Climate change The safe state of food production is dwindling – heat and drought threaten up to a third of cereal production

Humanity agriculture has developed at a time when the climate has been more or less flat. Over the millennia, the regions have found their characteristic grains, such as East Asian rice and Central American corn.

Climate change will upset this balance in this century, says professor of global food and water Matti Kummu From Aalto University.

Heat and drought threaten up to a third of the world’s food production at a time when the world’s population is growing, especially in Africa.

Published last year in the study A group led by Kumpu defined the concept of a safe climate zone.

It refers to an area where currently known varieties and methods are used to grow grain and other food crops or to raise livestock in the current climate.

Provided by 2090, global temperatures will rise by five degrees from pre-industrial times, with 31 per cent of cereal production and 34 per cent of livestock production drifting into a new, threatening situation.

If the rise in temperature remained below two degrees, only eight per cent of cereal production and five per cent of livestock production would drift into climatically foreign waters.

The increase in CO2 emissions would put the greatest strain on food production in India, South-East Asia, Brazil and sub-Saharan Africa.

At worst West Africa’s Benin, Ghana and Guinea-Bissau, South-East Asia’s Cambodia and the small South American countries of Guyana and Suriname would be in trouble. In these, up to 95 percent of food production would fall outside the safe climate zone.

In these countries, society is significantly less able to adapt to change than in rich countries – which are mainly located in the climate-relatively northern regions.

The figures are calculated on the basis of the calories contained in the 27 most important food plants. The area under cultivation would be misleading, as the United States and Europe produce ten times the amount of crops per hectare in some places compared to some fields in sub-Saharan Africa.

Terrestrial the main cereals are rice, wheat, corn and soybeans. According to the modeling of Kumpu and colleagues, climate change treats them unequally.

If the earth were to warm by five degrees, it would threaten two-thirds of current rice production, nearly half of soybean production, but only one-third of wheat and a quarter of corn production.

“Rice is the most climatically demanding, while corn has spread to almost all climatic zones. It withstands heat and drought relatively well, ”says Kummu.

If and when the climate changes in the great plains of eastern China, the population could start replacing rice with corn, for example. Kump and colleagues are conducting a study with the China Agricultural University to try to model such a transition.

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Today, a significant part of the grain goes to feed for farm animals.

To that extent the loss of cereals would not directly cause famine that a significant proportion of cereals today go to feed for farmed animals. People could eat more or just vegetables, so a smaller arable area would suffice.

In particular, most of the soy goes into the mouth of the herd, and the plant protein is converted to animal protein at a rather miserable efficiency.

Soybeans are also grown a lot in the fields cleared in the Amazon rainforest, meaning that giving up meat would stop the Amazon deforestation.

Professor of Molecular and Cell Biology at the University of California Michael Eisen and Emeritus, professor of biochemistry at Stanford University Patrick Brown have recently argued that if humanity gave up all its livestock in a controlled way over the next 15 years, the climate impact of the act would be the same as if annual CO2 emissions were cut by 68%.

Kummu considers that a more vegetarian diet, in addition to reducing food waste, is the key to enabling rich countries to adapt to the threat of climate change to agriculture.

However, he said that would not mean complete veganism.

“Part of meat production is on a sustainable basis because animals eat agricultural by-products such as straw and leaves that are unfit for human consumption. The end-to-end flow of feed could be further enhanced. ”

Meat production can also be partly transformed into “artificial meat” that is produced in the laboratory.

“All kinds of adaptation measures are needed. Reducing both traditional meat production and farmed meat. It is an unsustainable equation that the world’s population would rise to ten billion and everyone would consume the same amount of meat as is consumed in the West today. ”

A large part of the corn crop, in particular, ends up in bioethanol. Admittedly, in the wake of a climate emergency anticipated decades from now, environmental-conscious motoring in the West is likely to be based on an electric motor rather than bioethanol.

Climate global warming is detrimental to crops, mainly through drought and heat.

He recently defended his doctorate from Kumpu’s group Matias Heino found in his dissertationThe corn and wheat are more affected by heat while soy and rice suffer more from drought.

“Rising temperatures increase evaporation and therefore drought. Simultaneous heat and drought are particularly harmful, and they have occurred at the same time in recent decades, especially in wheat growing areas, ”says Heino.

Kummun and a total of 177 countries were included in the Heino Safe Climate Area study.

In 52 of these, food production would remain in a climate-safe area in the future, even if the climate warmed by five degrees from pre-industrial times. Almost all European countries, such as Finland and the Nordic countries, are in a safe climate.

In principle, growth conditions could even be expected to improve in Europe and especially in Finland due to climate change. The growing season lengthens, and an increase in the amount of carbon dioxide accelerates the growth of plants.

When in contact, plants take carbon dioxide from the air and water from the soil at their roots and convert these into glucose and oxygen by the power of sunlight. When there is more carbon dioxide, plants grow faster. That is why carbon dioxide is left in the greenhouses.

“On the other hand, an increase in carbon dioxide may not accelerate growth as desired,” Kummu points out.

A few a year ago in a meta-analysis international research group of the Chinese Academy of Sciences Jinlong Dongin led listed how the increase in carbon dioxide affects vegetables and vegetables.

The increase in carbon dioxide increased the levels of sugar, antioxidants, phenols, flavonoids and vitamin C in vegetables. It reduced the levels of protein, iron, magnesium and zinc.

Nutrition is the protein that is especially important in vegetables if meat intake is to be reduced.

The benefits of a prolonged growing season, on the other hand, are being eroded by the increase in climatic extremes and the spread of pests.

Kummu and Heino estimate that the effects of climate change on the yields of Finnish fields as a whole may be slightly more positive. However, weighing such “everything affects everything” situations is inherently difficult.

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“Genetic modification allows plants to adapt to a changing climate more quickly and specifically.”

In the West According to Kumpu, the alternative would be to move the diet to a more plant-focused diet and reduce food waste. Developing countries, on the other hand, should be able to increase their yields in a sustainable way.

“Most of the food waste in Finland comes from consumers and shops, but not at all at the beginning of the food chain, ie in production and storage,” says Kummu.

“In developing countries, the opposite is true: consumers eat the food they buy carefully, but there is a lot of waste due to inadequate storage.”

Cereals should be developed to better withstand heat and drought. In practice, this means traditional crossing or genetic engineering.

“Genetic modification allows plants to adapt to a changing climate more quickly and specifically. However, there is a risk of possible crosses with natural plants or other varieties. There is not yet enough information on the effects of these junctions. If the seeds are the property of large companies, it will also reduce the power of farmers for their own livelihoods. ”