Dr Moses Amweelo
In Namibia, agriculture is one of the most important sectors. Around 70% of the country’s population depends directly or indirectly on agriculture for their income and livelihood – mostly in the subsistence sector.
However, the country’s arid climate and geographic conditions do not favour farming and the crop variety is rather limited. Major crops include maize, millet and sorghum. Agricultural production is under threat due to climate change in food-insecure regions, especially in Africa and Asian countries.
Various climate-driven extremes; drought, heat waves, erratic and intense rainfall patterns, storms, floods and emerging insect pests have adversely affected the livelihood of the farmers.
Future climatic predictions showed a significant increase in temperature and erratic rainfall with higher intensity while variability exists in climatic patterns for climate extremes prediction.
Global food security relies on both sufficient food production and food access, and is defined as a state when: “all people, at all times, have physical and economic access to sufficient, safe and nutritious food to meet their dietary needs and food preferences for an active and healthy life” (FAO, 1996). The principal barrier to food security is currently food access.
Sufficient food is produced globally to feed the current world population, yet more than 10% are undernourished. Climate change is likely to contribute substantially to food insecurity in the future, by increasing food prices, and reducing food production.
Food may become more expensive as climate change mitigation efforts increase energy prices. Water required for food production may become more scarce due to increased crop water use and drought.
Competition for land may increase as certain areas become climatically unsuitable for production.
In addition, extreme weather events, associated with climate change may cause sudden reductions in agricultural productivity, leading to rapid price increases.
These rising prices forced growing numbers of local people into poverty, providing a sobering demonstration of how the influence of climate change can result in food insecurity.
The consensus of the Intergovernmental Panel for Climate Change (IPCC) is that substantial climate change has already occurred since the 1950s, and that it’s likely the global mean surface air temperature will increase by 0.4 to 2.6 degrees Celsius in the second half of this century (depending on future greenhouse gas emissions). Agriculture, and the wider food production system, is already a major source of greenhouse gas emissions.
Future intensification of agriculture to compensate for reduced production (partly caused by climate change) alongside an increasing demand for animal products, could further increase these emissions. It’s estimated that the demand for livestock products will grow by +70% between 2005 and 2050.
While gradual increases in temperature and carbon dioxide may result in more favourable conditions that could increase the yields of some crops, in some regions, these potential yield increases are likely to be restricted by extreme events, particularly extreme heat and drought, during crop flowering.
Crop production is projected to decrease in many areas during the 21st century because of climatic change. Heat waves (periods of extreme high temperature) are likely to become more frequent in the future and represent a major challenge for agriculture. Heat waves can cause heat stress in both animals and plants and have a negative impact on food production.
Extreme periods of high temperature are particularly harmful to crop production if they occur when the plants are flowering; if this single, critical stage is disrupted, there may be no seeds at all. In animals, heat stress can result in lower productivity and fertility, and it can also have negative effects on the immune system, making them more prone to certain diseases.
Projected changes in climate are not limited to increases in temperature and heat waves; large changes in rainfall patterns are also expected to occur. While some regions are likely to suffer from more droughts in the future, other regions are expected to face the opposing issues of torrential rains and increased flooding.
In coastal areas, rising sea levels may result in a complete loss of agricultural land. Warmer climates may also lead to more problems from pests and diseases, and shifts in the geographical distribution of certain pests.
For example, insects that serve as a vector for disease transmission are likely to migrate further pole-ward in the future, where livestock have so far not been exposed to the diseases. Agriculture is a particularly important sector in Africa, contributing towards livelihoods and economies across the continent.
On average, agriculture in Sub-Saharan Africa contributes 15% of the total GDP.
Africa’s geography makes it particularly vulnerable to climate change, and 70% of the population relies on rain-fed agriculture for their livelihoods. Smallholder farms account for 80% of cultivated lands in Sub-Saharan Africa.
The IPCC in 2007 projected that climate variability and change would severely compromise agricultural productivity and access to food. This projection was assigned “high confidence”.
Cropping systems, livestock and fisheries will be at greater risk of pests and diseases as a result of future climate change. The impacts of climate change on agricultural production in Africa will have serious implications for food security and livelihoods.
Between 2014 and 2018, Africa had the highest levels of food insecurity in the world. Agriculture contributes towards climate change through direct greenhouse gas emissions and by the conversion of non-agricultural land such as forests into agricultural land. Emissions of nitrous oxide and methane make up over half of total greenhouse gas emissions from agriculture.
*Dr Moses Amweelo is a former minister of works, transport and communication. He earned a doctorate in technical science, industrial engineering and management from the International Transport Academy (St. Petersburg, Russia).