Topic 1c Part 2: Using Satellites to Measure The Cryosphere
We’ve established the important role that the cryosphere plays in our climate and why we need to use satellites to measure the cryosphere - but how do we measure it?
In this lecture, Professor Andrew Shepherd explains how we measure Earth’s ice from space using satellites.
Earth observation (often shortened to EO) allows us to monitor the cryosphere over a large scale. EO missions, such as ESA’s Copernicus mission, are gathering huge amounts of data - which allow us to continually monitor the cryosphere.
Each satellite has different types of instruments and and sensors that measure the cryosphere in different ways.
For example, Cryosat-2 can track changes in the thickness of ice. It has a resolution of about 1.3 centimeters. The satellite uses the SIRAL (SAR Interferometer Radar Altimeter) instrument. The SIRAL uses radar to determine and monitor the spacecraft’s altitude in order to measure the elevation of the ice.
Another satellite that measures the cryosphere is the ICESat-2. Onboard ICESat-2 is the ATLAS (Advanced Topographic Laser Altimeter System) which measures ice sheet elevation and sea ice thickness. It shoots out 10,000 laser pulses per second, then takes measurements every 28 inches along the satellite’s path.
Follow the link in the optional further reading to access ESA's Climate Change Initiative, which is a project set up to realise the full potential of the long-term global EO archives that ESA has gathered from satellites over the last 30 years.
Featured Educator:
- Professor Andrew Shepherd
(This video was filmed remotely during COVID-19 lockdown conditions)
CRYOSAT-2
ICESAT-2
Course topics
The core videos of this course are labelled as topic videos.
We have also provided a range of optional further reading, links, and additional resources to help consolidate your learning. Here is a summary of what is available:
Topic links and resources
In each topic, once you have watched the video and read the accompanying text, you will find the following information:
- Optional Further Reading: These are external links to further reading.
- Featured Images and Animations: Below the text on each video page, you’ll find the featured images and featured animations.
- Interactives: On the 'Interactives' tab on relevent topic pages, you will find a satellite tracking application showing the current location of the satellites, a data viewer from the ESA WEkEO platform, as well as a data viewer, specially created for this course, allowing you to explore a selection of data relevant to the themes and topics in this course. (Please note that due to maintenance, the data viewer is currently unavailable).
Quizzes and comments
- Quizzes: At the end of each week there will be a quizz consisting of around five questions. These will help you consolidate your understanding of new topics, but are not scored. The feedback given with each answer also will also provide you with important information.
Weekly interactive exercises
At the end of each week, we have included a guided exercise, using interactive apps available on other websites, to help you become more familiar with looking at and working with EO datasets. You will be guided through the process of searching for, comparing and drawing conclusions from data relevant to some of the topics covered in that week.
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A list of the EO satellite missions mentioned throughout the course, with information and links.
