This USGS activity leads students to an understanding of what remote sensing means and how researchers use it to study changes to the Earth’s surface, such as deforestation. 

In this activity, you will use an inexpensive spectrophotometer* to test how light at different visible wavelengths (blue, green, red) is transmitted, or absorbed, through four different colored water samples.

Check out how Dr. James Smith, Research Scientist at Biospheric Sciences Branch at NASA Goddard Space Flight Center researches changes in the Biosphere using remote sensing techniques.