Conversation with Merlin [email protected] · Thu Nov 02 2023

Climate Science: Break down the greenhouse effect – easy on the gas!

The greenhouse effect is a natural phenomenon that plays a crucial role in sustaining life on Earth. Let's break it down in simple terms.

Sunlight, which contains energy, reaches the Earth's surface. Some of this sunlight is reflected back into space, but a significant portion is absorbed by the Earth and its atmosphere. When the Earth absorbs sunlight, it warms up and emits heat in the form of infrared radiation.

Here's where the greenhouse effect comes into play. The Earth's atmosphere contains certain gases called greenhouse gases, such as carbon dioxide (CO2), methane (CH4), and water vapor (H2O). These gases have the ability to trap some of the heat emitted by the Earth, acting like a blanket around our planet.

Just like a greenhouse that traps heat and keeps plants warm, these greenhouse gases trap the heat and prevent it from escaping into space. This process is essential for maintaining a stable temperature on Earth and making it habitable for living organisms.

However, human activities, particularly the burning of fossil fuels like coal, oil, and natural gas, have significantly increased the concentration of greenhouse gases in the atmosphere, especially CO2. This enhanced greenhouse effect has intensified the warming of the Earth's surface, leading to climate change and global warming.

To mitigate the impacts of the greenhouse effect and reduce global warming, it is important to reduce greenhouse gas emissions. This can be achieved by transitioning to renewable energy sources, improving energy efficiency, adopting sustainable agricultural practices, and promoting reforestation.

By understanding and taking action to minimize the greenhouse effect, we can contribute to a healthier and more sustainable planet for future generations.

Greenhouse gases allow sunlight to pass through the atmosphere and heat the planet, but then absorb and redirect some of the longwave radiation (heat) the planet emits. Energy flows down from the sun and up from the Earth and its atmosphere. When greenhouse gases intercept radiation emitted by Earth's surface, they prevent that radiation from escaping into space, causing surface temperatures to rise by about 33C (59F). The greenhouse effect occurs when greenhouse gases in a planet's atmosphere cause some of the heat radiated from the planet's surface to build up at the planet's surface. This process happens because stars emit shortwave radiation that passes through greenhouse gases, but planets emit longwave radiation that is partly absorbed by greenhouse gases. That difference reduces the rate at which a planet can cool off in response to being warmed by its host star. Adding to greenhouse gases further reduces the rate a planet emits radiation to space, raising its average surface temperature. The Earth's average surface temperature would be about 18C (0.4F) without the greenhouse effect,[1][2] compared to Earth's 20th century average of about 14C (57F), or a more recent average of about 15C (59F).[3][4] In addition to naturally present greenhouse gases, burning of fossil fuels has increased amounts of carbon dioxide and methane in the atmosphere.[5][6] As a result, global warming of about 1.2C (2.2F) has occurred since the industrial revolution,[7] with the global average surface temperature increasing at a rate of 0.18C (0.32F) per decade since 1981.[8] The wavelengths of radiation emitted by the Sun and Earth differ because their surface temperatures are different. The Sun has a surface temperature of 5,500C (9,900F), so it emits most of its energy as shortwave radiation in near-infrared and visible wavelengths (as sunlight). In contrast, Earth's surface has a much lower temperature, so it emits longwave radiation at mid- and far-infrared wavelengths (sometimes called thermal radiation or radiated heat).[6] A gas is a greenhouse gas if it absorbs longwave radiation. Earth's atmosphere absorbs only 23% of incoming shortwave radiation, but absorbs 90% of the longwave radiation emitted by the surface,[9] thus accumulating energy and warming the Earth's surface. Terminology The term greenhouse effect comes from an analogy to greenhouses. Both greenhouses and the greenhouse effect work by retaining heat from sunlight, but the way they retain heat differs. Greenhouses retain heat mainly by blocking convection (the movement of air).[10][11] In contrast, the greenhouse effect retains heat by restricting radiative transfer through the air and reducing the rate at which heat escapes to space.[5] Discovery and investigation The existence of the greenhouse effect, while not named as such, was proposed as early as 1824 by Joseph Fourier.[12] The argument and the evidence were further strengthened by Claude Pouillet in 1827 and 1838. In 1856 Eunice Newton Foote demonstrated that the warming effect of the sun is greater for air with water vapour than for dry air, and the effect is even greater with carbon dioxide. She concluded that "An atmosphere of that gas would give to our earth a high temperature..."[13][14] John Tyndall was the first to measure the infrared absorption and emission of various gases and vapors. From 1859 onwards, he showed that the effect was due to a very small proportion of the atmosphere, with the main gases having no effect, and was largely due to water vapor, though small percentages of hydrocarbons and carbon dioxide had a significant effect.[15] The effect was more fully quantified by Svante Arrhenius in 1896, who made the first quantitative prediction of global warming due to a hypothetical doubling of atmospheric carbon dioxide.[16] The term greenhouse was first applied to this phenomenon by Nils Gustaf Ekholm in 1901.[17][18] Eunice Newton Foote recognized carbon dioxide's heat-capturing effect in 1856, a

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The greenhouse effect is a good thing. It warms the planet to temperatures that keep life on earth, well, livable. Without it, the world would be more like Mars: a frozen, uninhabitable place. The problem is, the voracious burning of fossil fuels for energy is artificially amping up the natural greenhouse effect. The result? An increase inglobal warming that is altering the planets climate system. Heres a look at what the greenhouse effect is, what causes it, and how we can temper its contributions to our changing climate. What Is the Greenhouse Effect? What Causes the Greenhouse Effect? What Are Greenhouse Gases? The Consequences of the Greenhouse Effect Solutions for Reducing Greenhouse Gas Emissions What Is the Greenhouse Effect? 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. The process was identified by scientists in the1800s. What Causes the Greenhouse Effect? Sunlight, with the natural greenhouse effect process, makes the earth habitable. Whilearound 30 percent of the solar energythe light and heat from the sunthat reaches our world is reflected back into space, the rest is either absorbed by the atmosphere or the earths surface. This process, which is constantly happening around the globe, warms the planet. This heat is then radiated back up in the form of invisible infrared radiation. While some of this infrared light continues on into space, the vast majority gets absorbed by atmospheric gases, known as greenhouse gases, causing further warming.But higher concentrations of greenhouse gases, and carbon dioxide (CO2) in particular, are causing extra heat to be trapped and average global temperatures to rise. For most of the past 800,000 yearsmuch longer than human civilization has existedthe concentration of CO2 in our atmosphere was roughly between 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. In 2013, driven up largely by the burning of fossil fuels and deforestation, CO2 in the earths atmosphere surpassed 400 parts per milliona concentration not seen on the planet for millions of years. As of 2023, it has reached more than 420 parts per million, which is50 percent higher than preindustrial levels. Credit: Michal Bednarski for NRDC What Are Greenhouse Gases? Earths greenhouse gases trap heat in the atmosphere and warm the planet. The main gases responsible for the greenhouse effect include carbon dioxide,methane, nitrous oxide, and water vapor. In addition to these natural compounds, synthetic fluorinated gases also function as greenhouse gases. Different greenhouse gases have different chemical properties and are removed from the atmosphere, over time, by various processes. Carbon dioxide, for example, is absorbed by carbon sinks such asforests, soil, and the ocean. Fluorinated gases are only destroyed by sunlight in the far upper atmosphere.How much any one greenhouse gas influences global warming depends on three key factors:How much of the gas exists in the atmosphere. Concentrations are measured in parts per million (ppm), parts per billion (ppb), or parts per trillion (ppt). For example, 1 ppm for a given gas means that there is one molecule of that gas in every one million molecules of air.How long the gas remains in the atmosphere, otherwise known as its lifetime.How effective the gas is at trapping heat. This is referred to as its global warming potential (GWP) and is a measure of the total energy that a gas absorbs over a given period of time (usually 100 years) relative to the emissions of 1 ton of carbon dioxide.Radiative forcing (RF) is another way to measure greenhouse gases (and other climate drivers, such as the suns brightness and large volcanic eruptions). Also known as climate forcing, RFindicates the difference between how much of the suns energy gets

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Table of Contents What is the Greenhouse Effect? Greenhouse Gases Causes of Greenhouse Effect Effects of Greenhouse Effect Runaway Greenhouse Effect Greenhouse Effect Definition Greenhouse effect is the process by which radiations from the sun are absorbed by the greenhouse gases and not reflected back into space. This insulates the surface of the earth and prevents it from freezing. What is the Greenhouse Effect? A greenhouse is a house made of glass that can be used to grow plants. The suns radiations warm the plants and the air inside the greenhouse. The heat trapped inside cant escape out and warms the greenhouse which is essential for the growth of the plants. Same is the case in the earths atmosphere. During the day the sun heats up the earths atmosphere. At night, when the earth cools down the heat is radiated back into the atmosphere. During this process, the heat is absorbed by the greenhouse gases in the earths atmosphere. This is what makes the surface of the earth warmer, that makes the survival of living beings on earth possible. However, due to the increased levels of greenhouse gases, the temperature of the earth has increased considerably. This has led to several drastic effects. Let us have a look at the greenhouse gases and understand the causes and consequences of greenhouse effects with the help of a diagram. Also Read:Global Warming Greenhouse Gases Greenhouse gases are the gases that absorb the infrared radiations and create a greenhouse effect. For eg., carbondioxide and chlorofluorocarbons. Greenhouse Effect Diagram The Diagram shows Greenhouse Gases such as carbon dioxide are the primary cause for the Greenhouse Effect The major contributors to the greenhouse gases are factories, automobiles, deforestation, etc. The increased number of factories and automobiles increases the amount of these gases in the atmosphere. The greenhouse gases never let the radiations escape from the earth and increase the surface temperature of the earth. This then leads to global warming. Also Read:Our Environment Causes of Greenhouse Effect The major causes of the greenhouse effect are: Burning of Fossil Fuels Fossil fuels are an important part of our lives. They are widely used in transportation and to produce electricity. Burning of fossil fuels releases carbon dioxide. With the increase in population, the utilization of fossil fuels has increased. This has led to an increase in the release of greenhouse gases in the atmosphere. Deforestation Plants and trees take in carbon dioxide and release oxygen. Due to the cutting of trees, there is a considerable increase in the greenhouse gases which increases the earths temperature. Farming Nitrous oxide used in fertilizers is one of the contributors to the greenhouse effect in the atmosphere. Industrial Waste and Landfills The industries and factories produce harmful gases which are released in the atmosphere. Landfills also release carbon dioxide and methane that adds to the greenhouse gases. Effects of Greenhouse Effect The main effects of increased greenhouse gases are: Global Warming It is the phenomenon of a gradual increase in the average temperature of the Earths atmosphere. The main cause for this environmental issue is the increased volumes of greenhouse gases such as carbon dioxide and methane released by the burning of fossil fuels, emissions from the vehicles, industries and other human activities. Depletion of Ozone Layer Ozone Layerprotects the earth from harmful ultraviolet rays from the sun. It is found in the upper regions of the stratosphere. The depletion of the ozone layer results in the entry of theharmful UV rays to the earths surface that might lead to skin cancer and can also change theclimatedrastically. The major cause of this phenomenon is the accumulation of natural greenhouse gases including chlorofluorocarbons, carbon dioxide, methane, etc. Smog and Air Pollution Smog is formed by the combination of smoke and fog. It can be caused both by natural m

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