Gases that trap heat in the atmosphere are called greenhouse gases. Identified by scientists as far back as 1896, the greenhouse effect is the natural warming of the earth that results when gases in the atmosphere trap heat from the sun that would otherwise escape into space.
To quote directly from the NRDC, “Sunlight makes the earth habitable. While 30 percent of the solar energy that reaches our world is reflected back to space, approximately 70 percent passes through the atmosphere to the earth’s surface, where it is absorbed by the land, oceans, and atmosphere, and heats the planet. This heat is then radiated back up in the form of invisible infrared light. While some of this infrared light continues on into space, the vast majority—indeed, some 90 percent—gets absorbed by atmospheric gases, known as greenhouse gases, and redirected back toward the earth, causing further warming.
For most of the past 800,000 years—much longer than human civilization has existed—the concentration of greenhouse gases in our atmosphere was between about 200 and 280 parts per million. (In other words, there were 200 to 280 molecules of the gases per million molecules of air.) But in the past century, that concentration has jumped to more than 400 parts per million, driven up by human activities such as burning fossil fuels and deforestation.” Because many of the major greenhouse gases stay in the atmosphere for tens to hundreds of years after being released, their warming effects on the climate persist over a long time and can therefore affect both present and future generations.They are the most significant driver of observed climate change since the mid-20thcentury.
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 (e.g., manufacture of cement). Carbon dioxide is removed from the atmosphere (or “sequestered”) when it is absorbed by plants as part of the biological carbon cycle.
It’s easy to forget carbon dioxide isn’t the only greenhouse gas in town. But a spate of developments in the Spring of 2021 has reigniting the dialogue about the importance of addressing super pollutants — substances including methane (which is emitted during the production and transport of coal, natural gas, and oil as well as resulting from livestock , other agricultural practices, land use & decay of organic waste in municipal landfills); nitrous oxide (emitted during agricultural, land use, industrial activities, combustion of fossil fuels and solid waste, as well as during treatment of wastewater), and fluorinated gases such as hydrofluorocarbons , perfluorocarbons, sulfur hexafluride, and nitrogen trifluoride (synthetic, powerful greenhouse gases that are emitted from a variety of industrial processes).
Larger emissions of greenhouse gases lead to higher concentrations in the atmosphere. The EPA has an effective page illustrating how atmospheric concentrations of greenhouse gases have accelerated over time.
Each of these gases can remain in the atmosphere for different amounts of time, ranging from a few years to thousands of years. They all remain 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.
Some gases are more effective than others at making the planet warmer and “thickening the Earth’s blanket.” The EPA has that covered as well.
While super-polluting greenhouse gas emissions don’t last in the atmosphere as long as CO2 (living decades rather than centuries), they do plenty of damage while they’re hanging around, accelerating the pace of global warming. Conversely, if we act to address them, they offer an important path for starting to bring down temperatures quickly in the short term — while we get our act together to work on longer-term climate solutions.
For the past four years, U.S. action around most super pollutants (with the exception of nitrogen oxide) has come from states and cities, with the cooperation of some industry associations. That’s changing under the Biden administration.
- In late April, a bipartisan vote in the U.S. Senate reinstatedan Obama-era regulation that requires oil and gas companies to monitor and repair methane leaks along pipelines, at storage facilities and in extraction operations (one of more than 100 environmental rules slashed by former President Trump).
- The Department of Energy (DoE) in April committed $35 million into climate tech specifically focused on the methane mess, which it estimates contributes about 10 % of annual GHG emissions. The funding is focused on solutions for dealing with the exhaust from natural gas engines; rethinking the practice of flaring; and handling coal mine ventilation.
- The U.S. Environmental Protection Agency also announcedit is moving forward to phase down HFCs, mainly used for refrigerators and air conditioners. This measure, according to the EPA and the legislators supporting this action, would help to avoid 0.5 degrees of warming by 2100. The rule falls under the American Innovation and Manufacturing Act, a piece of bipartisan legislation adopted in late 2020 that provides “regulatory certainty” for decreasing the production and import of HFCs into the U.S. by 85 percent over the next 15 years.
The need to deal with methane, linked closely with natural gas production, is urgent. A United Nations study issued in May, 2021 suggested that focusing on methane reductions from fossil fuels activities, landfills and agricultural production could help avoid almost 0.3 degrees Celsius of warming by the early 2040s. JPMorgan Chase even referenced methane leaks and monitoring in its proclamation last week about how it will scrutinize its financing related to carbon-intensive industries like the oil and gas sector.
What climate-tech superheroes hope to play a role in combating these super-pollutant villains? Look to our NEW TECHNOLOGIES page.
Some of these investments will no doubt be controversial with climate activists, who are likely to argue (legitimately) that they perpetuate natural gas extraction processes. There is no doubt, however, that regulating methane gas is critical for advancing President Joe Biden’s goal to slash U.S. emissions in half from 2005 levels over the next decade and achieve a net-zero economy by 2050.