ABSTRACT

190Observational networks for drought monitoring are maintained by national meteorological services, hydrological services, departments of agriculture, departments for welfare and economic upliftment, NGOs, etc. They have a large number of objectives to provide service to a variety of users. These networks keep on recording observations on weather, hydrology, agriculture, and socioeconomic conditions of the population irrespective of a drought. The number of parameters, quality of observations, instrumentation, and observing techniques are nonuniform in countries and within countries. Thus, the historical records are not of uniform quality and length.

Satellites are being used to remotely sense Earth. From 1960 onward, the tremendous improvement in remote sensing technology has resulted in more parameters becoming available at improved resolution. In 1960s, the resolution of the satellite images was limited to identifying the objects of size 10 × 10 km, while WorldView-4, launched on November 11, 2016, will identify the objects of size 31 × 31 cm, thus facilitating improved drought monitoring.

This chapter is written to describe observing networks as sources of information generation and how these information are collected. Drought monitoring requires a portion of data observed by these networks. Drought monitoring at global scale and some important drought monitoring systems are described.