What is the effect of climate change on agriculture and food production?
Climate change might not be all bad for the agriculture sector. Really?
Yes. Moderate warming and higher CO2 in the atmosphere may even help some plants to grow faster. You will surely remember your high school botany where you learnt that plants need CO2 and sunlight during photosynthesis. Which means more CO2 and a bit more warmth might make some plants grow faster. Increased CO2 and global warming do suddenly seem to be a good idea for agriculture, doesn’t it?
But wait. This is not the end of the story.
While you heard the pluses, here come the minuses.
Global warming is likely to result in more floods and drought. And an increase in temperature might not be good for all plants. For example, if temperature exceeds a crop’s optimal level, yields could decrease. Similarly, if sufficient water and nutrients are not available owing to floods or droughts, yield increases may be reduced or reversed.
Agriculture in tropical regions will likely be the hardest hit by climate change. Higher global temperatures will make it more difficult for farmers to work in the heat of the day, leading to less food production. The problem with food production decreasing near the equator is that almost all of the human population growth that’s predicted for the next 50 years will occur in the tropics.
Areas that experience increasing temperatures due to climate change will also likely see an increase in crop pests. Currently, pests are responsible for 25 to 40 percent of all crop loss, and as climate change continues, these pests will be able to expand their reach. Many weeds, pests, and fungi thrive under warmer temperatures, wetter climates, and increased CO2 levels. This could cause new problems for farmers’ crops previously unexposed to these species.
The quality of crops might also suffer owing to greenhouse gases and global warming. For instance, elevated CO2 levels have been associated with reduced protein and nitrogen content in alfalfa and soybean plants, resulting in a loss of quality.
While there could be some positives for agriculture from global warming, it is expected that climate change could have many more adverse effects on agriculture, both quantitatively and qualitatively. The net effect is likely to be highly negative.
Effect of climate change and global warming on food production
Apart from its adverse effects on agriculture in general, how will climate change and global warming affect food production in specific?
Isolating the influence of climatic change from all the other trends on food production is difficult, but one recent Stanford University study found that increases in global production of maize and wheat since 1980 would have been about 5% higher were it not for climate change.
As mentioned earlier, in the short term, there could be beneficial effects for food production from climate change! All else being equal, rising carbon dioxide concentrations – the main driver of climate change – could increase production of some crops, such as rice, soybean and wheat. However, the changing climate would affect the length and quality of the growing season and farmers could experience increasing damage to their crops, caused by a rising intensity of droughts, flooding or fires. In the medium and long run, the net effect is likely to be negative.
Wheat is the first big staple crop to be affected by climate change, because it is sensitive to heat and is grown around the world, from Pakistan to Russia to Canada. Projections suggest that wheat yields could drop 2% a decade owing to climate change.
Another danger is for the world’s fisheries, which provide an important source of protein for at least half the world’s population. Warming surface waters in the oceans, rivers and lakes, as well as sea level rise and melting ice, will adversely affect many fish species.
Even where yields do increase in the short term owing to increased CO2 levels, research shows that when certain foods are grown at high levels of atmospheric carbon dioxide, they lose some of their nutritional value. Recall the case of alfalfa and soybeans mentioned earlier.
Similar to the case of agriculture, while it could have positive effects for select regions/crops, it is expected that climate change and global warming could have severe adverse qualitative and quantitative effects on food production, both plant and animal based food.
