Microwave Remote Sensing

Abstract

Persistent cloud cover, especially within the tropics, offers limited clear views of the Earth’s surface from space. This presents a major impediment to the application of optical remote sensing discussed in Chap. 8 in providing global remote sensing coverage. Moreover, other than thermal sensors, most other optical imaging technologies best operate during day time when there is sufficient sunlight. The microwave region of the EM spectrum represents a principal atmospheric window that can be employed to overcome the above limitations in optical remote sensing. For instance, in view of their much longer wavelengths and contrary to optical sensors, microwaves can easily penetrate through vegetation canopies and even dry soils. In addition, microwave systems offer the user more choice and control over the properties of the incident microwave energy to be applied. Furthermore, they can be operated round the clock even under rainy or poor visibility conditions.