As I write this, 97% of climate scientists think that climate change is happening now and that the reason it is happening is because of people. “97% of climate scientists” does not mean 97% of the climate scientists in Washington, DC, or 97% of the climate scientists in the United States. It means 97% of all the climate scientists in all the countries around the world (including the U.S).
Why would pretty much all the world’s scientists think such a thing? Mainly because they have been collecting decades and decades of evidence that show this is happening.
Some of the evidence is that Earth’s average annual temperature has been rising. Scientists have been measuring and recording temperatures around the Earth for about 135 years. At the end of each year, they look at all those temperature records for the year and figure out the average temperature for the entire planet. This means we now have about 135 years of average temperature records. When you graph these average temperatures, it looks like this (except, not necessarily with a sunset in the background):
As you look at this graph from left to right, you are seeing the average temperatures for each year from 1885 to 2015. If the climate was not changing, the average temperatures would change from year to year (because weather is never perfectly consistent), but the center of the jagged line would stay pretty much in the same place. That is not what you see on the actual graph, though. The jagged line takes a dramatic turn upwards as you look to the right, meaning the average temperature keeps getting higher as you approach our present time, meaning the Earth is getting warmer, meaning our climate is changing.
Even if scientists hadn’t been recording temperatures around the world for 135 years, there is other evidence they have observed that show our planet is getting warmer. Here are a few examples:
Glacier National Park is running out of glaciers.
Glacier National Park did not get its name because the first European guy to discover it was named Zebulon Glacier. It has that name because it is a national park that once was full of glaciers (over 150 glaciers were in the park when it was founded in 1910). Glacier National Park is now down to only 25 glaciers and those glaciers that are left are all a lot smaller than they used to be.
Here’s how just one of Glacier National Park’s glaciers has changed over the last century:
Why are the glaciers disappearing? Because Glacier National Park has kept getting warmer since 1910.
If the warming continues (which, unfortunately, it will) the glaciers in Glacier National Park will all be gone in your lifetime, and this national park will have to be called The National Park Formerly Known as Glacier.
You can learn more about how much glaciers have melted in Glacier National Park by going here.
Frozen mammoths in Siberia are thawing out.
First you should know that the thawed mammoths are already dead, so they won't be attacking your town anytime soon. Mammoths used to live in Siberia until they started going extinct around 10,000 years ago. The remains of many of these dead animals have been preserved by the Siberian permafrost ever since then. “Permafrost” is the name for places where the ground remains frozen for years at a time. You find permafrost in the tundra near the polar regions as well as on the top of many tall mountains, or at least you used to. The permafrost in Siberia (and many other places) is no longer “perma.” Much of it is melting into mud. This has led to a Siberia Tusk Rush. The newly unfrozen permafrost makes it much easier to find and collect pieces of dead mammoths. This makes Siberia Tusk Rushers excited because you can sell mammoth tusks for the ivory in them and make lots of money.
Why are frozen mammoths thawing out? Because it is much warmer in Siberia than it used to be.
You can learn more about the melting permafrost and the Siberia Tusk Rush by going here.
People can now sail across the Arctic Ocean.
That is a big deal because, until just five years ago, there was too much ice to allow anyone to travel by boat through the Arctic Ocean. This did not stop people from trying. For hundreds of years European sailors looked for a “Northwest Passage” through the Arctic Ocean, but they weren’t successful because of the massive amounts of ice in their way. Many of them died trying.
It is normal for some of the polar ice to melt in the warmer summer months and then come back in the cold winter, but it never used to melt enough in the summertime to allow anyone to sail north of Alaska, Canada, or Russia without large and dangerous chunks of ice stopping them.
It’s a different story now as this video shows...
The ice cap has melted so much that in the summer of 2016, for the first time ever, a cruise ship was able to sail through the Arctic Ocean. So an ocean journey that once killed people can now be done leisurely while overeating at a nonstop buffet.
Why is the Arctic polar ice cap melting? Because it is warmer in the Arctic Ocean than it used to be.
You can learn more about the melting Arctic ice cap and the way it opening up new shipping routes by going here.
Some Pacific islands are disappearing underwater.
As of just recently, five of the Solomon Islands in the Pacific Ocean are now completely below the ocean surface. These weren’t huge islands. The biggest one now underwater was about the size of nine football fields, but still.
The Solomon Islands are not the only ones disappearing below the ocean. The island nation of Kiribati in the Pacific is worried enough about rising sea level that it is currently buying land in another country so its people have a place to go once their islands homes are underwater.
Why are islands in the Pacific starting to disappear? Because the Pacific Ocean is warmer than it used to be. Let me explain.
All things expand when they get warmer, so as the ocean gets warmer, the water in it keeps spreading out. Since the only way ocean water can spread out is by going up, this results in rising sea level. Sea level is also rising because as the air gets warmer around the world, it melts glaciers (like, the ones in Glacier National Park) and the water from those melted glaciers often makes it to the ocean.
Scientists have been measuring sea level using satellites since at least 1870 and it has risen over ten inches so far. If it continues to rise (and unfortunately it will) islands like this one will be in big trouble:
You can learn more about the disappearing Solomon Islands by going here.
Antarctica is turning green.
Simple plants called mosses can briefly grow along the northern edges of Antarctica during the warmer summer months. This only happens on less than 1% of Antarctica surface, though. The other 99%-plus of Antarctica remains covered in ice all year long. Well, at least until recently. Scientists are finding moss growing in more places and quicker than it ever use to.
Why is Antarctica turning greener? Because it’s warmer there than it used to be there.
You can learn more about the greening of Antarctica by going here.
The Great Barrier Reef is bleaching.
“Bleaching” does not mean the Great Barrier Reef is dyeing its hair blonde. That would be awesome. It means the reef is dying, period (“dying” without the “e” in the middle).
The reason coral reefs are bleaching has to do with the fact that corals live together with algae (corals and algae have what scientists call a “symbiotic relationship”). Corals want to be roommates with algae because algae can make their own food from sunlight through photosynthesis. The corals mooch off the algae and that way the corals get enough food to eat too. In return, the corals gives the algae a safe place to live.
This arrangement changes when the temperatures get too high. When it's hot, the corals kick out their algae roommates. Scientists are not 100% sure why this happens. It may be because the algae never do the dishes, but a more reasonable theory is because the heat changes the algae's ability to share food with the corals and, since they can't help each other anymore, they go their separate ways. When this happens, the corals not only lose their main food source, but also their color (all the colors in corals come from their algae roommates), thus the name "bleaching" because the reef suddenly turns white.
Without the algae, the corals eventually start dying, which takes away food and shelter from all the other animals who hang around the reef, so all those animals have to move out too. You end up with a reef that looks something like this:
When a healthy coral reef should look something like this:
If things cool off in a month or so, the corals can recover, and the reef springs back to life. If it stays unusually warm for too long, though, the corals starve to death and the entire reef stops working as a habitat for other animals, who all have to move out and hopefully find another place where they can survive.
This is what is happening in the Great Barrier Reef north of Australia. The Great Barrier Reef is a coral reef that is 1,400 miles long, which is about the same distance as my house in Rochester, New York to Miami, Florida. It is so big that astronauts can see it from space (the reef, not my house).
Unfortunately, the 2016-2017 summer (remember, Australia is in the southern Hemisphere, so they have summer at the same time people in North America and Europe have winter) is the second year in a row that the Great Barrier Reef has experienced massive bleaching, and the scientists who study it are seeing that much of it is not coming back.
Why is the Great Barrier Reef bleaching now? Because the ocean north of Australia is much warmer than it used to be.
You can learn more about the bleaching of the Great Barrier Reef here.
I could actually keep going and list other examples that show evidence for how the world is getting warmer, like how spring flowers keep opening up earlier each year and they’re now out of whack with the pollinators who migrate to feed off them. Or how invasive species from warm places, like fire ants, keep spreading farther north. Or how pikas are disappearing because mountain tops where they live are now too warm for pikas to survive there. And so on. But I'm already pushing the limits of how long anyone will read a blog post, so I will move on.
If the only story I had to share was about the glaciers in Glacier National Park melting, then the only thing we could say is something weird is happening in Glacier National Park. But if you look at all the places I just mentioned when they are displayed on a map:
There’s something weird happening across the entire planet.
And all we talked about was how temperature is changing. Other types of weather events are regularly becoming more extreme, which is also an example of climate change. More areas around the world are experiencing droughts and/or intense storms than ever before.
This is because heat is energy, so the warmer the atmosphere is, the more energy it has, and the more energy there is bouncing around in the atmosphere, the crazier the weather gets.
So it is definitely a fact that climate change is happening in our lifetimes.
But that still leaves the question: Why do scientists think people are causing climate change? Climate change has happened many times in the past when we weren’t even around. Why is now different?
I’ll write about that in my next post.
So far I don't have any books specifically about climate change, but the subjects of all of them are connected to climate change is some way (except maybe my sports gear book). You can learn more about all my books here.
Online References and Resources:
The Atlantic. "Earth's Oceans Are Steadily Warming."
The Atlantic. "When Will The North Pole Melt?" video.
BBC News. "Five Pacific islands disappear as sea levels rise."
Bloomberg. "Apocalypse Tourism? Cruising the Melting Arctic Ocean."
The Conversation. "Great Barrier Reef bleaching event: what happens next?"
EOS. "How Does Changing Climate Bring More Extreme Events?"
The Guardian. "American pika vanishing from western US as 'habitat lost to climate change'."
The Guardian. ""Arctic ice melt 'already affecting weather patterns where you live right now'."
The Guardian. "Besieged by the rising tides of climate change, Kiribati buys land in Fiji."
The Guardian. "Climate change is disrupting flower pollination, research shows."
The Guardian. "Global warming is causing more extreme storms."
LiveScience. "New Clues Emerge On How Corals Bleach."
NASA. "Global Climate Change: Global Temperature."
NASA. "Global Climate Change: Sea Level."
National Geographic. "These Maps Show the Epic Quest for a Northwest Passage."
National Geographic. "Tracking Mammoths."
The New York Times. "As Arctic Ice Vanishes, New Shipping Routes Open."
The New York Times. "California Drought Is Made Worse by Global Warming, Scientists Say."
The New York Times. "How 2016 Became Earth’s Hottest Year on Record."
The New York Times. "It’s Not Your Imagination. Summers Are Getting Hotter."
The New York Times. "Large Sections of Australia’s Great Reef Are Now Dead, Scientists Find."
The New York Times. "Mapping 50 Years of Melting Ice in Glacier National Park."
The New York Times. "A Remote Pacific Nation, Threatened by Rising Seas."
NOAA. "How does climate change affect coral reefs?."
NOAA. "U.S. Climate Extremes Index (CEI): Graph."
RadioFreeEurope. "The Mammoth Pirates."
Science Friday. "Antarctica Is Getting Greener."
Smithsonian. "Does Climate Change Cause Extreme Weather Events"
Smithsonian. "How Climate Change is Helping Invasive Species Take Over."
USA Today. "The Arctic, Antarctic poles just set a terrifying new record for low levels of sea ice."
USGS. "Retreat of Glaciers in Glacier National Park."
The Washington Post. "Thanks to global warming, Antarctica is beginning to turn green."
The Washington Post. "Why some of the Solomon Islands have disappeared."
YaleEnvironment360. "A Close-Up Look at the Catastrophic Bleaching of the Great Barrier Reef."
Chasing Coral, a documentary you can watch on Netflix.
Photos and Images:
Click the photos and images used above to find their sources.