You’ve probably already heard of climate change and global warming—but what are they, exactly?
New reports, scientific studies, and political rulings seem to come out every day, which makes it incredibly hard to keep track of the basics. And it’s even harder to understand what scientists know, what they think they know, and what has been spread by rumor and confusion.
Since we’re looking at similar topics at this year’s eStudies, Field Studies, and Summer Studies Programs, we’re offering a guide to the basics of climate change. (Don’t forget that the Field Studies and Summer Studies applications already opened, and eStudies opens on April 4!)
So, what is it, exactly?
The first thing to understand is global warming.
According to National Geographic, “the global average surface temperature has increased between 1.1 and 1.6 degrees Fahrenheit” since 1906. In other words, it’s exactly what it sounds like: the Earth is getting hotter.
Over the history of the planet, the Earth has gone through a number of different eras in which it warmed up and cooled off. But what we’re seeing today is far greater than anything we’ve seen before. And that’s because of the next thing to know: the Earth is getting hotter because of carbon emissions, which cause something called “the greenhouse effect.”
NASA explains it this way: “Certain gases in the atmosphere block heat from escaping. Long-lived gases that remain semi-permanently in the atmosphere and do not respond physically or chemically to changes in temperature are described as ‘forcing’ climate change.” In other words, those gases act like blankets, keeping the heat here instead of letting it evaporate into space, which warms the planet.
The chief gas in question is carbon dioxide, which is released into the atmosphere through the burning of fossil fuels like coal and oil, among other things. According to NASA, the level of carbon dioxide in the atmosphere was never more than 300 parts per million at any point in the past 400,000 years—until now, when it’s at 400 parts per million.
That excess of carbon dioxide is accelerating the greenhouse effect, trapping more and more heat on Earth. That much is almost certain: National Geographic reports that, in 2013, 98 percent of all scientists agreed that was the case.
Great, but what is climate change?
Now, you might be thinking, So what if the Earth warms up 1.6 degrees—that’s not much at all! But it turns out that those 1.6 degrees make a big difference.
Global warming ends up changing a lot of things about the Earth’s climate, which is why we also talk about “climate change.” As the Environmental Protection Agency (EPA) wrote in 2017, “Climate change refers to any significant change in the measures of climate lasting for an extended period of time. In other words, climate change includes major changes in temperature, precipitation, or wind patterns, among other effects, that occur over several decades or longer.”
There are a few big changes in particular that should be understood.
1. Rising sea levels
As the planet warms up, the sea levels begin to rise as well. National Geographic explains that it’s due to a number of factors. In particular, the higher temperatures are melting glaciers, polar ice caps, and other ice sheets, which adds more water to the oceans. On top of that, water expands when it heats up, adding to the problem.
“When sea levels rise rapidly, as they have been doing,” the magazine continued, “even a small increase can have devastating effects on coastal habitats.” That puts hundreds of millions of people around the planet who live on the coasts at risk. You can see which people at Climate Central’s interactive map or reports by region from the EPA.
2. Stronger storms and other dangers
Rising temperatures and sea levels also increase the intensity and frequency of deadly weather phenomena.
For instance, human-caused climate change is leading to stronger hurricanes, according to the Union of Concerned Scientists (UCS). The Geophysical Fluid Dynamics Laboratory, which works with the National Oceanic and Atmospheric Administration (NOAA), estimates that human-caused climate change will increase the intensity of storms by between 2 and 11 percent on average, leading to more Category 4 and 5 hurricanes, which are incredibly dangerous, as the recent hurricanes in Puerto Rico, Florida, and Texas show.
On top of that, global warming is leading to worse wildfires, more heat waves, and increasing flooding, according to UCS. All told, National Geographic reports that “the number of climate-related disasters has tripled since 1980.”
3. Ocean acidification
Another especially important, but lesser-known impact of carbon dioxide emissions is ocean acidification.
As the NOAA explains, the oceans actually absorbs about 25 percent of the carbon dioxide released into the atmosphere. But that doesn’t mean it goes away; it means that the ocean’s waters have chemicals in then, making them more acidic—30 percent more acidic than they were before the Industrial Revolution, according to the NOAA.
That increase in acidity has terrible effects for ocean life. In March of last year, the New York Times reported that large sections of Australia’s famous and beautiful Great Barrier Reef have died. Other sea life, including shellfish like oysters, are also being threatened by acidification, according to the NOAA. If that continues, it could threaten the livelihoods of the one billion people who depend on seafood for their meals or jobs.
What can we do?
That is the question. And it’s not one with a clear answer.
Scientists, politicians, economists, biologists, activists, and so, so many others are working every day to figure out what we can do to limit carbon emissions, reduce global warming, and ensure a healthy, livable planet. But it’s a big, complicated problem.
The hard truth, according to Princeton University’s Carbon Mitigation Institute, is that we’re going to have to change a lot of things. They argue that the only solution is to “find energy technologies that emit little to no carbon” in order to reduce global warming, while also developing “the capacity for carbon storage” to remove some of the carbon already causing the greenhouse effect.
To do so, they recommend adopting several different strategies, including things like increasing fuel efficiency in cars, switching to other fuel types, adding solar and wind energy, stopping deforestation, and more.
None of those are easy. But if scientists are right, it’s the only way forward.
Leave a Reply