Is agriculture the leading cause of global warming?
The Problem A new report released by the United Nations Intergovernmental Panel on Climate Change, which examines how land use changes have contributed to the warming of Earth’s atmosphere, has concluded that agriculture and forestry have contributed nearly a quarter of global greenhouse gas emissions.
What percentage of global carbon emissions come from agriculture?
They do also provide a separate estimate which includes non-food products; this estimates that agricultural products as a whole contributes 33% to global emissions.
What are the top 3 sources of greenhouse gases?
In the United States, most of the emissions of human-caused (anthropogenic) greenhouse gases (GHG) come primarily from burning fossil fuels—coal, natural gas, and petroleum—for energy use.
What are the top 3 sources of greenhouse gas emissions?
Most of the world’s greenhouse gas emissions come from a relatively small number of countries. China, the United States, and the nations that make up the European Union are the three largest emitters on an absolute basis. Per capita greenhouse gas emissions are highest in the United States and Russia.
Other indirect impacts from changed conditions
It is difficult to project the impact of climate change on utilization (protecting food against spoilage, being healthy enough to absorb nutrients, etc.) and on volatility of food prices. Most models projecting the future do indicate that prices will become more volatile. In 2019 the IPCC stated that millions already suffer from food insecurity due to climate change. As of 2019, an estimated 831 million people are undernourished. Climate change impacts depend strongly on p…
Direct impacts from changing weather patterns
As the temperature and weather patterns change, areas suitable for farming will alter. The current prediction is for temperature increase and precipitation decrease for major arid and semi-arid regions (Middle East, Africa, Australia, Southwest United States, and Southern Europe). In addition, crop yields in tropical regions will be negatively affected by the projected moderate increase in temperature (1-2 °C) expected to occur during the first half of the century. During the second hal…
Direct impacts from increased atmospheric CO2 levels
Elevated atmospheric carbon dioxide affects plants in a variety of ways. Elevated CO2 increases crop yields and growth through an increase in photosynthetic rate, and it also decreases water loss as a result of stomatal closing.
Changes in atmospheric carbon dioxide may reduce the nutritional quality of some crops, with for instance wheat having less protein and less of some minerals. Food crops could see a reductio…
Climate driven changes in pests, plant diseases and weeds (indirect impacts)
Global aggregate estimates for crop yields
Impacts on forests and forestry
The IPCC Sixth Assessment Report in 2022 found that: “In the past years, tree mortality continued to increase in many parts of the world. Large pulses of tree mortality were consistently linked to warmer and drier than average conditions for forests throughout the temperate and boreal biomes. Long-term monitoring of tropical forests indicates that climate change as begun to increase tree mortality and alter regeneration. Climate related dieback has also been observed du…
Adaptation in agriculture is often not policy driven, but farmers make their own decisions in response to the situation they face. Changes in management practices might be the most important adaptation option.Changes in locations of agriculture and international trade in food commodities might also contribute to adaptation efforts.
Agricultural innovation is essential to addressing the potential issues of climate change. This in…
Agriculture is the growing of plants (crops) and animals (livestock) for food and other purposes. In 2007, lands used for crop growing and animal grazing took up 40–50% of Earth’s land surface, a 10% increase since 1961. Agriculture contributes to global climate change by releasing carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), the t…
Historical Background and Scientific Foundations
For most of the human race’s existence, it did not practice agriculture. For many hundreds of thousands of years, humans and their near-human ancestors practiced various forms of hunting and gathering, finding edible plants and animals in the environment rather than raising them. The first known tools, made about 2.5 million years ago, were food processors, chipped stones devis…
Impacts and Issues
- Is Meat the Number One Cause of Global Warming?
In 2007, vegan and animal-rights organizations ran ads in the U.S. media stating that emissions from meat-raising contribute more to global warmingthan cars do. For example, an ad by the group People for the Ethical Treatment of Animals (PETA) read: “Too Chicken to Go Vegetarian? …
- Mitigation of Agricultural Emissions
Altered agricultural practices can reduce agriculture’s contribution to global warming. More efficient delivery of nitrogen to crops would reduce N2O emissions and other ecological harms; livestock management for more efficient digestion of feeds would save money and reduce CH4…
Primary Source Connection
Methane (CH4) and nitrous oxide (N2O) are major greenhouse gases. Agriculture is a common, and often overlooked, contributor of methane and nitrous oxide. Both methane and nitrous oxide are produced naturally by livestock and soil management. Some human-controlled agricultural management techniques, however, increase methane and nitrous oxide production. This article …
Parry, M. L., et al, eds. Climate Change 2007: Impacts, Adaptation and Vulnerability: Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. New York: Cambridge UniversityPress, 2007.
Asner, Gregory P. “Grazing Systems, Ecosystem Responses, and Global Change.” Annual Review of Environment and Resources29 (2004): 261–299. Deutsch, Claudia H. “Trying to Connect the Dinner Plate to Climate Change.” The New York Times(August 29, 2007). Izaurralde, R. César, et …