An investigation of the potential impact of climatic change on maize production in Central Angola

Abstract

Maize production is sensitive to weather and hence directly affected by climate change that is difficult to be controlled by the farmer, compromising yield and food security, especially for producers located in Huambo and Bié in Central Angola. An investigation of the potential impact of climatic change on maize production in Central Angola was carried out using future (2050s as average of 2041 to 2060) and (2070s as average of 2061 to 2080) climate scenarios from a Global Climate Model (GCM) named HadGEM2-ES and AquaCrop simulation Model of rain-fed maize growth and yield. The study used historic climatic data (monthly and annual mean, maximum and minimum air temperature and monthly and annual rainfall), as well as downscaled model from Global Climate Model using the same parameters except monthly and annual mean temperature and rainfall. Historic data (observed) from the period 1961 to 2011 was provided by the Meteorological Service Institute of Angola (named, INAMET) and comprised Bié and Huambo provinces. Climate characterisation showed slight decline in rainfall for Huambo province over all the period (1961-2011), while for Bié province no marked variation was shown. Maize analyses showed that there was no relationship of temperature and rainfall with maize yield. The comparison between observed (historical) reference period and modelled current climate showed an agreement between both climates for maximum temperature (Tmax) and minimum temperature (Tmin) for Huambo province, while Bié showed a close relationship on rainfall but marked gap on temperature. The comparison between the observed and 2050s showed marked difference of increased temperature, especially for Bié province, while for Huambo the observed and 2050s showed less difference. Comparison between observed and 2070s showed a marked gap between the two climates for Tmax for Bié. As for Huambo both climates are shown closer. Climate change had no marked effect on maize yield for both provinces, they performed closer values. Long cultivar showed effect on yield over the short and normal cultivar for both provinces. The last planting date of 25-November showed effect on maize yield over 07-October and 25-October planting date for the two provinces.