Climate Change Has Already Cut Food Production Drastically
Advances in technology and better crops have boosted agricultural productivity across most of the world, but there are dark clouds looming, with climate change already cutting productivity 21 percent worldwide, and sending it backwards in some places. Image Credit: Edwin Remsberg, University of Maryland
Among the many frightening consequences of a warmer world, one of the worst is what it will do to agricultural production. A new study finds that isn't just something for the future – we are already growing a fifth less food than we would if the world had maintained 1960s conditions. Technological progress has hidden this until now raising overall yields. However, as warming accelerates, agricultural scientists will have to work harder to keep up.Even in a pandemic world population is growing by tens of millions of people annually, and that won't stop any time soon. Better distribution of food can help avoid famines to an extent, but avoiding a hungry future almost certainly means producing more food. Climate change makes that harder, but no one has been sure how much.
Professor Robert Chambers of the University of Maryland has sought to answer that question. In Nature Climate Change he concludes there has been a 21 percent reduction in global food productivity since 1961 as a result of the changing climate, including more droughts in some places and floods in others.“Agricultural productivity measurement hasn't historically incorporated weather data, but we want to see the trends for these inputs that are out of the farmer's control," Chambers said in a statement. Previous studies of the influence of global heating on agriculture have focused on cereals as the largest source of calories, but Chambers and co-authors used the value of crops to include all foods we grow."We used the model in this paper to estimate what total factor productivity patterns would have looked like in the absence of climate change." Chambers added. "Our study suggests climate and weather-related factors have already had a large impact on agricultural productivity,"
The introduction of hybrid crops like dwarf wheat and more widespread use of fertilizers and machinery have made agriculture much more productive over the period Chambers studied, saving us from predicted calamities. Nevertheless, the changing climate has eaten up seven years of productivity growth.Missing out on those potential gains has made food more expensive, leaving some to starve entirely. It's also forced farmers to expand the areas they sow, destroying ecosystems that will never come back and sending species extinct.Chambers previously conducted a similar analysis for the United States, where he found climate effects have so far been modest compared to the advances science and engineering have brought. Expanding the assessment to the whole world showed brought worse news. Africa, Latin America, and the Caribbean, the places that can least afford losses in food production, lost 26-34 percent of their productivity as a result of climate effects. A small number of nations, mostly in central Africa, have seen total agricultural productivity fall over the last 60 years. Russia and Canada have experienced climate change-induced rises in agricultural productivity, but they're almost alone."Some people think about climate change as a distant problem, something that should concern primarily future generations. But this overlooks the fact that humans have already changed the climate," said first author Dr Ariel Ortiz-Bobea.
Climate Change and Pollution Threaten Future Food Supplies
There have been studies implicating air pollution for causing lower crop yields. There have been studies accusing climate change of the same thing. However, scientists have often overlooked the damaging potential of these two factors working in concert. A new study led by Colette Heald of MIT has revealed that when pollution and climate change are factored together, four of the largest crops in the world will be severely affected by 2050, which threatens global food security. The team’s findings were published in the journal Nature Climate Change. On a global level, half of the calories consumed each day come from corn, wheat, rice, and soy. Unfortunately, all of them are threatened by the challenges of a warming climate and ozone air pollution, though not in the same way. Corn has difficulty growing in the heat, and wheat is more sensitive to poor air quality. Soybeans get hit especially hard, because heat increases ozone production from the reactions in sunlight which create harmful compounds and damage the plant.There are a lot of factors that go into projecting what the global population will be by 2050, but between population growth, decreased infant mortality, increased life expectancy, and dietary changes, the world will need to produce about 50% more food than it currently does. Unfortunately, Heald’s team found that global crop yields are predicted to decrease.
Without altering any other factors, increased temperatures will likely decrease crop yield by about 10%. When the team adjusted the amount of ozone, the outcomes were exacerbated or improved. Ozone pollution causes plant leaves to become discolored or speckled, but those symptoms can also be caused by various fungal infections or nutrient deficiencies. Though climate change isn’t going to help any of the four major crops, air quality seems to make the biggest difference in projected outcome.The team ran the numbers under a few different scenarios regarding temperature and air quality. Under more dire circumstances, crops may be reduced by 15%. Scenarios that involve cleaner air put that figure at 9%. This is even worse for regions that are already plagued by hunger. Worst case scenario, malnourishment in developing countries would increase from 18 to 27%. However, even the most optimistic air quality figures would still increase that figure to about 22%. There are ways to make this impeding food demand a little easier to manage. About one third of all food in the world is wasted, according to the UN’s Food and Agriculture Organization. If this waste were eliminated, there would be enough food to feed an additional 2 billion people, without changing anything else. Even if food waste was completely eliminated, that is not enough to meet the projected food demands. The agricultural community will need to address the need for decreased emissions and better crop planning based on region in order to mitigate the impending global food shortage.
