Suchergebnisse

In the semi-arid region of the Sahel, climate change is already affecting the farming systems and these impacts are expected to heighten in the near to mid-century. Given the complexities and conflicting drivers at play and the foreseeable negative consequences on the livelihoods of the majority of farmers, it is worthwhile designing relevant adaptation packages that will alleviate these effects. In this study, we envision to assess the implications of implementing two adaptation packages within the context of three West African farming systems specifically located in Ghana (Navrongo), Mali (Koutiala) and Senegal (Nioro). The first adaptation package is composed of heat and drought tolerant species along with an economic and policy level intervention through the delivery of subsidies to acquire improved varieties. The second pack builds on the first but adds a fertilizer component (splitting and timing to account for extreme events) and a policy variable in the form of index-based insurance adoption. The design process included interactions with a diverse set of stakeholders. The outcomes of these adaptation options on current and future agricultural systems will shed light on the projected adoption rates of climate adapted-systems and show how these various adaptations affect the impacts of climate change, keeping congruence with the relevant representative agricultural pathways. (Texte intégral)

To reduce the risks of climate change, governments agreed in the Paris Agreement to limit global temperature rise to less than 2.0 °C above pre-industrial levels, with the ambition to keep warming to 1.5 °C. Charting appropriate mitigation responses requires information on the costs of mitigating versus associated damages for the two levels of warming. In this assessment, a critical consideration is the impact on crop yields and yield variability in regions currently challenged by food insecurity. The current study assessed impacts of 1.5 °C versus 2.0 °C on yields of maize, pearl millet and sorghum in the West African Sudan Savanna using two crop models that were calibrated with common varieties from experiments in the region with management reflecting a range of typical sowing windows. As sustainable intensification is promoted in the region for improving food security, simulations were conducted for both current fertilizer use and for an intensification case (fertility not limiting). With current fertilizer use, results indicated 2% units higher losses for maize and sorghum with 2.0 °C compared to 1.5 °C warming, with no change in millet yields for either scenario. In the intensification case, yield losses due to climate change were larger than with current fertilizer levels. However, despite the larger losses, yields were always two to three times higher with intensification, irrespective of the warming scenario. Though yield variability increased with intensification, there was no interaction with warming scenario. Risk and market analysis are needed to extend these results to understand implications for food security.