This article is based on a talk given at the August 24 “Eco-Socialism Conference: For the Planet to Live, Capitalism must End,” hosted and organized by the Albuquerque branch of the PSL.

In the summer of 2012, the Waldo Canyon fire came close enough to my parents’ house that smoke and ash blocked out the daylight. There was so much ash falling into local reservoirs that tap water ran yellow for weeks.

We packed our photos and family heirlooms and stored them in the garage in case we were ordered to evacuate. But after a few tense days of waiting, the winds shifted, and the fire was contained. The dry forest around our house was spared, though the black scar of the fire is still visible today.

At the time, the Waldo Canyon Fire was the most destructive fire in Colorado history. But it was surpassed by the Black Canyon Fire the very next year. In fact, the summer of 2013 also saw the most destructive flood in Colorado history, a 1000-year weather event from which many parts of rural Colorado still haven’t completely recovered.

The most notable thing about these disasters is that you probably don’t remember them. Over the last decade, there have been so many extraordinarily destructive wildfires, hurricanes, droughts, blizzards, and floods− that it’s gotten hard to keep track.

Catastrophic weather events that were once rare have now become routine. Nine of the hottest years on record have occurred in the last 10 years, and we’ll likely claim all 10 spots by the end of 2019.

Climate change is here, happening all around us. It presents a greater and more credible threat than any other seen in the history of our species. Climate change has the potential to harm billions of people on this planet, drive mass extinctions, and upend existing power structures.

As socialist organizers, we must understand the science behind climate change as well as the social and political need to avert it. In this talk, I’m going to give an overview of how climate change works and the different possible outcomes we could see depending on the action we take right now.

The rise of capitalism brought with it the unrestrained extraction and consumption of land, timber, and fuels like coal. Burning fossil fuels releases carbon dioxide gas into the air. The most basic mechanism of climate change, warming, occurs because the layer of greenhouse gases, like carbon dioxide and methane, acts like a blanket, trapping the sun’s heat near the surface of the earth.

Since the onset of industrial capitalism 600 billion gigatons of carbon has been released into the atmosphere. Global temperatures have risen by approximately 1.3 degrees C, and if it weren’t for the cooling impact of a volcanic eruption in the early 2000s, would have likely risen by 2 degrees C, bringing us close to an oceanic & atmospheric status quo that’s unprecedented in history except for in periods of mass extinction, massive volcanic activity, or meteor impact.

No human being in the history of our species has experienced the atmospheric conditions we are seeing today. It is not an exaggeration to say that the survival of the human species, as well as countless others, is at stake.

The global climate is extraordinarily complex and exists in a delicate balance. As climate impacts intensify, scientists are discovering new, troubling repercussions of the capitalist system’s impact on oceans, ice, and all life on the planet.

Let’s start with ocean acidification: 70 percent of our planet is covered in water and ~40 percent of carbon emissions are absorbed by the ocean. When CO2 gas reacts with seawater, it produces carbonic acid, changing the pH of the ocean.

Acidic ocean water has devastating effects because it makes it difficult for any organism that uses CaCO3 to build its body, like phytoplankton or coral, to grow. These keystone organisms provide irreplaceable nutrients and habitats, making it possible for entire ecosystems to exist.

These small sea creatures also produce sulfur compounds crucial to seeding clouds. Fewer sulfur compounds means fewer clouds, which will in turn reduces reflection of the sun’s rays back into space and accelerates warming.

One way the planet regulates its temperature is by reflecting the sun’s rays back into space. Just like a white shirt reflects sun and keeps you cooler than a black shirt, parts of the earth that are covered in ice reflect more solar radiation than exposed land. This is called the solar albedo effect.

But it’s not only ocean acidification that’s adversely affecting the reflection of the sun’s rays. Polar ice is also melting at a speed that far outpaces even the worst-case models of many climate scientists. As we lose ice on the poles and in glaciers, we absorb more heat, and ice melts faster.

This is especially dangerous because there are some 1.8 trillion tons of carbon trapped in the arctic permafrost, more than twice what is currently trapped in earth’s atmosphere. If the permafrost melts, it could be released as methane, a gas that could have a warming effect 86 times more powerful than CO2. And all of this is happening on a timeline that keeps getting moved up.

In the 1990s, 2 degrees of warming- a level at which tens of millions of people would be displaced, the global food supply would be strained, and whole ecosystems would be irreversibly damaged – used to be our idea of an absolute limit. Today it is presented as a rapidly disappearing best case scenario.

The median projection of the most recent UN report on climate change puts us at 4 degrees of warming by the end of the century. Other credible studies suggest we could see 8 degrees of warming. Scientists still don’t know how to account for the potential release of methane from the arctic permafrost. But these numbers − 2, 3, 4, degrees etc. − are unremarkable and difficult to contextualize on their own.

So, scientists have put together data from more than 6000 peer reviewed studies to illustrate how different these possible outcomes really are. For example:

Should the world warm by 1.5 degrees Celsius, which could happen by 2040 if emissions don’t drastically change, all coral reefs on the planet would die out.

At 2 degrees, polar ice melt will reach a tipping point, flooding dozens of the world’s major cities. Intense drought could cause 400 million people to lose consistent access to water.

At 3 degrees, better than we would do if all nations honored their Paris commitments, wildfires would increase by 6x in the United States, and damages from river flooding would increase by 30-60x worldwide.

The last time the earth was 4 degrees warmer, sea levels were an average of 100 feet higher. At 4 degrees of warming, our median projection based on current trends, global grain harvest would be cut in half, and there would be 8 million annual cases of Dengue Fever in Latin America alone.

250 million years ago, when carbon warmed the planet by 5 degrees, it triggered the extinction of 97 percent of life on the planet.

The point of drawing out the consequences of these warming scenarios is not to make people panic, despair, or avoid thinking about the future. The point is to highlight that the science of climate change clearly shows it’s not a question of whether we are screwed. It’s not a binary, and the degrees really make a difference.

The operative question is, how fast and to what degree can we stop corporations from destroying the planet. And I chose the word corporations, not the general term ‘humans,’ because 70 percent of global greenhouse emissions are produced by just 100 companies. We cannot mince words about that fact. We don’t have the luxury of squandering time, or denying the problem, or waiting for the people responsible for this disaster to start caring.

The scale of the disaster we will face, and that our children will face, is still unknown to us. What is known, and what we must find strength in, is that we have no choice but to fight the capitalist system that has brought our planet’s ecosystem to the brink of collapse.