The greenhouse effect is the process that occurs when energy from a planet’s host star passes through the planet’s atmosphere and heats up its surface. This energy is then trapped in the atmosphere by a layer of greenhouse gases, which prevent the heat from returning to space. As a result, a planet’s surface becomes warmer and more habitable.
Methane
The Global Monitoring Laboratory at the National Oceanic and Atmospheric Administration receives air samples from monitoring stations around the world. These samples could help scientists answer the question of why there’s so much methane in the atmosphere. Since the industrial revolution, methane emissions have more than doubled – from seventy-two parts per billion in 1750 to eighty-four parts per billion in 2015. In recent years, however, methane emissions have slowed down in many developed countries.
Methane is a natural greenhouse gas produced by plants, fungi, algae, and bacteria. In the presence of oxygen, it can cause the Earth’s temperature to increase. The release of methane is a significant contributor to the greenhouse effect and is estimated to account for 10 to 30 percent of global emissions each year. The largest emissions come from hot, tropical regions.
The sources of methane are diverse, which makes identifying solutions difficult. Despite this, many studies have focused on the role of diet in reducing emissions. Eating less processed foods, such as starch-based foods, can reduce methane by as much as thirty percent. Furthermore, eliminating these food sources may improve the nutritional value of milk. Increasing algae-rich diets and species-selection in farming can also reduce methane emissions.
While methane is not the main contributor of global warming, it is the second-most common greenhouse gas. It absorbs more heat than carbon dioxide and plays a more important role in the warming of the planet. In fact, it has been estimated that methane is responsible for one-fifth of global warming.
Carbon dioxide
Human activities have greatly increased the levels of greenhouse gases in the atmosphere. Today, CO2 concentrations are many times higher than they were during the pre-industrial era. Until recently, the natural background level of carbon dioxide in the atmosphere fluctuated at a slow rate. But today, the rate of growth has tripled over the past half century.
Before the 1970s, greenhouse-emissions research hardly interacted with other subjects. However, during that time, it became a major focus of research in a number of overlapping fields. By that time, scientists had determined that more than half of the human effect on climate change was due to CO2 emissions, mainly from burning fossil fuels and cement-making industries. The rest came from the release of other gases, atmospheric pollution, and changes in land use.
The amount of carbon dioxide society pumps into the atmosphere is staggering. In the last century, humanity dumped two hundred and twenty billion tons of carbon dioxide into the air and added an additional 110 billion tons through land-use changes and deforestation. Currently, the atmosphere weighs five quadrillion tons, and carbon dioxide is a tiny fraction of that. Despite its small size, carbon dioxide is growing every year. In fact, the International Energy Agency has predicted that CO2 emissions will reach forty billion tons by 2030.
The greenhouse effect is caused by carbon dioxide, which absorbs infrared radiation. Its effect is dependent on its chemical makeup and its relative concentration in the atmosphere. Some greenhouse gases are better than others at absorbing infrared radiation, while others are worse. Scientists have long suspected that the increase in CO2 concentration has been contributing to global warming.
Chlorofluorocarbons
Halocarbons are powerful greenhouse gases and stay in the atmosphere for decades. They warm the Earth many times faster than CO2, the most abundant greenhouse gas in the atmosphere. However, human activity still emits more CO2 than halocarbons. Therefore, these gases have largely been replaced by other, lower-potential greenhouse gases.
There is some controversy surrounding CFCs and their impact on climate change, but they are not a major cause of global warming. The chemical compounds are only a problem when they leak from their source, which could be a refrigeration or air conditioning unit in a building or car. The good news is that halocarbons can be recovered and used in different parts of the climate system.
The use of CFCs and other halogen-source gases has also been linked to the destruction of the ozone layer. The removal of the ozone layer by humans has resulted in increased risks of skin cancer and climate change. The use of halocarbons, which are known as ozone-depleting gases, has caused the hole in the ozone layer to grow. This can damage crops, and increase the risk of skin cancer.
Chlorofluorocarbons have caused stratospheric ozone layer depletion. As a result, they are now banned in many areas. The depletion of the ozone layer threatens the biodiversity of the planet. The excessive radiation hitting the Earth’s surface will destroy plant life, destroy agricultural productivity, and increase the risk of skin cancer.
Sulfur hexafluoride
As the nation works to address the issue of long-term climate change, researchers are focusing on sulfur hexafluoride, a greenhouse gas that is more than 22 times more potent than carbon dioxide. It is also a persistent chemical, remaining in the atmosphere for thousands of years. In fact, one pound of sulfur hexafluoride has the same impact as more than a million pounds of coal. The study is a critical step in assessing the effect of the gas on the environment.
Despite the fact that SF6 is the world’s most potent greenhouse gas, it is still widely used in the electrical industry. It is used in switchgear and is a vital component of the power grid. The chemical is colorless and nonflammable, making it a great insulator for high-voltage electrical installations.
Sulfur hexafluorides are non-polar and colorless. Their chemical properties are also inert, meaning that they are readily condensed into liquid state. However, they do not react with lithium or molten sodium below their boiling points.
Sulfur hexafluorides are not naturally occurring substances. However, they can be produced by humans. Historically, they have been used in the production of chemical weapons, such as disulfur decafluoride. These compounds have high global warming potential, and are also a health risk to workers.
Nitrogen trifluoride
Nitrogen trifluoride is a powerful greenhouse gas that is produced in industrial quantities. However, it is not regulated by the Kyoto Protocol and its emission rates are not known. Scientists are now recommending that nitrogen trifluoride be added to the list of greenhouse gases and regulated under the Kyoto Protocol. Its use in electronics, such as thin-film solar panels, liquid crystal displays, and microcircuits, makes it an important greenhouse gas.
Currently, it is not recognized as a major industrial gas under the Kyoto Protocol and was not even listed by the United Nations’ Intergovernmental Panel on Climate Change in 1995. In contrast, new research has shown that the amount of NF3 is about four times greater than previously thought. In fact, the amount of nitrogen trifluoride has been growing by eleven percent each year since 2006.
Nitrogen trifluoride (NF3) has a long life cycle and is capable of trapping a significant amount of heat. While its use is predominantly in Northern Hemisphere countries, it is still a significant contributor to greenhouse gas emissions. Its presence in the atmosphere is equivalent to about 16 percent of the total greenhouse gas emissions.
According to the United Nations Framework Convention on Climate Change, NF3 is one of the five most prominent new greenhouse gases. Hence, it is likely to be included in the next phase of global warming regulation. Its inclusion in the next phase of global warming regulation indicates the complexity of the problem.
Water vapor
One of the major causes of Earth’s warming is water vapor. This gas is emitted by human beings, particularly from agriculture. The greenhouse warming potential of water vapor is about one thousand times less than carbon dioxide. Yet it is the largest contributor to anthropogenic water vapor emissions.
Water vapor cycles rapidly through the atmosphere. It evaporates from the oceans and other locations, and increases with the temperature. Water vapor also absorbs heat from Earth, which makes the atmosphere warmer. Scientists believe this process creates a positive feedback loop, amplifying the effect of warming.
Water vapor is responsible for about 60% of the Earth’s greenhouse effect. It is an effective greenhouse gas, but it does not cause warming on its own. The amount of water vapor that is in the atmosphere is directly proportional to the temperature, and the warmer the air, the more water vapor it can hold. In recent years, the amount of water vapor in the atmosphere has increased by 0.41 kilograms per square meter every ten years.
The total water vapor content of the oceans has increased by 0.41 kg/sq meter every decade since 1988. This increase is largely due to increased atmospheric ozone. This oxidation of methane releases the water vapor.
