Ghana and neighboring Côte d’Ivoire produces around 60% of the world production of cocoa (Theobroma cacao L.), one of the world’s major commodities. In 2010 cocoa accounted for
8.2% of Ghana’s GDP and 30% of total export earnings, creating employment for about 6 million people and a livelihood for 700.000 cocoa farming families (GAIN, 2012, Asante-Poku & Angelucci, 2013),thus representing an important pillar in both rural and urban poverty alleviation and development of the economy of Ghana at large. An increasing global demand for cocoa and a production gap in the global market suggest a further growth potential for cocoa and thus a continued significant role for farmers and businesses in Ghana. Climate models predict temperature increases from 1-2.5 °C for Ghana by 2050. Although precipitation patterns are more uncertain, it seems that future climates will be highly variable and more prone to drought and temperature extremes. According to Läderach et al (2013), areas suitable for cocoa cultivation in Ghana will decrease due to a temperature mediated increase in evapotranspiration not compensated by increasing rainfall, i.e. a decrease in water availability rather than by the direct effect of increasing air temperature. This will increase the risk of drought to which cocoa is very susceptible. In their study, Läderach et al (2013) simulated impacts of CC limited to the definition of the suitable area for cocoa based on a generic model that does not take into account the effects of CC on cocoa yield, as it is not specific to cocoa ecophysiology and does not integrate the effects that CC will have on pests and diseases. Furthermore, these simulations 2 on potential cocoa growing areas do not take into account the adaptation strategies that farmers will be developing or adopting to cope with CC. Furthermore, literature reviews reveal a surprising lack of knowledge of the response of different cocoa systems to extreme climatic events making predictions uncertain (Zuidema et al., 2005). In addition there is little if any knowledge on adaptive measures in the light of climate change, especially among cocoa communities in Ghana. Against this background, there is an urgent need to develop climate smart cocoa systems, substantiated by improved knowledge on cocoa eco-physiology, analyses of field data, farmers’ strategies and the surrounding institutional set up. It is increasingly recognized that trees in cocoa systems improve crop production, provide timber and fuel wood, fruits and other products as well as valuable ecosystem services such as carbon sequestration, soil fertility enhancement, and biodiversity conservation (Vaast & Somarriba, 2014). Consequently they can contribute greatly to enhancing food, nutrition and income security of smallholders that produce over 80% of world cocoa. From recent studies in Central America and Indonesia, there is increasing evidence that trees, through microclimatic amelioration, also enhance the resilience of cocoa systems to climate change which is threatening the livelihood of rural cocoa communities globally. Nevertheless, the cocoa sector is mainly advocating an increase in cocoa production through the intensification of cocoa systems mainly via improved germplasm and use of agrochemicals in full sun monoculture, and hence removal of shade trees which decreases smallholders’ ability to cope with price volatility of cocoa, pests and diseases outbreaks and climate change. This is also the case in Ghana, where cocoa farms have primarily been managed under low shade or no shade (Gockowski & Sonwa, 2011), as agricultural extension services in Ghana have promoted intensive systems in full sun to maximize short-term yields
(Asare, 2005).
Today, cocoa yields are declining because of low soil fertility and pest and disease pressures, posing severe challenges to the cocoa sector, from farmers to processors (Ruf, 2011; Tscharntke et al., 2011). Farmers rarely have the financial means to purchase the substantial amounts of fertilizers, fungicides and pesticides needed for enhancing production (Ahenkorah et al. 1987, Ruf & Zadi, 1998), and the notion that full-sun and intensive cocoa systems is superior to other management systems has been questioned. Sun-grown cocoa trees age more rapidly than shaded trees, necessitating a more frequent renewal of the plantation (Jagoret et al., 2011; Gyau et al., 2014). Furthermore, recent research has demonstrated that on-farm yields are often larger in shaded than in non-shaded systems (Asare et al., forthcoming). It seems likely that the traditional agroforests are buffering environments, leading to closer-to-optimum conditions for cocoa, especially under conditions of climate stress, while simultaneously working to increase the carbon storage that can help counter climate change.
Furthermore, the need for specific policies addressing CC adaptation in a local context depends on how important the impacts of CC are expected to be and whether farmers can adapt to induced changes in their environment (Burke & Emerick, 2013). The bulk of the empirical research on CC impacts on agriculture has focused on field crop agriculture in developed economies with little or no studies on perennial crop such as cocoa in a developing country like Ghana.