Topic 2e - Looking at land

In this video Dr Mathias Disney explains some of the challenges of observing the land surface from space, and uses mapped measurements of reflected solar radiation made by the Landsat series of satellites to explore certain changes in forest cover that have occurred between 2000 and 2012. Dr Kirsten Barrett then explains how, by combining data from different EO instruments beyond just those that measure reflected solar radiation, we can try to expand further our knowledge of the Earth’s vegetation.

Observing the land surface from Earth observation satellites allows us to assess key changes in this component of the Earth system, over a wide range of spatial and temporal scales. The land surface is highly heterogeneous, and many areas are changing quite dramatically due to current human activity, for example in tropical forests where land is being cleared for agriculture and logging is extracting commercially valuable trees. Such changes in forest cover have also historically taken place extensively across many temperate regions, (for example in Europe), but well before EO satellites were available to assess these changes. Studying Earth’s terrestrial vegetation, and the changes currently occurring in this vital part of the Earth system, is now a key task of satellite Earth observation.

The vast, sometimes remote, and often highly heterogeneous areas of the land surface we need to observe are often difficult to study from the ground alone. Satellites provide us with global coverage, but also a highly spatially detailed view, allowing us to collect data repetitively over even the most remote land areas on the planet. We can use different EO measurement approaches to assess a wide range of parameters of the land surface system repetitively, enabling us to identify and quantify changes in parameters such as albedo, net primary productivity and canopy height, and allowing us to build a much more precise understanding of the Earth system as a whole.

Featured Educators:

  • Dr Mathias Disney

Other Featured Experts:

  • Dr Kirsten Barrett

View featured satellites on the satellite tracking app

Don’t forget you can download the video, transcript and take any quizzes available with the links on the right.