Environment

What Exactly Is Climate Change, Who's Causing It, and How Is It Affecting Us?

October 27th 2014

Climate change is one of the most dangerous threats facing current and future generations, but many people don't understand what climate change is, how it's already affecting us, and  what we can do about it. So we asked Ben Schneider, Communications Director at Defend Our Future, a non-profit with a mission to persuade politicians to protect our environment, to answer 10 questions that explain what's happening to our world.

  1. What is Climate Change?

The verdict is in: the Earth’s climate is changing, and humans are the main cause.

Over the last century, the average temperature of the planet has jumped 1.4 degrees Fahrenheit. Climate scientists are in agreement that the temperature rise has mostly been caused by the large amounts of greenhouse gases, such as carbon dioxide, that have been released into the atmosphere by humans since the Industrial Revolution.

You can think of greenhouse gases basically working like a giant blanket around the planet: they keep heat trapped in the atmosphere. The more gas, the more heat gets trapped. And scientists are warning us that if humans continue to pump greenhouse gases into the atmosphere, the Earth’s climate will continue to change.

It might not sound like the temperature is rising all that much, but think about how you feel when you get a fever – even a rise of 1 degree in your body temperature can make a huge difference in your health, right? The planet is sensitive to even small temperature shifts, as well. They can lead to stronger storms, the spread of insect-borne disease, sea level rise and a lot more.

  1. I heard that Earth’s climate has always changed! I mean, there was an Ice Age! Why is the current warming of the planet any different?

You are correct—natural forces have caused Earth’s climate to change in the past. The climate warmed as the earth’s orbit shifted closer to the Sun, and it cooled after volcanoes erupted and emitted sunlight-reflecting particles. An increased presence of greenhouse gases in the atmosphere released from ice and the oceans also caused the climate to warm.

What distinguishes now from other times of climate fluctuation in the Earth’s history? Greenhouse gases are being released into the atmosphere at an unprecedented rate, and they are being released by human – rather than natural – activities. Since the industrial revolution, humans have released so much carbon dioxide into the atmosphere that levels are now higher than they have been in the last 650,000 years. Not coincidentally, 97 percent of climate scientists agree climate change trends during the last century are due to the massive amounts of greenhouse gases human activities are releasing.

  1. If temperatures have been changing since before humans even walked the Earth, how can you say that we are causing climate change?

Just because the climate has changed in the past does not mean that human activity has not caused the current warming of the planet. Any activity that changes Earth’s energy balance can change the climate, and human emissions of greenhouse gases changes the energy balance. Prior to the Industrial Revolution – around 1750 – atmospheric carbon dioxide levels rose by less than 10%. Since then, levels have risen a whopping 43%. Burning coal, natural gas, oil and gasoline account for 85% of human-produced carbon dioxide.

  1. Has anything happened already? What’s going to happen to the world if climate change continues?

We are already seeing the effects of climate change, in the United States and around the world. Heavy storms have become more common because there is more moisture in the atmosphere in a warmer world. Floods, droughts and heat waves are more intense and/or frequent. The world’s ice caps are melting and the oceans are getting warmer. Sea levels are rising.

As scary as things are now, it’s going to get much, much worse in the future if we don’t do something about it. Average temperatures could rise up to 11.5 degrees Fahrenheit over the next century. Sea levels could rise up to four feet on average (even more than that in some areas, like the Northeast U.S. coast.) Heat waves, hurricanes, droughts, floods… all of it will become more common and/or more severe.

This is all very bad: it’s going to be much harder to produce food under these conditions, and entire species will face extinction as their natural habitats disappear.

  1. If the planet is supposedly getting warmer, why is it so cold where I live? 

First we must draw a distinction: weather and climate are different things. Weather refers to daily events, whereas climate refers to the average temperature and conditions over many years. While there may be cold weather spells where you live, the average temperature worldwide is rising. In fact, 2001-2010 was the warmest decade in recorded history. (Click below to watch Neil deGrasse Tyson explain weather vs. climate.)

  1. Okay, so I’m convinced: climate change is real. But why should I care? How does it affect me and my life? 

You’re going to face different challenges depending on where you live, but it’s going to get rough all over: heat-related deaths, storm surges, great difficulty growing certain crops, wildfires, several feet of sea level rise, shorter ski seasons and fewer beaches, damaged infrastructure… the list goes on. Climate change is going to make things worse for all of us, no matter where you go.

  1. Do we have to choose between fighting climate change and keeping jobs?

The good news is that countries the world over have a chance to put policies in place that will prompt economic growth and reduce climate change risk. The bad news is we need to act very, very quickly. The Global Commission on the Economy and Climate, which is advised by some of the world’s foremost economists, says the next 15 years will be a critical juncture. Smart policies by the world’s leaders can promote a “low carbon economy” for the global economy. Failure to do that means climate change could continue unchecked, with potential devastating consequences by the end of the century.

  1. Can’t we just use technology to cool the climate?

This is called “geoengineering” – using technology to do things like suck the greenhouse gases out of the atmosphere faster than we put them in. Another idea is to pump reflective particles in the atmosphere to reduce how much heat we get on the planet in the first place – block out the sun, in other words.

Does that sound scary? It is. There’s no guarantee it would work. And trying any of this is a huge risk that might have terrible side effects and unforeseen consequences. And it wouldn’t do a thing to stop other climate change issues that have nothing to do with temperatures, like ocean acidification.

  1. Did climate change cause Hurricane Sandy, the 2013 floods in Colorado, or the current drought in California?

Climate change is making events like these worse. The increased frequency and severity of occurrences like hurricanes, flooding, heat waves, and wildfires are caused by climate change.

For example: while we don’t know whether or not climate change caused Hurricane Sandy, the powerful storm surge that caused massive destruction was certainly worsened by rising sea levels caused by the melting of mountain glaciers and polar ice sheets, along with expanding water molecules in a warmer ocean. Those all are due to climate change.

Colorado’s 2013 floods were exacerbated by the preceding hot and dry summer, which hardened the soil and eliminated vegetation—two things that usually help absorb and slow rainfall.

And in the case of the California drought, a recent study suggests that there is 95 percent confident that human-caused climate change tripled the chance of the development of a persistent high pressure system in the Northern Pacific Ocean, which is the cause of the California drought because it deflects precipitation away from the region.

  1. What can I do to fight climate change?

Tell elected officials that you care about this issue, and want action

There are also lots of fantastic environmental non-profit groups, such as the Environmental Defense Fund, you can get involved with that would love to have your support!