Satellite radar interferometry effective for mapping crops

Traditionally, optical, or ‘camera-like’, satellite images are used to map different crops from space, but a recent study shows that Copernicus Sentinel-1 radar data along with interferometric processing can make crop-type mapping even better. This, in turn, will help improve crop-yield forecasts, production statistics, drought and storm damage assessments, and more.

The Sentinel-1 mission comprises two identical satellites, each carrying an advanced radar instrument to provide a day-and-night, all-weather supply of images of Earth’s surface. These images are used for numerous applications such as monitoring sea ice and floods, as well as shifts in the land surface or ice surface through the process of interferometry (InSAR) – which is where images of the same place from consecutive satellite passes are compared to reveal differences that occurred between image acquisitions.

Going further, a paper, published inthe IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, describes how Sentinel-1 InSAR can go beyond the measurement of terrain displacement.

The animation shows coherence maps gathered over the whole year. The presence of white and black rectangles in the cultivation area is according to the absence or presence of crops, and how they change along the year.

Juan M. Lopez-Sanchez, also from the University of Alicante, added, “Some crop types which were poorly classified by either intensity or coherence are better distinguished by the combination of both types of polarisation data types. In other words, both sources of information are indeed complementary.”

Crop-type mapping using satellite imagery plays a key role in Europe’s Common Agricultural Policy, in which ‘checks by monitoring’ are being established routinely to reduce field work and the associated bureaucracy. Moreover, it also helps monitor potential threats to ecosystems if new crops are introduced close to protected areas.

During the development of the SInCohMap project, all the possible combinations of images acquired in one year were computed and analysed.

The Sentinel-1 mission comprises two identical satellites, each carrying an advanced radar instrument to provide a day-and-night, all-weather supply of images of Earth’s surface. These images are used for numerous applications such as monitoring sea ice and floods, as well as shifts in the land surface or ice surface through the process of interferometry (InSAR) – which is where images of the same place from consecutive satellite passes are compared to reveal differences that occurred between image acquisitions.

Going further, a paper, published inthe IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, describes how Sentinel-1 InSAR can go beyond the measurement of terrain displacement.

The animation shows coherence maps gathered over the whole year. The presence of white and black rectangles in the cultivation area is according to the absence or presence of crops, and how they change along the year.

Juan M. Lopez-Sanchez, also from the University of Alicante, added, “Some crop types which were poorly classified by either intensity or coherence are better distinguished by the combination of both types of polarisation data types. In other words, both sources of information are indeed complementary.”

Crop-type mapping using satellite imagery plays a key role in Europe’s Common Agricultural Policy, in which ‘checks by monitoring’ are being established routinely to reduce field work and the associated bureaucracy. Moreover, it also helps monitor potential threats to ecosystems if new crops are introduced close to protected areas.

During the development of the SInCohMap project, all the possible combinations of images acquired in one year were computed and analysed.

The Sentinel-1 mission comprises two identical satellites, each carrying an advanced radar instrument to provide a day-and-night, all-weather supply of images of Earth’s surface. These images are used for numerous applications such as monitoring sea ice and floods, as well as shifts in the land surface or ice surface through the process of interferometry (InSAR) – which is where images of the same place from consecutive satellite passes are compared to reveal differences that occurred between image acquisitions.

Going further, a paper, published inthe IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, describes how Sentinel-1 InSAR can go beyond the measurement of terrain displacement.

Satellite radar interferometry effective for mapping crops

blijf op de hoogte