Climate change crisis: 7.2 billion people could be exposed to losses in food production by 2100 if emissions go unchecked
The recent study follows a UN report, which says that greenhouse gas emissions continue to rise, despite scientific warnings and political commitment, and have increased at a rate of 1.5% per year in the last decade.
The world’s food resources are being exploited at unprecedented rates, and climate change will make things worse, say experts. An estimated 7.2 billion people or 90% of the world’s human population could be exposed to losses of food production in both agriculture and marine fisheries by 2100 if greenhouse gas emissions go unchecked, according to an analysis, which says climate change will impact people’s food loss from both land and sea.
In contrast, fewer than 3% or 0.2 billion people live in regions where increased productivity is predicted for both sectors, under climate change.
“Climate change can alter conditions that sustain food production and availability, with cascading consequences for food security and global economies. Under a “business-as-usual” emission scenario, about 90% of the world’s population -- most of whom live in the most sensitive and least developed countries -- are projected to be exposed to losses of food production in both sectors, while less than 3% would live in regions experiencing simultaneous productivity gains by 2100,” says the study published in Science Advances.
Greenhouse gas levels have reached a record high
The report by multiple institutions -- including National Center for Scientific Research, PSL Université Paris, France; Laboratoire d’Excellence CORAIL, Moorea; and Department of Geography, University of Hawai’i, US -- comes close on the heels of a World Meteorological Organization (WMO) report which says that levels of heat-trapping greenhouse gases in the atmosphere have reached a new record high.
The WMO study shows that globally averaged concentrations of carbon dioxide reached 407.8 parts per million (ppm) in 2018, up from 405.5 parts per million in 2017.
According to WMO experts, what is worse is that there is no sign of a slowdown, let alone a decline, in greenhouse gas concentration in the atmosphere despite all the commitments under the Paris Agreement on Climate Change.
The emissions gap report 2019 by the United Nations (UN) presents a similarly bleak picture. It says that greenhouse gas emissions continue to rise, despite scientific warnings and political commitments. The emissions have increased at a rate of 1.5% per year in the last decade, stabilizing only briefly between 2014 and 2016, and total greenhouse gas emissions, including from land-use change, reached a record high of 55.3 gigatonnes of equivalent carbon dioxide (GtCO2e) in 2018.
The UN experts caution that by 2030, emissions would need to be 25% and 55% lower than in 2018 to put the world on the least-cost pathway to limiting global warming to below 2˚C and 1.5°C, respectively.
Climate change to impact food loss from both land and sea
In the current study, researchers analyzed the vulnerability of societies to the simultaneous impacts of climate change on agriculture and marine fisheries on a global scale. The team used the vulnerability framework developed in the Intergovernmental Panel on Climate Change (IPCC) to predict changes in maize, rice, soy, and wheat agricultural crops in 240 countries, states, or territories, as well as to predict changes in marine fisheries in 194 locations.
The emission scenarios are called Representative Concentration Pathways (RCPs). The researchers looked at two contrasting greenhouse gas emission scenarios: a business-as-usual scenario or RCP8.5, and a strong mitigation scenario or RCP2.6.
The researchers project that under a business-as-usual scenario, where emissions continue to rise, almost the entire world’s human population or 97% will be directly exposed to high levels of change in at least one food production sector by 2100.
“Additionally, 7.2 billion people (about 90% of the world’s future population) would live in countries projected to be exposed to lose-lose conditions, that is, productivity losses in both sectors. These countries generally have high sensitivity and weak adaptive capacity,” say the researchers in their findings.
They say, “Agriculture and marine fisheries are key food production sectors that sustain global food security, human health, economic growth, and employment worldwide, but are substantially and heterogeneously affected by climatic change, with these impacts being projected to accelerate as greenhouse gas emissions rise. Policy decisions on mitigation and adaptation strategies require understanding, anticipating, and synthesizing these climate change impacts.”
The analysis shows that under future climate projections, tropical areas, particularly in Latin America, Central, and Southern Africa, and Southeast Asia, would disproportionately face losses in both agriculture and fisheries. These areas, says the team, are generally highly dependent on agriculture and fisheries for employment, food security, or revenue.
“Conversely, countries situated at high latitudes (for example, Europe and North America) -- where food, jobs, and revenue dependences on domestic agriculture and seafood production are generally lower -- will experience losses of lower magnitude or even gains in some cases (for example, Canada or Russia) under future climate conditions,” says the study.
According to the research team, while the negative consequences of climate change cannot be entirely avoided in some regions of the world, such as Africa, Asia, and Oceania, they have the potential to be drastically lowered if mitigating actions are taken rapidly.
The researchers say that the magnitude of the losses in productivity potential would be considerably lower under RCP2.6 as compared to RCP8.5. This will particularly benefit countries -- set to face losses of food production in both agriculture and marine fisheries -- whose average change in productivity would move from “about −25 to −5% for agriculture and from −60 to −15% for fisheries.”
“Under a strong carbon mitigation scenario (that is, RCP2.6), however, lose-lose situations (in which both agriculture and fisheries are negatively affected) would be reduced by a third, so about 60% of the world’s population,” the experts estimate.
The main improvements, says the analysis, would occur in Africa (all crops and marine fisheries), Asia (mostly marine fisheries and wheat), and South America (primarily wheat and soy), but also in Europe (mostly marine fisheries) and North America (mainly wheat and marine fish).
“Among the 15 countries currently contributing to approximately 80% of the global greenhouse gas production, most would experience net productivity gains (lower losses or losses to gains) in agriculture and fisheries from moving from RCP8.5 to RCP2.6. These include countries with large per capita emissions such as the US, China, and Saudi Arabia,” says the study.