FreeNotes
Chlorofluorocarbons (CFCs) are synthetic chemicals used in refrigeration, air conditioning, aerosol sprays, and foam products. They contribute to ozone depletion because: 1. CFCs are Stable and Reach the Stratosphere: CFCs do not break down in the lower atmosphere and slowly rise to the stratosphere. 2. UV Radiation Breaks Down CFCs: When CFCs reach the stratosphere, … Read more
Global warming is often called the greenhouse effect because it is caused by the trapping of heat in Earth’s atmosphere, similar to how a greenhouse traps heat inside. Explanation of the Greenhouse Effect: 1. The sun’s rays enter the Earth’s atmosphere and warm the surface. 2. The Earth’s surface emits heat in the form of … Read more
Air pollution occurs when harmful substances are released into the atmosphere, affecting human health, wildlife, and the environment. Causes of Air Pollution: Industrial Emissions: Factories and power plants release pollutants such as sulfur dioxide (SO₂), nitrogen oxides (NOₓ), and particulate matter. Vehicle Emissions: Cars, trucks, and motorcycles emit carbon monoxide (CO), hydrocarbons, and nitrogen oxides. … Read more
The greenhouse effect is a natural process where certain gases trap heat from the sun, keeping the Earth warm enough to sustain life. However, human activities have intensified this effect, leading to global warming. Process of the Greenhouse Effect: 1. The sun’s radiation passes through the Earth’s atmosphere. 2. The Earth absorbs some of this … Read more
DIFFERENCE TROPOSPHERE STRATOSPHERE Location The troposphere is the lowest layer of the atmosphere, directly above Earth’s surface. The stratosphere is the second layer above it. Altitude Range The troposphere extends up to 12-18 km above the Earth. The stratosphere extends from about 18 km to 50 km. Temperature Variation In the troposphere, temperature decreases as … Read more
Ozone (O₃) is formed in the stratosphere through a natural process called the ozone-oxygen cycle. Steps of Ozone Formation: 1. UV Radiation Splits Oxygen Molecules: When high-energy ultraviolet (UV-C) radiation from the sun strikes an oxygen molecule (O₂), it splits into two oxygen atoms (O). 2. Oxygen Atoms React with Oxygen Molecules: These free oxygen … Read more
Global warming refers to the long-term rise in Earth’s average temperature due to the excessive accumulation of greenhouse gases (GHGs) such as carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O). These gases trap heat from the sun in the Earth’s atmosphere, preventing it from escaping into space. Causes of Global Warming: Burning Fossil Fuels: … Read more
Ozone depletion refers to the thinning of the ozone layer in the stratosphere due to human-made chemicals, mainly chlorofluorocarbons (CFCs), halons, and other ozone-depleting substances (ODS). These chemicals release chlorine and bromine atoms, which break down ozone molecules. Effects of Ozone Depletion: Increased UV Radiation: More ultraviolet (UV) rays from the sun reach the Earth’s … Read more
Acid rain is precipitation (rain, snow, sleet, or fog) that contains high levels of sulfuric acid (H₂SO₄) and nitric acid (HNO₃). It forms when sulfur dioxide (SO₂) and nitrogen oxides (NOₓ) react with water vapor in the atmosphere. Effects of Acid Rain: Environmental Damage: Acid rain lowers the pH of soil and water bodies, making … Read more
Air pollutants come from both natural and human-made sources. Natural Sources: Volcanic eruptions release sulfur dioxide (SO₂) and particulate matter, which contribute to acid rain and respiratory issues. Forest fires produce carbon monoxide (CO), carbon dioxide (CO₂), and fine particulate matter that cause air pollution. Dust storms, plant pollen, and decaying organic matter also release … Read more