Chapter 2 Literature review 2.1 Introduction Climate change is currently generally regarded as a major global issue that is especially acute in developing countries. This study focuses on the impacts of climate change and variability on smallholder farmers, their vulnerability and coping strategies on a micro-scale in a developing country. In order to get a comprehensive picture of these issues, this chapter reviews literature on climate change and vulnerability. It begins by defining climate change and analyzing global climate change in general and its impacts on local smallholder farmer’s livelihoods in a developing country such as Zimbabwe. Lastly the chapter also assesses the measures of adaptation which smallholder farmers can use to increase their coping capacity and resilience to climate change and variability. 2.2 Definition of climate related phenomena 2.2.1 Climate change Climate change refers to shifts in the mean state of the climate or in its variability, persisting for an extended period of decades or longer (Ziervogel and Zermoglio, 2009). It is the change in average atmospheric behavior, and change in the patterns of variation around this behavior (Rumbach and Kudva, 2011). The Intergovernmental Panel on Climate Change (IPCC) declared that climate change is unequivocal as evidenced by observed changes in several global and regional climatic indicators (IPCC, 2007). At the country level, climate change refers to observable changes and permutations (undefined geographic variations) of temperature, rainfall and extreme climate events and their single or collective impacts on various agricultural production (Lasco, et al., 2009). Climate change is largely attributed to anthropogenic factors which have caused some mo… … middle of paper … … and feed grains (Nyong, 2008). Higher temperatures can the physiological development of crops such as causing increased respirations, shorter periods of seed formation and reduced biomass production which all result in hastened maturation and reduced crop yields (Adejuwon, 2004). Global warming and drought have affected the change in the incidence and distribution of pests and pathogens which presents challenges for crop management and animal rearing. Moisture and temperature are important elements of climate which determine the occurrence and localization of pests and diseases (Adejuwon, 2004). This is because pests and diseases vectors thrive well in optimum conditions of high temperature and abundant water supply. In this way climate change and global warming has extended the range of distribution of some pests and diseases worsening the plight of farmers.