Since SAR instruments don’t depend on the Sun’s energy to collect surface data, SAR satellites can operate just as well during the day or night. Additionally, SAR signals can penetrate through clouds to “see” the covered surface underneath, allowing satellites to have a full view of the Earth’s surface regardless of atmospheric or lighting conditions. SAR can also “see” through other types of cover such as smoke, vegetation, snow, or sand, depending on the satellite’s designated operating band (which indicates the sensor’s associated frequency and wavelength). SAR bands are helpful in categorizing the penetration strength and thus the potential applications of a satellite, such as Germany’s TanDEM-X (low-penetration X-band), Canada’s RCM (moderate-penetration C-band), and Japan’s ALOS-2 (high-penetration L-band).

A common feature among all SAR satellites is their more detailed collection of data about the Earth’s surface, which makes SAR imagery a highly valuable tool for scientists and policymakers to better understand our changing environment.

Given the increased threats of environmental phenomena to national and global security, SAR can provide additional information to assess and respond to climate change, ecosystem loss, natural disasters, and more.