atmospheric-chemistry and maintaining our atmosphere

chemistry about atmospheric chemistry

1. Atmospheric Chemistry

2. Composition and Structure of the atmosphere

3. Composition and Structure of the atmosphere The word atmosphere comes from the Latin word atmosphaera , which contains the Greek roots " atmós " meaning vapor or steam, " sphaîra " meaning globe or planetary sphere Atmosphere is a layer of gas and suspended solids extending from the Earth’s surface up many thousands of miles becoming increasingly thinner with distance but always held by the Earth’s gravitational pull What is Atmosphere?

4. What is Atmospheric Chemistry? This is the study of the chemical processes that occur in the atmosphere.it includes the underlying chemistry that governs air pollution and global change from gases and particles emitted into the atmosphere. Composition of the Atmosphere Earth's atmosphere is composed of about 78% nitrogen , 21% oxygen, and one percent other gases. These gases are found in atmospheric layers ( troposphere, stratosphere, mesosphere, thermosphere, and exosphere ). Earth’s atmosphere composition The Earth’s atmosphere is made up of many different gases. At the lower levels, nitrogen and oxygen are the most abundant gases. One of the most important things to remember about Earth’s atmosphere is that it is dynamic, meaning what we see today may not be the same as what we see years from now.

5. From largest to smallest, Earth’s atmosphere composition contains nitrogen, oxygen, argon, CO2, and trace gases. Because water vapor is highly variable geographically, it’s excluded from this total.  Nitrogen (78.1%) - Nitrogen is incredibly stable and requires a lot of energy to change forms.  Oxygen (20.9%) - Oxygen is essential to human life as our lungs respire oxygen and uses it in metabolism. Argon(0.93%) - Argon makes up 0.93% of the Earth's atmosphere and is the third most abundant atmospheric gas. Carbon Dioxide (0.04%) - Carbon is the most important element for building molecules essential for living things. Trace Gases - They are called trace gases because they exist in small amounts. Water Vapor - Water vapor regulates air temperature because it absorbs solar radiation.

6. The Earth's atmosphere is made up into four main layers; each with their own characteristics. Theses layers make up the vertical structure of the atmosphere. The most common layer, the troposphere, is the one that contains the air that is utilized on the Earth's surface. The other layers in order from closest to furthest away are the stratosphere, mesosphere, and the thermosphere. The exosphere is the upper most layer of the Earth's atmosphere and gradually fades away into space. Air in the exosphere is extremely thin. Structure of the atmosphere

7. Different Layers of the Atmosphere Troposphere  Earth’s troposphere extends from Earth’s surface to, on average, about 12 kilometers (7.5 miles) in height, with its height lower at Earth’s poles and higher at the equator. Stratosphere Located between approximately 12 and 50 kilometers (7.5 and 31 miles) above Earth’s surface, the stratosphere is perhaps best known as home to Earth’s ozone layer, which protects us from the Sun’s harmful ultraviolet radiation. Mesosphere Located between about 50 and 80 kilometers (31 and 50 miles) above Earth’s surface, the mesosphere gets progressively colder with altitude. Thermosphere  Located between about 80 and 700 kilometers (50 and 440 miles) above Earth’s surface is the thermosphere, whose lowest part contains the ionosphere. Exosphere Located between about 700 and 10,000 kilometers (440 and 6,200 miles) above Earth’s surface, the exosphere is the highest layer of Earth’s atmosphere and, at its top, merges with the solar wind. 

8. Chemical Reaction in the different layer of the atmosphere

9. Chemical Reaction in the different layer of the atmosphere  Troposphere  All organic compounds, carbon monoxide, CO, methane, CH4, and most nitrogen- and sulfur-containing species react with the hydroxyl radical in the atmosphere. Stratosphere In the stratosphere, ultraviolet light reacts with O2 molecules to form atomic oxygen. Atomic oxygen then reacts with an O2 molecule to produce ozone (O3). Mesosphere  Iron, magnesium, calcium, sodium, and potassium. Thermosphere  Atomic oxygen (O), atomic nitrogen (N), and helium (He Exosphere  The gas particles that make up this layer are extremely spread ou

10. Greenhouse gases, Ozone depletion and Air pollution

11. Greenhouse Gases: The Foundation of Climate Change Greenhouses are components of the Earth’s atmosphere that trap heat, leading to greenhouse effect. The primary greenhouse gases are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and fluorinated gases. These gases are emitted through various human activities, including burning fossil fuel, deforestation, and industrial processes. The increased concentration of greenhouse gases in the atmosphere traps more heats, leading to a warming planet and various consequence, including: This response will examine the complex relationship between greenhouse gases and air pollution, highlighting their shared causes, individual impact, and interconnected consequences for human health and environment. The Interconnected Threats of Greenhouse gases, Ozone Depletion, and Air Pollution Rising global temperatures: This causes more extreme weather events, such as heatwaves droughts, floods and storms.  Sea level rise: Melting glaciers and ice sheets contribute to rising sea levels, threatening coastal communities and ecosystem. Ocean acidification: Increased CO2 absorption by the ocean leads to acidfication, harming marine life and ecosystem.

12. Ozone Depletion: A Hole in Our Protective Shield The ozone layer in the stratosphere protects Earth from harmful Ultraviolet (UV) radiation from the sun. Ozone depletion occurs when certain chemicals, known as ozone-depleting substance (ODS), react with ozone molecules, breaking them down. The most significant ODS are Chlorofluorocarbon (CFCs), which were widely used in refrigerants, aerosols, and other products. The consequence of ozone depletion are severe: Increased UV radiation: This can lead to skin cancer, cataracts, and damage to plants and marine life. Disruption of atmospheric chemistry: Ozone depletion affects the balance of chemical reactions in the stratosphere, potentially impacting other atmospheric processes.

13. Air Pollution : A Local and Global Threat Air pollution refers to the presence of harmful substance in the air, including gases, particulate mater, and biological agents. Air pollution can be caused by both human activities (anthropogenic source) and natural phenomena (natural source). Major source of air pollution includes: Combustion of fossil fuel: Burning coal, oil, and natural gas for energy production and transportation releases pollutants such as CO2, sulfur dioxide (SO2), nitrogen oxides (NOx), and particulate matter. Industrial processes: Manufacturing, mining, and other industrial activities can releasa various pollutant into the air. Agricultural activities: Livestock farming fertilizer use, and crop burning contribute to air pollution, releasing gases like methane and ammonia.

14. The health and environmental impacts of the air pollution are significant: Respiratory illness: Air pollution can trigger asthma attacks, bronchitis, and other respiratory problems. Cardiovascular disease: Exposure to air pollution can increase the risk of heart attacks, strokes, and other cardiovascular problems. Cancer: Some air pollutants are known carcinogens, increasing the risk of lung cancer and other cancers. Acid rain: Sulfur dioxide and nitrogen oxides released from fossil fuel combustion can react with water vapor in the atmosphere to form sulfuric and nitric acid, which fall to the ground as acid rain. Acid rain damages forests, lakes and buildings. Climate change: Many air pollutants including greenhouse gases contribute to climate change.

15. Monitoring and analysis of the atmospheric pollutants

16. Monitoring and analyzing atmospheric pollutants are essential for understanding the state of air quality, identifying pollution sources, and developing effective mitigation strategies. This exploration delves into the various methods employed for monitoring and analyzing atmospheric pollutants, highlighting their importance in environmental management. Methods for Monitoring Atmospheric Pollutants Monitoring atmospheric pollutants involves collecting and analyzing air samples to determine the concentration of various pollutants. Several methods are employed, each with its advantages and limitations: 1. Passive Monitoring: Diffusion Tubes: These tubes absorb specific pollutants from the ambient air over a period of time (typically 2-4 weeks). 2. Active (Semi-Automatic) Sampling: Air Samplers: These devices actively draw air through a filter for a set period of time (e.g., one filter per day). 3. Automatic Point Monitoring: Continuous Analyzers: These instruments continuously monitor the concentration of specific pollutants in the ambient air. 4. Photochemical and Optical Sensor Systems: Portable Monitors: These devices use optical or electrochemical sensors to continuously monitor a range of pollutants. 5. Remote Optical / Long-Path Monitoring: LIDAR (Light Detection and Ranging): This technique uses lasers to measure the concentration of pollutants in the atmosphere over long distances

17. Importance of Monitoring and Analysis Monitoring and analyzing atmospheric pollutants are crucial for various reasons: - Assessing Air Quality: Monitoring data provides a clear picture of the current air quality and identifies areas where pollution levels exceed acceptable limits. - Identifying Pollution Sources: By analyzing the composition of pollutants and their spatial distribution, it is possible to pinpoint the sources of pollution. - Evaluating Mitigation Strategies: Monitoring data helps to evaluate the effectiveness of pollution control measures and identify areas where improvements are needed. - Protecting Public Health: Monitoring data informs public health officials about potential health risks associated with air pollution and allows them to implement appropriate measures to protect public health. - Supporting Environmental Policy: Monitoring data provides evidence to support environmental regulations and policies aimed at reducing air pollution.

18. THANK YOU