Maxine Betteridge-Moes | April 28, 2019
It’s the middle of the dry season in northern Ghana and Mariam Mohammed is tending to her vegetable garden. Mrs. Mohammed lives in Bihinaayili, just outside the regional capital, Tamale. Her garden is lush and green, thanks to runoff water from a reservoir that provides river water for year-round irrigation. In this arid climate, the community is lucky to have access to a watershed that helps them grow crops.
Mrs. Mohammed is getting ready to prepare her land for the upcoming planting season. She watches the clouds forming in the sky and feels the temperature rising, telling her that the rainy season is approaching. Over the years, the dry season has become increasingly hotter and drier. Rainfall is more erratic. Farmers are becoming aware of the changing weather pattern, but have limited information on effective strategies for adapting to the changes.
The Potsdam Institute for Climate Impact Research and the German Development Authority recently completed a study in Ghana on the impact of climate change. Among other things, it studied past, present, and projected climatic conditions, water availability, and crop production. The study also recommended adaptation strategies for farmers.
The study found that average temperatures will increase considerably over the next few decades and that precipitation levels will vary across the country, with rainfall slightly increasing in the north and decreasing in the south until mid-century. This will have wide-ranging effects on staple crops like maize, groundnuts, sorghum, and cassava.
Lisa Murken is one of the lead authors of the study. She says it can be difficult to understand climate change because the climate does not always change in a linear or consistent fashion across geographic areas. For example, some regions will experience more flooding and others prolonged droughts.
She adds, “It’s important for smallholder farmers to know there will be an increase in extreme [weather] events.”
According to the study, northern Ghana will experience the highest temperature increase—up to 2.5 degrees Celsius above current temperatures by 2050. Combined with variable rainfall, this will have a significant impact on which crops are suitable for different areas.
The report predicts that maize will be the crop hardest hit by climate change. Over one-third of the land currently suitable for maize will become marginal for growing the crop by 2050. This shift will happen mainly in the Northern, Upper West, and parts of Ashanti regions. Given the economic significance of maize in Ghana and in many other African countries, this could have severe consequences for food security.
According to the study, there are a number of strategies that farmers can use to adapt to the changing climate. These include post-harvest activities, irrigation, harvesting rainwater, using improved crop varieties, and crop insurance. The report states that, while some strategies are easier to adopt than others, small changes can make a big difference in crop yields and resiliency—and that a combination of strategies is most effective.
For example, according to the study, using PICS storage bags is an effective post-harvest management strategy that is accessible and affordable for small-scale farmers. PICS bags feature two layers of polyethylene inside a woven sack, and can seal harvested grain from pests and contaminants for over a year after harvest.
Irrigation systems are especially useful during the dry season. But they can be costly and labour-intensive to implement on a large scale. The report states that rainwater harvesting is a cost-efficient and time-saving alternative, particularly for women, since they are usually in charge of fetching water.
The study says that farmers are being encouraged to plant improved crop varieties that are more tolerant of heat and drought and can produce higher yields. It reports that a number of improved crop varieties already exist or are being developed, but that only about 20 per cent of farmers in Ghana are using improved seeds, compared to an estimated 25 per cent across sub-Saharan Africa. Challenges to greater adoption include access to high quality seeds and a weak public extension system.
Finally, the report advises farmers to purchase crop insurance wherever possible in order to protect against droughts, floods, and other potential damage. These kinds of weather events are likely to increase in frequency with climate change. The study states that carefully designed insurance schemes can be affordable and sustainable for small-scale farmers. For now, access to credit, education, and lack of experience with insurance remain barriers to many small-scale farmers’ ability to purchase it and interest in doing so.
The inevitability of climate change and the potential for severe impacts on small-scale farmers means that it is vital for farmers to be well-informed and prepared. Ms. Murken and her colleagues are encouraging the government of Ghana to implement crop insurance schemes, improve extension services, and take advantage of indigenous knowledge wherever possible to ensure that farmers are using local knowledge in their efforts to adapt to a changing climate.
She says: “We’re hoping that [the government] will bring the findings of the study to their extension service, which will in turn sensitize farmers on climate change and [the] expected climate impacts for farmers.”