telerilevamento

Remote sensing, or telerilevamento in Portuguese and Italian, is the science and technology of obtaining information about objects or areas from a distance by measuring reflected or emitted radiation. Sensors mounted on satellites, aircraft, drones, or ground-based platforms collect data across the electromagnetic spectrum, from visible light to infrared and microwave. Remote sensing data can be passive, detecting natural energy from the sun, or active, emitting signals such as radar or lidar and measuring the return signal.

Data products vary in spectral, spatial, and radiometric resolution. Spectral resolution determines the number and width of bands; spatial resolution is the size of the smallest discernible object on the ground; radiometric resolution relates to the sensitivity to light intensity. Typical workflows include data acquisition, radiometric and geometric corrections, projection to a standard coordinate system, and analysis such as classification, change detection, or surface temperature estimation. Results are often integrated with geographic information systems (GIS) for mapping and decision making.

Common platforms include Landsat, Sentinel-2, SPOT, and MODIS, offering decades of data with growing open access. Applications span land cover and land use mapping, agriculture, forestry, urban planning, water resource management, disaster response, climate research, and environmental monitoring. Limitations include atmospheric interference, mixed pixels at coarse resolutions, and data volume. Ethical and legal considerations cover privacy and sovereignty in high-resolution sensing. Advances in sensor technology, hyperspectral imaging, lidar, microwave radiometry, and automated analysis continue to expand telerilevamento’s capabilities and cost-effectiveness.