If you're 30, see what the Arctic ice cap was doing when you went to high school.
If you're 30 years old, you've seen a good amount of change in your lifetime. Over the years you've gone from child to teenager to real adult. You've worked your way through the trials and tribulations of first steps, first crushes, and first jobs. You went to school, got jobs, and grew up. It's the start of an immense and grand story.
But you're not the only thing changing in this story. As you've grown, the background has changed too. Sometimes it's obvious — like moving to a new house or a new city.
But is it possible that larger things changed too?
If you're 30, you started the first grade around 1991 or so.
Let's go way back — the first real day of school. New teachers, new kids. Homework, for the first time ever. I remember someone informing me that there were 11 more grades to go and being baffled that anything could possibly take that long!
Meanwhile, the world spun on. Plants grew and died with the seasons, storms came and and went, and up in the Arctic, the ice grew and shifted, as always.
You were a high school freshman in 1999, or so.
Eight years later, you were probably starting high school. You weren't the hyperactive kid anymore; you were more stable. More collected. More cool (maybe).
Meanwhile, exciting things were happening in the world. "Star Wars: Episode I," "The Matrix," and "Family Guy" all premiered that year. People were Y2K-proofing their computers. And everyone was drawing that weird S-thing on their notebooks.
And the Arctic still went through its annual cycle of freeze and thaw.
This is an animation created by the National Oceanic and Atmosphere Administration, by the way. The colors in the GIFs show how old the ice is: The whiter the ice is, the older it is.
And ice, like people, tends to get stronger and more resilient as it matures. It's more likely to stick around through tough times. At first there seemed to be a lot of old ice. But something's changing...
If you went to college, you were probably the class of 2007.
Bob Barker bids farewell to "The Price Is Right," but Don Draper steps into the zeitgeist as the wildly-popular "Mad Men" premieres. The final "Harry Potter" book comes out.
As for you, this was a year of caps and gowns and new jobs. By now you were into your 20s — officially an adult — someone with real responsibility and experience. Someone who things can start to count on to stick around.
But the same can't be said for the North Pole.
Did you spot the pattern? Look close - the white part's starting to disappear. The old ice is going away.
But by then the old ice had practically disappeared.
That means the entire ice pack is weaker, more fragile, and more likely to melt in the summer. In 2012, for example, the summer extent of the ice was only about half the 1979-2000 average.
It's as if someone took a population of strong, resilient adults and replaced them with first graders.
What will the world be like by the time the next generation turns 30?
By the time the kids born in 2011 turn 30, the Arctic could be largely ice-free during the summer.
This could have huge implications for the planet. Melting sea ice could change weather patterns thousands of miles away. Ocean currents could change too. And all the people and animals — like polar bears — who depend on the ice would be in serious trouble.
But we can still do something about the underlying cause. By using less fossil fuel and investing in green energy, we can help slow down climate change and, hopefully, help retain as much of that mature ice as we can.
And it starts with us knowing what's going on in the great white north. Let's spread the word.
Watch the full animation below: