Arid lands are vulnerable to many of the same kinds of weather-related disasters that are experienced in temperate climates, but there are some that can be much more severe. One type of disaster may be generally referred to as severe weather, which encompasses dust storms and flash floods. Another type of disaster, desertification, is related to the vulnerability of arid land vegetation and substrates to human- and climate-induced perturbations. This chapter describes the physical processes associated with each of these types of disasters and provides examples of each.

Introduction

Desert weather and climate, and associated disasters, have historically been primarily of academic concern to all but the few local residents, even though some broader long-term interest has existed because of military activities, the exploitation of the desert's great natural resources, agricultural reclamation through irrigation, and the perception of some regional climatic trends toward desertification. However, more recently, population growth in arid areas has often surpassed that in more temperate zones, the attractions being unpolluted air, abundant sunshine, beautiful landscapes, and endless open space. In North America, for example, population growth in urban areas of the Sonoran Desert in the second half of the twentieth century occurred much more rapidly than in New England and in the Midwest.