting on the issue, claiming the request is “vague” and that it has already been “substantially implemented” anyways. But faith-based investors are not giving up. They are appealing to the Securities and Exchange Commission (SEC) to allow this resolution to appear on the ballot for ExxonMobil’s annual meeting this spring.

Achieving a 2oC target seems like a daunting task. But any emissions reductions we achieve will lead us in the right direction, towards a better world: for ourselves, for our families, for our country, and most of all for our brothers and sisters around the world. It’s clear that this is the right thing to do.

This essay originally appeared on The Equation, a blog of the Union of Concerned Scientists.