Farmers used to be able to rely on predictable weather patterns. We enjoyed mild temperatures throughout the year, regularly punctuated by winter cold and summer heat.
Over the last centuries, many factors produced environmental changes that has warmed our planet considerably and lengthened hot days.
“Change in climate is mainly attributed to the unabated increase in greenhouse gases, including fluorinated gases, carbon dioxide, methane, and nitrous oxide, which bring changes in rain patterns, temperature and negative effects on water and land resources.” (MDPI, 2017)
The earth’s carbon dioxide concentration was below 280 ppm (parts per million) before 1960 or the preindustrial age. It rose to 382 ppm in 2006 and is now 409.5 ppm this year. The considered safe level is 350 ppm.
“Over the past 10 years, the extremely hot days have become more numerous than the cooler than average days….[A]lmost 150 times more common than they were just 30 years ago.” (An Inconvenient Sequel Truth to Power, Al Gore, 2017)
Increasing hot days affect many countries differently.
“Climate change is considered to be a global phenomenon; however, its impacts are more widely felt in the developing countries, due to their greater vulnerabilities and lesser ability to mitigate the effects of climate change.” (MDPI)
“Disaggregation by region shows that adverse impacts appear particularly strong for South Asia and Southeast Asia, and smaller in the other developing regions.” (Institute of Physics)
But the world’s food growers suffer the most when extreme heat lowers water supply and rainfall and causes droughts and wildfires.
“[C]limate change can pose threats to agriculture and food security by changing the spatial and temporal distribution of rainfall, water availability, land capital, biodiversity, and terrestrial resources.” (MDPI)
As temperatures rise, crop yields fall globally. (PNAS, 2017)
Climate change has reduced crop yield growth by 1-2% per decade says the IPCC, a United Nations panel on climate change.
Major crops
If carbon emissions are not reduced quickly, global crop yields for the coming years will decrease as follows: corn by 7.4%; wheat by 6%; rice by 3.2%; and soybeans by 3.1%. (PNAS)
By 2100 major crop production is predicted to decline dramatically: wheat and barley by 17 to 33%; soybean 40%; and maize by almost 50%.
Maize, rice, and wheat make up 51% of the world’s calorie intake (United Nations Food and Agriculture Organization or UN FAO) and 94% of global cereal consumption.
The climate’s adverse impact is stronger for oilseeds and rice than for wheat. (IOP Science)
US, China, and Brazil are the world’s leading producers of maize. Also called corn, 38% of US production is used to feed livestock, 15% is exported, and the rest is used in food and products like fuel, cereal, sweeteners, and oil.
Recent heat waves also destroyed 60% of corn in Serbia and over 50% in the Czech Republic.
As temperatures rise, 2060 corn yield in Texas, US is predicted to drop by 40%. Other Texas crops affected are cotton, rice, and hay. Texas is also the US top producer of cotton and the US is the world’s third producer of cotton.
World production of another cereal, barley, is lower due to dry weather in Morocco and Turkey, with significant production declines in the European Union. (UN FAO)
In Korea, UN FAO issued an alert last July that if the severe dry spell is not offset by rainfall, the cereal production will decrease to unprecedented levels.
Produce
The US Produce Alliance’s latest report this week said that oranges, onions, and carrots remain in short supply; the prices of Roma and round tomatoes will go up; while the following vegetables suffered from high heat: iceberg lettuce, broccoli, mushroom, parsley, spinach, and green beans.
Last September, an unrelenting dryness in southern Queensland and New South Wales in Australia significantly reduced yields for winter grains and oilseeds. (World Agricultural Weather Highlights)
An Australian farmer said that leafy greens suffer heat stress when temperatures rise above 35 degrees Celsius (95 degrees Fahrenheit). It destroys and wilts crops, and causes heat damage and fringe burn. No one wants to buy heat damaged greens.
The United Kingdom suffered a very long dry spell last April with just 41% rainfall after the driest fall and winter season since 1996. This led to a vegetable shortage and some rationing of lettuce, eggplant, tomatoes, courgettes, asparagus, and potatoes. Other sensitive fruits were also affected: apple, pear, berry and vine fruit crops.
Lucifer, Europe’s crippling heatwave last August dried up the mediterranean region’s olive production in the world’s top olive growers—Spain, Italy, and Greece.
Italy’s olive production fell by 50% this year due to muggy weather which attracted fruit flies and bacterial growth. Last spring’s heat waves in Greece cut output by 25%. While floods ruined the harvest in Andalusia, Spain’s main growing region.
Olives in Italy and Spain also suffered in the 2014 drought which produced the world’s lowest crops since 2000. For the last three years, there has been an olive oil shortage which hiked up prices by at least 10%. Some European restaurants were forced to raise prices or close.
Lucifer also dried up half of the world’s grape growers—Italy, France, and Spain. A study by NASA and Harvard found that since the1600s, climate change pushed harvests drastically sooner in France and Switzerland since 1985. The hotter temperatures force growers to pick the ripe grapes sooner before they dry out, but this means a lower yield and less time for the flavors to fully develop.
Other studies say that wine regions in Europe can soon become too hot to grow grapes due to droughts.
2017 has the worst global grape harvest since 1982. Italy, the world’s biggest producer, will decrease volumes by 21%, and by 15% for France and Spain. The wine world total will fall by 8%, especially for chianti and prosecco.
But all is not lost, there is still a surplus of wine in storage. However, California’s wildfires this month may contribute to a future shortage of this surplus. Much depends on upcoming harvests.
India’s annual temperature has been rising by 0.7 degrees Celsius (33.26 degrees Fahrenheit) which can hurt its winter crops, or those affected by changes in temperature: wheat, barley, oats, chickpea/gram, linseed, and mustard.
India depends 65% on rainfall to water its monsoon crops, which are affected by changes in rainfall: rice, maize, sorghum, cereal, pulses, soybean, groundnut, and cotton. India is the world’s second producer of rice and wheat, and a leading producer of spices, tea, fruits, vegetables, sugarcane, cotton, and oilseeds.
However, India’s 59% rainfall, April heat wave, and drought will decrease this year’s production of coconut, soybean, cotton, oilseeds, pomegranate, and vegetables. It’s presently hurt by an agricultural crisis.
The world’s agricultural food supply remains relatively stable as long as growers from unaffected areas of the earth can make up the shortage in heat-affected countries.
“Global rice production in 2017 is now forecast at an all-time high of 503 million tonnes, up 0.5 percent from the revised estimate for 2016 and 0.5 million tonnes above July expectations. The revision is primarily the result of small upward adjustments to production forecasts for India, the Philippines and Thailand, more than compensating for downward revisions made for China and the Democratic People’s Republic of Korea.” (UN FAO, Quarterly Global Report, September 2017)