“We already have trouble feeding the world and this additional impact on crop yields will impact the world’s poorest…”
Few of you will have escaped the heatwave that seems to have enveloped most of the northern hemisphere. Soaring temperatures exceeding 46°C have been recorded in Alvega, Portugal, while seventeen of eighteen of the countries regions experienced temperatures above 45°C. This follows recent headlines reporting wildfires in California and Greece while 40°C heatwaves have caused deaths in Japan. Events like these, once considered freakish in nature are now becoming increasingly frequent.
Rising temperatures are characteristic of the changing global climate and the warnings of the implications that this change could have on production and agriculture are no longer just hypothesis by a reality for many. Changes to regional and global temperature will continue to have damaging effects on agricultural systems at both national and global levels and by extension the bio-based economy. The evolution of weather patterns once considered rare to common only serves to highlight a need for agricultural BAU (Business-As-Usual) models to adapt or face the consequences of not doing so.
Case study: USA’s Central High Plains:
Professor Robert Aiken a research crop scientist from the K-State Northwest Research-Extension Centre in January of this year outlined the agricultural issues that could surface in the United States if temperatures continue to rise. He focuses on the U.S Central High Plains which run from west-central Texas through west-central Oklahoma, central Kansas, and south-central Nebraska.
He predicts that temperatures will continue to increase in the long-term, caused by increases in CO2 and other greenhouse emissions that continue to build up in the atmosphere. By the middle of the 21st century, temperatures in the Southern Plains will likely be 2.2°C to 3.3°C higher than the 20th century average. This will result in much milder winters with freezing rain instead of snow and hotter summers. Aiken suggests that rainfall predictions are much less certain, but extreme rainfall is expected to continue to become more intense and frequent.
The results of this could be damning for U.S. crop production. Yield potentials would diminish rapidly, triggered by higher night temperatures, which would weaken photo-protection systems in plant life (bio-chemical process that helps organisms cope with molecular damage caused by sunlight) and induce more persistent heat stress.
One positive to increasing temperatures, is that warmer climate could extend the cultivation period for crops. The remarkable tendencies of place life to adapt to extreme climate changes may be the saviour of crop industries in the short term due to the durability of plant metabolic processes. Yet, the positives to extended exposure to sunlight end there as long periods of prolonged heat will likely impair plant productivity.
The fact remains that plant metabolisms are temperature sensitive. Key crops such as winter wheat, rice and maize photosynthesise best at temperatures between 25°C and 30°C. Daily temperatures exceeding this range are likely to slow crop production and damage both the quality and quantity of crop yields.
The consequences according to the report will be sever. Producers will be affected by increases in crop water requirements, the degradation of soil, intensive rainfall events and potential release of large-scale methane emission through thawing permafrost (ground, including rock or soil, at or below the freezing point of water 0°C for two or more years).
Chronic high temperatures will add to the evaporative demand of crop systems. This will lead to a rise in the water requirement for crop growth. Thus, agricultural water-systems will be working at an increased rate, an astounding prospect given the industry today is already the single largest user of freshwater resources, using a global average of 70% of all surface water supplies. These factors will make agriculture in the future progressively more challenging.
A global impact
This research in the US, is equally relevant in the rest of the Western world where rising temperatures will also bring huge agricultural change.
To put this in perspective, 60% of the world’s population rely on wheat, rice and maize for their total calorific intake. This could be hugely damaging given the production distribution of staples like these. For instance, rice production and consumption are highly localised. In a recent study looking at food consumption, Asia alone accounts for 92% of world rice production. In Vietnam, Cambodia and Myanmar, 80% of food consumption derives from rice alone. The same applies to Sub-Saharan Africa and the consumption of Maize, where 90kg to 180kg of the product is consumed per person annually.
"We're most concerned about the sharply reduced yields," said Peter de Menocal, Dean of Science at Columbia University and director of the Center for Climate and Life. "We already have trouble feeding the world and this additional impact on crop yields will impact the world's poorest and amplify the rich/poor divide that already exists."
It is not only staple supply-chains that will be affected, with pressure put on production, iconic exports such as Champagne, Bordeaux wines and Java coffee will be in increasingly short supply. Decreases in crop supply will see surges in demand and prices will rise. The diminishing potential of crop production partnered with an inevitable increase in global population, expected to reach 9.7 billion by 2050 according to the UN/DESA could have disastrous consequences for people around the world.
The UK response
This summer, the United Kingdom is experiencing these symptoms of climate change with an almost unprecedented period of very hot weather. So far, daily temperatures are averaging 20.9C, 0.1C below the hottest summer currently on record (1976). It has also been the driest start to a summer on modern record, with only 47mm of rain having fallen between the 1st June and the 16th July.
Agriculturally, there has been significant disruption. Already farmers are fearing disastrous crop yields due the severe lack of rainfall. Decreased surface water levels have left farms in Derbyshire without water. This does not only offer problems for crop production but also for the well-being of livestock. The significant lack of grass growth in the fields has forced livestock farmers to give winter feedstocks such as hay and silage to animals, or send them for slaughter. It is reported that in some areas, slaughterhouses are struggling to keep with demand as more and more farmers do not have to resources to keep cattle and sheep healthy.
Hot and dry conditions have exposed the UK’s unpreparedness to changes in weather patterns. Derbyshire water supplier Severn Trent have struggled to successfully distribute water tankers to farms, raising concerns around animal welfare.
This has affected the wholesale price of crops. According to the data group Mintec, prices of cauliflowers are up 81%, onions by 55% and carrots by 49% in the four weeks previous to July 18, compared to the same period last year.
Nick Rau, Friends of the Earth farming campaigner, speaking to the Guardian - “Food production is clearly essential, but so are our wildlife-rich rivers. These mustn’t be sucked dry to help prop up unsustainable farming methods. Sustainable farming systems that work with nature are more resilient to extreme weather conditions. Measures such as building up soil carbon will improve soil resilience and help fight climate change.
How does agriculture adapt?
Evidence suggests that the continuance of agricultural processes as they are will see production become increasingly difficult to maintain. Obviously, there is a broader picture within which companies and individuals must turn towards more sustainable practises. But, with our focus on agriculture today, producers must play a significant part in providing a viable alternative to present farming methods.
In the UK, the National Farmers Union (NFU) hosted an agricultural drought summit on 1st August which included representatives from Defra, the Environment Agency (EA), Natural England, the RPA and other farming organisations. The summit aimed to identify both short and medium-term solutions to the challenges currently facing farmers. Subjects tackled included irrigation, water shortage, heat stress on livestock and crop loss. While, agriculture features heavily in the governments Clean Growth Strategyupdated in April 2018.
The Food and Agriculture Organization (FAO) has a clear vision to find a solution to the current climatic conundrum. They feel the solution can be found through the promotion of sustainable practices in various countries. According to the FAO, this would be achievable through the process of agroecology. This entails a series of social and environmental measures that aspire to the creation of a sustainable agricultural system that optimises and stabilises crop yields. Methods would be adaptable, dependent on the demands of a climate. Through this, the supply chain and methods employed could be determined efficiently by policy makers and implemented sustainable by agricultural industries.
By Tom Joslin, Bio-Based World News
Article by: www.biobasedworldnews.com/how-the-global-heatwave-is-harming-agriculture-and-creating-problems-for-the-bio-economy