INTRODUCTION

Weather and climate have a profound influence on ecosystems. The climate of a region can act as a resource for an ecosystem as a whole, influencing the phenology of an area (Chapter 3), and as a determinant of food supply for primates, which can in turn affect reproduction, ranging and social interaction. While climate provides the background conditions, the real-time monitoring of local weather can provide a much more direct link to primate field studies at any given time. For example, daily temperature cycles can influence activity patterns (Chapter 17).

Local weather information can be straightforward to collect and the value of local observations at field study sites (as opposed to extrapolation of conditions from the nearest ‘official’ weather station, which may be far away) often offsets any deficiencies in observation technique. Weather conditions also vary within a field study area as a result of the microclimate (e.g. Rosenberg et al., 1983; Geiger et al., 1995) and, as a result, local conditions can differ significantly from larger scale climatological surveys such as Buckle (1996) and McGregor & Nieuwolt (1998).

This chapter describes the types of local weather information that can be collected; shows how weather can vary over both space and time, enabling the interpretation of point observations in the context of wider conditions; and finally shows how local atmospheric conditions can easily be measured during fieldwork using different types of portable instrumentation.