Intergovernmental Panel on Climate Change (IPCC) vice-chairs Thelma Krug of Brazil and Ko Barrett of the US attend the opening meeting of the 50th session of the United Nations body for assessing the science related to climate change, on August 2 in Geneva.FABRICE COFFRINI/AFP/Getty Images
Without a drastic overhaul of agricultural practices and the way we eat, extreme weather events, water scarcity and soil erosion driven by climate change will threaten the stability of the global food supply.
The warning comes from a report from the United Nations’ Intergovernmental Panel on Climate Change (IPCC) released Thursday. It outlines how rising temperatures have already affected our food system – from changing precipitation patterns to coastal degradation to tropical crop yield decline – and how those threats are likely to escalate in the absence of urgent action.
The report makes clear that food production itself is a major part of the problem. Together with deforestation (which most commonly means converting forest to agriculture land), agriculture contributes 44 per cent of methane emissions and 23 per cent of all human-caused greenhouse gas emissions. Factoring in other activities along the food supply chain, such as fertilizer production, food processing and transportation, that figure increases to between 21 per cent and 37 per cent of greenhouse gas emissions.
“If we want to address global climate change, we need to involve the land sector, because it is both part of the problem and part of the solution,” said Werner Kurz, one of the report’s lead authors and a senior research scientist with Natural Resources Canada. “The choices we make about how we eat and feed humanity also influence future greenhouse gas emissions.”
Without intervention, emissions from agriculture are poised to further increase, according to the report, driven by “population and income growth and changes in consumption patterns." The world’s population is expected to increase to 9.7 billion by 2050 from 7.7 billion.
“Climate change has already affected food security due to warming, changing precipitation patterns and greater frequency of some extreme events," the report says. “The stability of food supply is projected to decrease as the magnitude and frequency of extreme weather events that disrupt food chains increase."
According to the report, current levels of global warming are associated with “moderate" risk of effects including dryland water scarcity, wildfire damage and permafrost degradation. With a 1.5-degree C increase, the risk changes to “high.” At around two degrees of global warming, the risk from permafrost degradation and food supply instabilities are projected at "very high.”
The report was co-authored by dozens of scientists from around the world, and the IPPC formally accepted the findings in Geneva this week. The IPCC is a UN body tasked with assessing science related to climate change.
The authors recommend a wide variety of responses. They outline a number of options of improving livestock management, the use of higher-quality feed and improved manure management.
Reducing food waste is another recommendation – currently, between 25 per cent and one-third of the food produced globally is wasted, contributing up to 10 per cent of greenhouse gas emissions.
potential impact of agriculture
on food security
A report from the United Nations’ Intergovernmental Panel on Climate Change warns of the impacts of agriculture on climate change – and the effect growing greenhouse gas emissions might have on
future food security.
change in temperature relative
to 1850-1900
In degrees Celsius
Change in surface air temp. over land
Change in global mean surface temp.
(land-ocean)
2.0˚
1.5
1.0
0.5
0.0
-0.5
1880
1920
1960
2000
1850
1900
1940
1980
2018
change in ghg emissions
In gigatonnes of CO2 equivalent/year
Nitrus oxide from agriculture
Methane from agriculture
Net CO2 emissions from FOLU*
4
3
2
1
0
1961
1980
2000
2016
*From land use activities
risks to humans and ecosystems
because of climate change
According to the report, a 2°C increase in temperatures would increase the risks of effects like dryland water scarcity and and food supply instability from “moderate” to “very high.”
Chart key: level of impact/risk
Impacts
Risks
1
2
3
4
Undectable: Impact/risks are undetectable
1
Moderate: Impacts/risks are detectable
and attributable to climate change
with at least medium confidence
2
High: Significant and widespread
impacts/risks
3
Very high: Very high probability of severe impacts/risks and presence of significant reversibility/persistence of climate-related hazards, combined with limited ability to adapt
4
Global mean surface temperature (GMST)
change relative to levels in preindustrial time,
in degrees Celsius
0.0
1.0
3.0
4.0
5.0˚
2.0
Dryland water
scarcity
2006-2015
Soil
erosion
Vegetation
loss
Wildfire
damage
Permafrost
degradation
Tropical crop
yield declline
Food supply
instability
john sopinski/the globe and mail, source:
united nations’ intergovernmental panel on
climate change
potential impact of agriculture
on food security
A report from the United Nations’ Intergovernmental Panel on Climate Change warns of the impacts of agriculture on climate change – and the effect growing greenhouse gas emissions might have on
future food security.
change in temperature relative to 1850-1900
In degrees Celsius
Change in surface air temp. over land
Change in global mean surface temp. (land-ocean)
2.0˚
1.5
1.0
0.5
0.0
-0.5
1880
1920
1960
2000
1850
1900
1940
1980
2018
change in ghg emissions
In gigatonnes of CO2 equivalent/year
Nitrus oxide from agriculture
Methane from agriculture
Net CO2 emissions from FOLU*
4
3
2
EMBARGOED
1
0
1961
1980
2000
2016
*From land use activities
risks to humans and ecosystems
because of climate change
According to the report, a 2°C increase in temperatures would increase the risks of effects like dryland water scarcity and and food supply instability from “moderate” to “very high.”
Chart key: level of impact/risk
Impacts
Risks
1
2
3
4
Undectable: Impact/risks are undetectable
1
Moderate: Impacts/risks are detectable and
attributable to climate change with at least
medium confidence
2
High: Significant and widespread impacts/risks
3
Very high: Very high probability of severe impacts/risks and presence of significant reversibility/persistence of climate-related hazards, combined with limited ability to adapt
4
Global mean surface temperature (GMST) change relative
to levels in preindustrial time, in degrees Celsius
0.0
1.0
3.0
4.0
5.0˚
2.0
Dryland water
scarcity
2006-2015
Soil
erosion
Vegetation
loss
Wildfire
damage
Permafrost
degradation
Tropical crop
yield declline
Food supply
instability
john sopinski/the globe and mail, source:
united nations’ intergovernmental panel on
climate change
potential impact of agriculture on food security
A report from the United Nations’ Intergovernmental Panel on Climate Change warns of the impacts of agriculture on climate change – and the effect growing greenhouse gas emissions might have on
future food security.
change in temperature relative to 1850-1900
In degrees Celsius
Change in surface air temp. over land
Change in global mean surface temp. (land-ocean)
2.0˚
1.5
1.0
0.5
0.0
-0.5
1850
1880
1900
1920
1940
1960
1980
2000
2018
change in ghg emissions
In gigatonnes of CO2 equivalent/year
Nitrus oxide from agriculture
Methane from agriculture
Net CO2 emissions from FOLU*
4
3
2
1
0
1961
1980
2000
2016
*From land use activities
risks to humans and ecosystems because of climate change
According to the report, a 2°C increase in temperatures would increase the risks of effects like dryland water scarcity and and food supply instability from “moderate” to “very high.”
Chart key: level of impact/risk
Very high: Very high probability of severe impacts/risks and presence of
significant reversibility/persistence of climate-related hazards, combined
with limited ability to adapt
High: Significant and widespread impacts/risks
Risks
Moderate: Impacts/risks are detectable and attributable to climate change
with at least medium confidence
Impacts
Undectable: Impact/risks are undetectable
Global mean surface temperature (GMST) change relative to levels in preindustrial time,
in degrees Celsius
5.0˚
4.0
3.0
2.0
1.0
2006-2015
0.0
Dryland water
scarcity
Soil
erosion
Vegetation
loss
Wildfire
damage
Permafrost
degradation
Tropical crop
yield declline
Food supply
instability
john sopinski/the globe and mail, source: united nations’
intergovernmental panel on climate change
The authors also recommend “diversification” of the food system – including encouraging diets based heavily on plants and grains. “Grain and plant-based diets require much less land to produce then, say, a high-meat, protein-based diet,” said Mr. Kurz.
The report highlights the major contradictions in our global food system. Since 1961, the availability of food has increased (the supply of meat per capita, for example, has more than doubled). Yet at the same time, some 821 million people around the world are undernourished.
“The scientific breakthroughs that were so successful in boosting yields in the 20th century to fight global hunger are now threatening our food system,” said a statement from David Festa, a senior vice-president for the Environmental Defense Fund. He called for farmers and ranchers to improve fertilizer efficiency, monitor their water use and adopt practices to store more carbon in the soil.
“We urgently need technological and policy innovations to help more farmers and ranchers break through entrenched cultural, economic and political barriers and adopt these practices."
The effects of climate change are expected to reach all corners of the globe, according to the report. In Asia and Africa, desertification is expected to hit populations the hardest. Wildfires are expected to increase across North America, South America, the Mediterranean, southern Africa and Central Asia. And tropical and subtropical areas are most vulnerable to crop yield decline.
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Ann Hui