Drought Early Warning and Forecasting - Chapter 1 - Droughts, governance, disasters, and response systems

This chapter places droughts in historic context. Since the beginning of history, periodic droughts have had large impacts on many societies. These impacts have been especially severe in agricultural civilizations that depend heavily on precipitation for bountiful harvests. Historically, these harvests provided the critical resources that enabled the advancement of ancient humanity, allowing our ancestors to build cities, pursue trades, and develop sophisticated religious and cultural systems. Droughts have long played a major disruptive role in history, threatening the stability of human society. Here, we briefly review the relationship between civilizations and drought, stressing the link between agriculture and drought impacts. We then introduce the topic of modern drought prediction, highlighting the seminal contributions of Sir Gilbert Walker, and describing climate mechanisms associated with the Southern Oscillation and the Indo-Pacific Warm Pool. To conclude, we will provide a summary description of the phases of early warning.