Before the Industrial Revolution, the greenhouse effect was a natural process in which gases, like carbon dioxide and water vapor, trapped some of the sun's heat within the atmosphere, allowing life to exist on Earth. Human-caused pollution, from factories, fossil fuel combustion and other activities, is contributing to an enhanced greenhouse effect and global warming. (See References 1, p. 2, 3)
Although the atmosphere includes a layer of ozone, ground-level ozone is harmful. Not only does it add to global warming, ground-level ozone is detrimental to human health by causing or worsening respiratory problems. In addition, it negatively impacts ecosystems by damaging vegetation. Each year, ozone causes $500 million worth of reduced crops, according to the U.S. Environmental Protection Agency. Factories involved with industrial processes, like manufacturing metals or chemical solvents, contribute to ground-level ozone production. Power plants, vehicle emissions and burning fossil fuels also produce ozone. Although these processes do not directly release ozone, they produce nitrogen and volatile organic chemicals. When these chemicals combine in the presence of sunlight, they form ozone. (See References 2)
High Global Warming Potential Gases
In an effort to reduce ozone-depleting substances, such as chlorofluorocarbons (CFCs), many industrial facilities are substituting with high global warming potential (GWP) gases. These substitutes are critical to semiconductor, magnesium and aluminum production. In addition, the distribution and transmission of electricity relies on sulfur hexafluoride. GWP gases will likely replace CFCs in fire suppression, refrigeration and other chemical processes. (See References 4) While emissions of these gases are less concentrated than their predecessors, they are potent, synthetic greenhouse gases (see References 6).
Power plants, industrial facilities and vehicles are the main producers of carbon dioxide. In fact, electricity generation releases 41 percent of all carbon dioxide emissions in the U.S., according to the EPA. Petroleum-based transportation is the second-greatest carbon dioxide emitter. Factories, which manufacture metals, chemicals, plastics and minerals, generate carbon dioxide as a byproduct. Commercial buildings and homes also release carbon dioxide. Deforestation contributes to global warming by preventing sequestration, a natural process that involves the absorption of carbon dioxide from the atmosphere into plant foliage. Not only does deforestation decrease the number of trees and plants from sequestering carbon dioxide, cut trees release the gas through decomposition or burning. (See References 3)
As a greenhouse gas, methane is 23 times more potent than carbon dioxide. Although nature releases methane gas on its own, such as from wetlands, wildfires and termite activity, human activities account for an estimated 50 percent of all methane emissions, according to the EPA. Factories, which process natural gas, wastewater or petroleum, contribute to methane gas emissions. In addition, landfills, livestock manure, coal mining and fossil fuel combustion also produce significant quantities of this greenhouse gas. (See References 5)
- U.S. Environmental Protection Agency; Frequently Asked Questions About Global Warming and Climate Change; April 2009
- U.S. Environmental Protection Agency; Ground-Level Ozone; May 2011
- U.S. Environmental Protection Agency; Human-Related Sources and Sinks of Carbon Dioxide; April 2011
- U.S. Environmental Protection Agency; Sources and Emissions: Where Do High GWP Gas Emissions Come From?; June 2010
- U.S. Environmental Protection Agency; Sources and Emissions: Where Does Methane Come From?; April 2011
- U.S. Environmental Protection Agency; Greenhouse Gas Emissions; April 2011
Based in Colorado, Jacqueline Lerche has been writing alternative health, natural science and environment-related articles since 2009. Lerche holds a Bachelor of Science in biology and an Environmental Affairs Certification from Colorado State University.
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