Climate Change 101 with Bill Nye | National Geographic

[Music] We hear it so much that it feels like a buzzword, but it is far from it. Climate change is a real and serious issue. But isn't the climate always changing? What exactly is climate changing? Why should we care?

Well, the Earth's climate has changed throughout history. Most of these slight changes are caused by small variations in the Earth's orbit. But climate change, as we know it today, is characterized by an abrupt increase in the Earth's temperature. It is estimated to have gotten 1.2 to 1.4 degrees Fahrenheit warmer in just the last century. Ten out of the last thirteen years were the warmest on record. Ninety-seven percent of climate scientists agree that this new tendency is not caused by the variations of the Earth's orbit, but rather very likely caused by human activities. That means you and me.

Since the Industrial Revolution, we have come a long way. Humans built airplanes, faster cars, developed remarkable technology, and learned how the natural resources around us can be used for our benefit. Although this has led to many wonderful inventions and advancements like the device you're using to watch this video, or the ability to take a plane halfway around the world, it also means we've increased our consumption of natural resources and in turn released a lot of greenhouse gases into the atmosphere.

Now, greenhouse gases occur naturally, but in excess can be dangerous to our planet. Modern human activities have increased the release of non-naturally occurring greenhouse gases because we have stepped up our demand for burning fossil fuels. The composition of greenhouse gases traps heat radiated from the Sun. The more heat they trap, the warmer our planet gets. And as our planet gets warmer, we begin to feel the effects.

One of climate change's biggest victims are oceans. Oceans regulate the Earth's temperature and provide fifty percent of the Earth's oxygen. Climate change has increased the global temperature of the oceans by more than 3° Fahrenheit since 1969. Although a warmer ocean might seem inviting to a beachgoer, it actually has devastating consequences for supporting life at sea. One of those consequences is ocean acidification, a direct effect of increased dissolved CO2.

Since the late 18th century, ocean surface acidification has increased by thirty percent. A higher acid content means calcifying species like oysters, clams, and shallow water corals are at risk, putting the entire ocean food web at risk. This is bad news for the one billion people relying on the ocean as their primary source of protein.

Climate change has also caused the sea level to rise. Just in the last century, sea levels have risen 6.7 inches, but the rate in the last decade has nearly doubled. Sea levels have risen because as the ocean gets warmer, it swells. On top of that, glaciers and ice sheets are melting. Antarctica lost thirty-six cubic miles of ice between 2002 and 2005, and since 1994, each year on average, the Earth has lost four hundred billion tons from its glaciers. That's like an ice cube seven and a half kilometers on a side or four miles on a side melting and flowing into the sea.

When all that ice melts, it fills up our oceans, and just like filling up a bathtub, the shores can't hold all that water, and coastal regions get flooded. Troubling signs of climate change are increased extreme weather events. Natural disasters like floods, tornadoes, and deadly heat waves are more obvious to humans because of their immediate impact and their sharing of the images in the media.

Climate change, as we know it today, is a change in our Earth's overall temperature with massive and permanent ramifications. Although its consequences can be planet-threatening, scientists still believe there are things we can do on a personal level to help.

Recycle and reuse things. Walk or use public transportation to get to work. Turn off your electronics when you're not using them. Eat less meat. While you're at it, eat more locally grown vegetables and foods. And last but not least, spread your knowledge and concerns about climate change with others.

When it comes to climate change, the main takeaway is that it's real, and although we are part of the cause, we can also be part of the solution. [Music]