Basically, the greenhouse effect is the phenomenon in which the amount of heat radiated by the earth is disproportionate to the heat received by the atmosphere. This is done by a process called “positive feedback”. This means that if the earth’s temperature rises, the amount of heat received will rise, and the same is true if the earth’s temperature drops. It is also important to understand that while this is a natural phenomenon, it is human activity that has contributed to the increase in the rate of global warming.
Common misconceptions
Various researchers have delved into the complexities of the greenhouse effect. While there is debate about whether or not humans are responsible for the change, there is agreement that there is an increase in greenhouse gases. These gases are released by human activities
In the past hundred years, the concentration of carbon dioxide has increased by nearly 400 parts per million. This is the first time the levels of the gas have risen that much.
Among the major greenhouse gases, methane (CH4) is the second-largest contributor to global warming. In addition to its direct impact on the Earth’s climate, methane can also be a significant contributor to ground-level ozone, a toxic air pollutant. Approximately 1 million people die each year from exposure to ground-level ozone.
Methane is a colorless, odorless, and relatively short-lived gas that is found naturally in the atmosphere. It is produced in several different ways, including from the decomposition of organic matter in wetlands, and the digestion of animal waste. It is also generated through the use of fossil fuels.
Carbon dioxide
Among the gases in the Earth’s atmosphere, carbon dioxide plays a very important role in climate change. Carbon dioxide is a molecule composed of one carbon atom and two oxygen atoms. It is made up of less than a one-thousandth of a percent of the earth’s air, yet it has a profound impact on our climate.
Carbon dioxide and other greenhouse gases in the atmosphere absorb solar heat and radiate it back in all directions. This heat is trapped by the molecules and is the cause of global warming.
Agricultural soil management produces the largest proportion of human-induced N2O emissions in the United States. Nitrous oxide is an important greenhouse gas and also an ozone depleting chemical. It is produced during combustion of fossil fuels, land use activities, and chemical production. It is also emitted by wastewater applications.
The main human-induced source of surface ozone is photochemical reactions with atmospheric pollutant carbon monoxide. Natural sources include subsidence of stratospheric ozone and air pollution.
The concentration of greenhouse gases in the atmosphere has been particularly high during warm periods. The concentration of carbon dioxide (CO2) in the atmosphere has increased by about 149% in the last century. However, concentrations have been much lower during cold periods.
Water vapor is a positive feedback mechanism
Despite the name, water vapor feedback is not the only feedback mechanism for the greenhouse effect. Clouds are a major positive feedback, but the extent and magnitude of this feedback is uncertain. Similarly, aerosols play a role in climate change, but the exact magnitude of their contribution is not known. Nevertheless, the presence of water vapor feedback in the atmosphere is important to the climate system.
This feedback is a positive one, because increased atmospheric water vapor reduces the longwave radiative damping of temperature anomalies. This means that warmer surface-troposphere temperature anomalies will lead to increased water vapor in the air, which will further enhance the greenhouse effect. Depending on the scale of the anomaly, this feedback will have a larger or smaller impact.
First detection in 1824
Whether you agree or disagree with the attribution of credit to Jean Baptiste Joseph Fourier, you cannot deny that he made a good attempt at measuring and comparing the properties of various gases. In a nutshell, the spectral heat absorptive ability of the most important greenhouse gas is measured to a degree of precision. This is not only a very useful metric for climate science, but is also an invaluable benchmark for those trying to improve our planetary health.
Fourier was not alone in attempting the impossible feat. The aforementioned ice cores likewise provide an insight into the genesis of the aforementioned miracle gas.
Human involvement in climate change
Despite the controversy, the majority of climate scientists agree that Earth is warming. They also recognize that human activity is primarily responsible for this warming.
The greenhouse effect, which is essential for life on Earth, is the result of greenhouse gases trapping heat from the planet before it escapes into space. Since humans have increased the abundance of these heat-trapping gases, the temperature of the planet is rising.
The warming is mainly caused by the burning of fossil fuels. During the Industrial Revolution, the amount of carbon dioxide in the atmosphere has increased by about 50%. Today, the atmospheric concentration of CO2 is more than 400 parts per million.
