In just 40 years, the world's population doubled. Between 1959 and 1999, we grew
from 3 billion to 6 billion people, and we've added nearly another 2 billion since then.
So, how do we make sure there's enough water, electricity, food, and other resources for
everyone when the population grows that fast? This is one of the biggest questions facing
Earth scientists today, and we're going to see if we can help out with finding some solutions.
By the end of this lesson, you'll be able to identify examples of renewable and non-renewable
resources and explain what makes a resource either renewable or non-renewable. Let's get started!
Whether we're charging our phones or drinking a glass of water, we're all constantly using
resources. A resource is a material used to support the needs of living things, like the
need for food or shelter. Humans are constantly using resources to generate energy, grow food,
manufacture goods, build houses, create medicine, and more. So, how do we make sure we have enough
resources for all 8 billion people on Earth? Won't we run out at some point? Well, I have good news.
There are some resources that, no, we really won't run out of. We call these renewable resources.
A renewable resource is a resource that is naturally replenished over a short period of
time. In other words, it's a resource we aren't likely to run out of because it's replaced
faster than we can use it. A great example of a renewable resource is sunlight. In just one hour,
our planet receives more energy from the Sun than everyone on Earth uses in an entire year,
and the Sun isn't going to run out of light anytime soon! We can use our endless supply
of sunlight to generate energy, which is why solar panels are becoming more and more common.
Wind is another renewable resource. As long as the Sun is causing global
patterns of heating and cooling, we'll have plenty of wind. People have used this
renewable resource for centuries to push sailboats and turn windmills. Nowadays,
we use wind turbines to harness the force of wind and turn it into energy.
Plants are another important renewable resource. We use the wood from trees for building houses and
making paper and grow tons of different plants for food. Even the plants that we don't directly use
are still helpful, since they produce the oxygen we breathe. New plants grow and naturally replace
the ones we use over time, and we often help this process along by farming too. However, trees and
plants can become non-renewable if we harvest them faster than they're able to grow back.
We have pretty stable access to renewable resources like sunlight, wind,
and plants. However, non-renewable resources take an extremely long time to replenish. They're used
up much faster than they're replaced, meaning it's very possible we'll run out eventually.
Fossil fuels, like oil and coal, are some of the non-renewable resources
we use the most. These fuels are used to generate electricity, to power cars,
and even to make plastic. Most people use these resources every single day!
However, our planet won't be getting more fossil fuels anytime soon. They take millions of years to
form, and we use a lot of them. We're on track to run out of fossil fuels in under 200 years.
Metals like gold and copper are also non-renewable resources because it takes such a long time for
them to be replenished by the rock cycle. We use these metals for all sorts of things,
from jewelry to the conductors in our cell phones. We mine thousands of pounds of both
of these resources every year, and at this rate, we'll run out of them before long too.
This one might sound surprising, but sand is also a non-renewable resource. Sand takes a
long time to form, since it's made of rocks and minerals that are broken apart during the
rock cycle. We use tons of sand in construction jobs to make materials like concrete. In fact,
it's the second-most-used resource on our planet,
and we're using it up much faster than the rock cycle can replace it.
Most resources on our planet are either renewable or non-renewable, depending on how long it takes
our supply to replenish. However, there are a few that Earth scientists can't quite agree on. Two
of the resources in this in-between category are water and soil. Why do you think these resources
are so hard to classify? Pause the video here and record your thinking in your guided notes.
Let's look at a resource we all use every day: water. Thanks to the water cycle,
this precious resource is constantly replenished as it moves through the Earth system. But as you
might remember, very little of the water on Earth is usable fresh water. While the
water cycle does replenish this small amount of fresh water, we use water faster than it's being
replaced. That's why water conservation is so important. We definitely don't want to run out!
Soil is even harder to categorize than water. If we carefully manage how we use soil when growing
crops, it can be replaced faster than we use it, making it renewable. But these careful practices
aren't always followed, and soil forms extremely slowly. It can take over 500 years for a single
inch of soil to form, making it easy to see how it can be considered non-renewable too.
Its status as a renewable or non-renewable resource often
just depends on where the soil is and whether or not it's being cared for.
So, what do you think the solution is? What should we do to make sure
we have enough resources for everyone on Earth, especially as our population continues to grow?
Pause the video here and record your thoughts in your guided notes.
Most Earth scientists think that one of the most important things we can do to ensure we
have plenty of food, energy, medicine, and everything else we need is to try to use
renewable resources whenever possible. In our next lesson, we'll take a closer look at the steps we
can take to carefully manage our planet's resources and what can happen if we don't.
In the meantime, let's recap what we learned today. Now you know that renewable resources
are replenished faster than we use them, while non-renewable resources take an extremely long
time to replenish. You also know that using resources too quickly may eventually cause us to
run out of some of them, including resources we'd usually think of as renewable. Be sure to complete
the practice questions and extension activities that go with this lesson to learn more about our
planet's resources. And always remember, in Earth science, as in life, you rock! See you next time.