Deeper and Cheaper Analysis in the Cloud
Massive cloud computing resources and analytical tools for working with big datasets make it possible extract new information from imagery
The combination of new sensors, deeper archives, and better computing ability make it possible to draw sophisticated information from satellite imagery. In many cases, development partners can now process imagery in the cloud without having to invest in expensive hardware and software.
Insights from invisible light
Many satellites capture light in wavelengths that are outside the range of human vision, such as infrared or ultraviolet light, that can help to understand the surface characteristics of the reflecting substances. Different objects reflect these light frequencies in different ways, and common satellite analysis techniques combine human-visible and invisible images (called “spectral bands”) to characterize their subjects. For example, spectral bands covering frequencies in the middle-infrared wavelength regions are responsive to moisture content in vegetation, forest canopy and soil, while near-infrared wavelength regions tend to emphasize vegetation health and— at a coarser scale— overall biomass.
Taken together, the spectral response of each band creates a unique signature, referred to as its spectral curve. The information it communicates can help to separate different types of land cover or derive information about the conditions within a single type of land cover.