Generated Summary
This document is an overview of greenhouse gases, their sources, and their impact on the atmosphere. It provides information on the main greenhouse gases, including carbon dioxide, methane, nitrous oxide, and fluorinated gases, and their contribution to climate change. The document explains the factors that affect the impact of each gas, such as its concentration, how long it stays in the atmosphere, and how strongly it affects the atmosphere. The information is presented in a concise manner, suitable for providing a basic understanding of the topic. The document refers to data from 2018 and uses the Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990–2018 as its source for emission estimates.
Key Findings & Statistics
- Total Emissions in 2018: 6,677 Million Metric Tons of CO2 equivalent.
- Percentage of Greenhouse Gas Emissions in 2018:
- Carbon Dioxide: 81%
- Methane: 10%
- Nitrous Oxide: 7%
- Fluorinated Gases: 3%
- Carbon Dioxide (CO2): Enters the atmosphere through burning fossil fuels (coal, natural gas, and oil), solid waste, trees and other biological materials, and also as a result of certain chemical reactions.
- Methane (CH4): Is emitted during the production and transport of coal, natural gas, and oil. Methane emissions also result from livestock and other agricultural practices and by the decay of organic waste in municipal solid waste landfills.
- Nitrous Oxide (N2O): Is emitted during agricultural and industrial activities, combustion of fossil fuels and solid waste, as well as during treatment of wastewater.
- Fluorinated Gases: Hydrofluorocarbons, perfluorocarbons, sulfur hexafluoride, and nitrogen trifluoride are synthetic, powerful greenhouse gases that are emitted from a variety of industrial processes.
- Concentration of Greenhouse Gases: Measured in parts per million, parts per billion, and even parts per trillion.
- One part per million: Equivalent to one drop of water diluted into about 13 gallons of liquid.
- Gases with a higher GWP absorb more energy, per pound, than gases with a lower GWP, and thus contribute more to warming Earth.
Other Important Findings
- Greenhouse gases trap heat in the atmosphere.
- The effect of each gas on climate change depends on its concentration, how long it stays in the atmosphere, and its impact.
- Each gas can remain in the atmosphere for different amounts of time, ranging from a few years to thousands of years.
- All of these gases remain in the atmosphere long enough to become well mixed, meaning that the amount that is measured in the atmosphere is roughly the same all over the world, regardless of the source of the emissions.
- A Global Warming Potential (GWP) has been calculated to reflect how long it remains in the atmosphere, on average, and how strongly it absorbs energy.
Limitations Noted in the Document
- The percentages of emissions may not add up to 100% due to independent rounding.
- The document provides a general overview and does not go into detailed scientific analysis.
- The document relies on data from a specific year (2018) and may not reflect current emission trends accurately.
- The document does not discuss the specific methodologies used to collect or calculate the emission data.
- The overview lacks a detailed discussion of the sources of all greenhouse gasses.
Conclusion
The document provides a brief overview of greenhouse gases, their sources, and their impacts on climate change, with statistics from 2018. The key takeaways are that greenhouse gases trap heat, and their impact depends on their concentration, lifespan, and ability to absorb energy. While the document offers a foundational understanding, it is limited in scope. The information highlights the complexity of climate change, where multiple factors contribute to the warming of the planet. The document emphasizes the importance of understanding the sources and impacts of greenhouse gases to address climate change effectively. The provided information underscores the need for more comprehensive studies and updated data to gain a complete picture of greenhouse gas emissions and their effects. The use of GWP as a metric is important as it allows for a better comparison of the warming impact of each greenhouse gas. The document serves as a basic introduction to the complex issue of greenhouse gases. It calls to action to address the issue.