Thermal characterization of clouds using simple bispectral infrared imaging systems

摘要

Since its inception, the objective of the Infrared Laboratory-LIR has been the design and development of simple and low-cost IR systems for the resolution of specific problems in real time. This methodology can be used in a multitude of technological applications: energy, environmental, medical, etc. In this work, we focus on the characterization of clouds using a simple bispectral system in the thermal IR region. The study of clouds in the IR, region is a problem studied since the use of the first on-board measurement systems. The imaging systems have become more sophisticated, giving rise to multispectral instruments capable of providing a huge amount of information on clouds with great accuracy. These systems arc generally large in size, weight and cost. However, there are many situations where the goal is not to obtain comprehensive information about the clouds, but only ancillary information. In these situations, the low-cost approach of LIR is ideal for designing simple cloud characterization systems. In this work, a methodology is presented to determine the emissivity and temperature of the clouds based on the brightness temperature measured from space by a bi-spectral camera in the 10 and 12 microns bands. In addition, we provide quantitative information on the capabilities of the methodology according to the type of clouds based on real data provided by MODIS instrument.