Basic science: understanding numbers
Basic science: understanding numbers

Start this free course now. Just create an account and sign in. Enrol and complete the course for a free statement of participation or digital badge if available.

2.3.1 Volume of the Greenland ice sheet

Previously, you were given the area for the Greenland ice sheet. To work out the volume, you will need to have an idea of how thick it is. We don’t know exactly how thick it is at every location, but you can work out a fairly good estimate.

You can work out an upper limit for the volume by knowing that it is about 3,000 m, or 3 km, thick at its thickest, so multiplying the area (1,710,000 km2) by the thickness (3 km) gives a maximum volume of 5,130,000 km3for the ice on Greenland.

But the ice is thinner in places, so what is the lower limit? At the edges of the ice sheet, the thickness of the ice tails off to a few tens of metres. If you assume a minimum thickness of 50 metres, or 0.05 km, you get a value of 1,710,000 multiplied by 0.05, or 85,500 km3 as the lowest estimate of the volume of the ice. This is still a lot of ice!

You can get a much better idea of the volume of ice, however, by using the average thickness. This has been worked out, from borehole drilling and radar measurements, to be about 1,500 m, or 1.5 km.

Activity 2.1 Calculating the volume of the Greenland ice sheet

Timing: Allow about 15 minutes

If you multiply the area of 1,710,000 km2 by 1.5 km, you get a value of 2,565,000 km3 for the volume of the ice on Greenland. Use the internet to look up official estimates of the volume of ice on Greenland. How do you think we did using the simple area and average thickness?

In the next section, you will look at why ice floats on water, when you discuss density.

Take your learning further

Making the decision to study can be a big step, which is why you'll want a trusted University. The Open University has 50 years’ experience delivering flexible learning and 170,000 students are studying with us right now. Take a look at all Open University courses.

If you are new to University-level study, we offer two introductory routes to our qualifications. You could either choose to start with an Access module, or a module which allows you to count your previous learning towards an Open University qualification. Read our guide on Where to take your learning next for more information.

Not ready for formal University study? Then browse over 1000 free courses on OpenLearn and sign up to our newsletter to hear about new free courses as they are released.

Every year, thousands of students decide to study with The Open University. With over 120 qualifications, we’ve got the right course for you.

Request an Open University prospectus371