Ozone exists in two layers of the atmosphere - the troposphere and stratosphere. Stratospheric ozone protects life on Earth by absorbing harmful UV radiation from the sun. Chlorofluorocarbons and other ozone depleting substances released chemicals that destroyed stratospheric ozone, causing thinning of the ozone layer. Thinning of the ozone layer allows more UV radiation to reach the Earth's surface, increasing health risks like skin cancer as well as risks to plants, animals, and ecosystems. International agreements like the Montreal Protocol aimed to phase out ozone depleting substances and allow recovery of the ozone layer.
This presentation is about Ozone Layer and chemicals known to cause its depletion.
It also covers information about Ozone Hole and Correlation between Ozone depletion and skin diseases due to Ultra Violet light.It also contains no. of ways to limit ozone deterioration.
The term precipitation is also used to refer all forms of falling moisture viz., rainfall, snowfall, sleet, hail etc. Rainfall occurs in the form of a pattern. Atmospheric Precipitation is a wonderful process for the whole globe to use. This module explains it in general.
Climate change is both a development issue and an environmental issue. Developing countries are more vulnerable to climate change than rich countries. CC may be limited to a specific region, or it may occur across the whole Earth.
It can be caused by recurring and cyclical climate patterns.
The causes of climate change are many. There is a need to understand these factors for reducing the effects.
This presentation is about Ozone Layer and chemicals known to cause its depletion.
It also covers information about Ozone Hole and Correlation between Ozone depletion and skin diseases due to Ultra Violet light.It also contains no. of ways to limit ozone deterioration.
The term precipitation is also used to refer all forms of falling moisture viz., rainfall, snowfall, sleet, hail etc. Rainfall occurs in the form of a pattern. Atmospheric Precipitation is a wonderful process for the whole globe to use. This module explains it in general.
Climate change is both a development issue and an environmental issue. Developing countries are more vulnerable to climate change than rich countries. CC may be limited to a specific region, or it may occur across the whole Earth.
It can be caused by recurring and cyclical climate patterns.
The causes of climate change are many. There is a need to understand these factors for reducing the effects.
The Earth’s climate is changing. Temperatures are rising, snow and rainfall patterns are shifting, and more extreme climate events—like heavy rainstorms and record-high temperatures, are already taking place. One important way to track and communicate the causes and effects of climate change is
through the use of indicators. An indicator represents the state or trend of certain environmental or societal conditions over a given area and a specified period of time. This lesson highlights all those indicators for a better understanding of climate change.
Meteorological observations are made for a variety of reasons. They are used for the real-time preparation of weather charts and maps, for weather forecasts and severe weather warnings, for the study of climate, and for local weather-dependent operations. This module highlights all related details.
The density and distribution of climatological stations to be established in a land network within a given area depend on the meteorological elements to be observed, the topography and land use in the area, and the requirements for information about the specific climatic elements concerned. This module highlights all these aspects.
Weather forecasting is the prediction of the state of the atmosphere for a given location using the application of science and technology. This includes temperature, rain, cloudiness, wind speed, and humidity. Weather warnings are a special kind of short-range forecast carried out for the protection of human life. This module explains the details of weather forecasting.
Adaptation to global change must include prudent management of groundwater as a renewable, but slow-feedback resource in most cases. Groundwater storage is already over-tapped in many regions, yet available subsurface storage may be a key to meeting the combined demands of agriculture, industry, municipal and domestic water supply, and ecosystems during times of shortage.
Drought refers to a prolonged period of abnormally low rainfall, leading to a shortage of water. A drought can last for several months or years. Sometimes, droughts are declared for a full district for a few years.
It can have a substantial impact on the ecosystem and agriculture of the affected region and harm to the local life and economy. This module highlights the basics of climatic drought.
The climate of a region is ultimately determined by the radiation energy of the sun, and its distribution and temporal fluctuations. The long-term state of the atmosphere is a function of a variety of interacting elements. They are: Solar radiation, Air masses, Pressure systems (and cyclone belts),Ocean Currents, and topography.
Map is a drawn or printed representation of the physical features of the Earth.
It is the best tool to show, understand and analyse the features of an area. Cartography is the art and science of making maps. This module highlights many information on maps, types and their uses.
To aid in understanding many complex interactions, scientists often build mathematical models that represent simple climate systems. This module highlights the fundamentals of climate models.
Research is a systematic inquiry to describe, explain, predict and control the observed phenomenon. Research is a structured inquiry that utilizes acceptable scientific methodology to solve problems and create new knowledge that is generally applicable.
Climate data can provide a great deal of information about the atmospheric environment that impacts almost all aspects of human endeavour. This module explains the importance of climate data, its storage, security, applications and other aspects, in a nutshell.
Ozone is the one and only layer to protect our earth from harmful UV radiation. There are a lot of initiatives taken by many countries to save the ozone layer. Ozone depletion is nowadays one of the hot topics in conferences and seminars. In this presentation, I have briefed on the cause and side effects of ozone depletion. The students from school to master's may take advantage of this presentation
This is my PPT presented during my M.Sc Environmental Science Course at Department of Environmental Science, Dr. Babasaheb Ambedkar Marathwada University, Aurangabad, Maharashtra, India.
Role of ozone in environment –
Ozone layer –
Ozone depleting gases –
Green House Effect –
Radioactive effects of Greenhouse gases –
The Hydrological cycle –
Green House Gases and Global Warming –
Carbon Cycle.
Ozone is a naturally occurring molecule made up of three oxygen atoms. It has the chemical formula O3.
The word ‘ozone’ is derived from the Greek word óζειν which means “to smell”. Its strong smell allows scientists to detect it in low amounts.
Ozone is found in different levels of the earth’s atmosphere.
About 90% of ozone in the atmosphere is concentrated between 15 and 30 kilometres above the earth's surface (stratospheric ozone).
At this level it provides a protective shield from the sun, we think of this as good ozone.
It is also found at ground level in lower concentrations (tropospheric ozone).
Here ozone is a pollutant that is a key part of smog over cities and we think of it as bad ozone.
Atmospheric data demonstrates that ozone depleting substances are destroying ozone in the stratosphere and thinning the earth’s ozone layer.
Ozone depleting substances are chemicals that include -
chlorofluorocarbons (CFCs); nontoxic, nonflammable chemicals containing atoms of carbon, chlorine, and fluorine.
halons, group of organohalogen compounds containing bromine and fluorine and one or two carbons.
carbon tetrachloride (CCl4),
methyl chloroform (CH3CCl3),
Hydro-bromo-fluoro-carbons (HBFCs),
Hydro-chloro-fluoro-carbons (HCFCs),
methyl bromide (CH3Br) and
bromochloromethane (CH2BrCl).
They deplete the ozone layer by releasing chlorine and bromine atoms into the stratosphere, which destroy ozone molecules.
These and other ozone depleting substances also contribute, to varying extents, to global warming
hi everyone it is the most usefull of our some solution of routine life like what is responsibility of our envoronment and atmosphere...so see the ppt and know the problem,solution and many more future of deplating our ozone layer.......
This slides includes all the topics about the ozone layer, ozone depletion, causes and effects. the significant of ozone layer.
This slide emphasize the purpose of ozone layer in our daily living.
E-content is a Comprehensive package of teaching material put into hypermedia format. Hypermedia is multimedia with internet deplorability. E-content can not be created by a teaching faculty alone . It needs the role of teacher, Video editor, production assistants, web developers (HTML 5 or Adobe captivate, etc). Analyze the learner needs and goals of the instructional material development, development of a delivery system and content, pilot study of the material developed, implementation, evaluating, refining the materials etc. In designing and development of E-content we have to adopt one of the instructional design models based on our requirements.
Pedagogy is the most commonly understood approach to teaching. It refers to the theory and practice of learning. Pedagogy is often described as the act of teaching. Pedagogy has little variations between traditional teaching and online teaching. Online teaching pedagogy is a method of effective teaching practice specifically developed for teaching via the internet. It has a set of prescribed methods, strategies, and practices for teaching academic subjects in an online (or blended) environment, where students are in a physical location separate from the faculty member.
Technology has changed the possibilities within teaching and learning. Classes, which prior to the digital era were restricted to lectures, talks, and physical objects, no longer have to be designed in that manner. Training in a synchronous virtual classroom can only be successful with the active participation and engagement of the learners. Explore the Virtual Classroom’s features and see how they can support and enhance your tutoring style.
• The monitoring and evaluation of the institutional processes require a carefully structured system of internal and external review. The NAAC expects the Institutions to undertake continuous Academic and Administrative Audits (AAA). This presentation is intended to serve as advisory to all accredited HEIs who volunteer to undertake AAA. The pros and cons of this process are also highlighted. Academic and Administrative Audit is the process of evaluating the efficiency and effectiveness of the administrative procedure. It includes assessment of policies, strategies & functions of the various administrative departments, control of the overall administrative system, etc. This checklist gives an overview what the audit committee members may look into while visiting an institution for this purpose. It invariably follows the Quality Indicators Framework prescribed by Accreditation Council in India.
• The monitoring and evaluation of the institutional processes require a carefully structured system of internal and external review. The NAAC expects the Institutions to undertake continuous Academic and Administrative Audits (AAA). This presentation is intended to serve as advisory to all accredited HEIs who volunteer to undertake AAA.
Chemical analysis data of water samples can not be used directly for understanding. They are to be used for various calculations in order to determine the quality parameters that have a lot of significances. A. Balasubramanian and D. Nagaraju, of the Department of Studies in Earth Science, Centre for Advanced Studies, University of Mysore, Mysore-570006, Karnataka, India have recently brought out a software and its application manual as a good book for reference and execution. The Name of the software is WATCHIT meaning Water Chemistry Interpretation Techniques. This software computes more than 100 parameters pertaining to water quality interpretations. The software follows its own method of approach to determine the required results. Systems International Units are used. Limited input parameters are required. This is suitable for all scientific research, government water quality data interpretations and for understanding the quality of water before using it.
Water conservation refers to reducing the usage of water and recycling of waste water for different purposes like domestic usage, industries, agriculture etc. This technical article highlights most of the popular methods of water conservation. A special note on rainwater harvesting is also provided.
This module gives an overview of general applications of current hydrogeological aspects. It is for the basic understanding of students and research scholars.
Climate Extreme (extreme weather or climate event) refers to the occurrence of a value of a weather or climate variable above (or below) a threshold value near the upper (or lower) ends of the range of observed values of the variable. Extreme weather and climate events, interacting with exposed and vulnerable human and natural systems, can lead to disasters.
WATER RESOURCES PLANNING AND MANAGEMENT POSSIBILITIES IN CHAMARAJANAGAR TALUK...Prof. A.Balasubramanian
Any unplanned development and utilization of water resources with result in water scarcity. In many parts of the developing world. Such a situation exists. In order to do proper planning and
management of water resources, it is necessary to conduct detailed analyses of the factors, which influence the water availability and its uses. In the present study, a comprehensive analysis have been undertaken for proper utilization of water resources in Chamarajanagar Taluk, which has been identified as one of the drought hit districts of Karnataka, in India. The factors analysed in this work are, surface and groundwater availability, land use, cropping pattern, recharge potential of soils and the rainfall pattern in typical areas of Taluk. It is observed that the problem of water scarcity is mainly due to the lack of irrigation planning and management. Hence, a
modified cropping pattern is suggested by taking into consideration of all available water resources and other conditions.
In broad terms, cultural geography examines the cultural values, practices, discursive and material expressions and artefacts of people, the cultural diversity and plurality of society.
It also emphasizes on how cultures are distributed over space, how places and identities are produced, how people make sense of places and build senses of place, and how people produce and communicate knowledge and meaning.
Minerals are formed by changes in chemical energy in systems which contain one fluid or vapor phase. In nature, minerals are formed by crystallisation or precipitation from concentrated solutions. These solutions are called as ore-bearing fluids. Ore-bearing fluids are characterised by high concentration of certain metallic or other elements.
Fluids are the most effective agents for the transport of material in the mantle and the Earth's crust.
Soils are complex mixers forming the skin of the earth's surface. Soil is a dynamic layer in which many complex chemical, physical and biological activities are going on constantly. Soils become adjusted to conditions of climate, landform and vegetation, and will change internally when those controlling conditions change. Soils are products of weathering. Soils play a dominant role in earth's geomorphic processes in a cyclic manner. The characteristics of soils are very essential for several reasons. This module highlights these characteristics.
GIS TECHNIQUES IN WATER RESOURCES PLANNING AND MANAGEMENT IN CHAMARAJANAGAR ...Prof. A.Balasubramanian
The over-exploitation and contamination of groundwater continue to threaten the long-term sustainability of our precious water resources, in spite of the best efforts made by various agencies.
This has many serious implications to the economic development of a country like India. Lack of
judicious planning and integration of environmental consideration to ground water development
projects are primarily responsible for such a state of affair in the ground water sector. Geographical Information Systems could be of immense help in planning sustainable ground water management strategies, especially in hard rock areas with limited ground water potential. Data collected from
Satellite Imagery and through field investigations have been integrated, on a GIS platform, for demarcation and prioritization of areas suitable for ground water development and ground water augmentation. An attempt has also been made to assess the vulnerability of the area to ground water
contamination. This paper demonstrates the utility of GIS in planning judicious management of ground water resources in a typical hard rock area of Chamarajanagar Taluk, Karnataka, state India.
Nanobiomaterials are very effective components for several biomedical and pharmaceutical studies. Among the metallic, organic, ceramic and polymeric nanomaterials, metallic nanomaterials have shown certain prominent biomedical applications. Enormous works have been done to synthesize, analyse and administer the metallic nanoparticles for various kinds of medical and therapeutic applications, during the last forty years. In these analyses, the prominent biomedical applications of ten metallic nanobiomaterials have been reviewed from various sources and works. It has been found that almost nine of them are used in a very wide spectrum of medical and theranostic applications.
A variety of Nano-biomaterials are synthesised, characterised and tested to find out their potentialities by global scientific communities, during the last three decades. Among those, nanostructured ceramics, cements and coatings are being considered for major use in orthopaedic, dental and other medical applications. The development of novel biocompatible ceramic materials with improved biomedical functions is at the forefront of health-related applications, all over the world. Understanding of the potential biomedical applications of ceramic nanomaterials will provide a major insight into the future developments. This study reviews and enlists the prominent potential biomedical applications of ceramic nanomaterials, like Calcium Phosphate (CaP), Tri-Calcium Phosphate (TCP), Hydroxy-Apatite(HAP), TCP+HAP, Si substituted HAP, Calcium Sulphate and Carbonate, Bioactive Glasses, Bioactive Glass Ceramics, Titania-Based Ceramics, Zirconia Ceramics, Alumina Ceramcis and Ceramic Polymer Composites.
The present forest and tree cover of the country is 78.37 million ha in 2007 which is 23.84% of the geographical areas and it includes 2.82% tree cover. This becomes 25.25%, if the areas above tree line i.e., 4000m are excluded from the total geographical area. The forest cover is classified into 3 canopy density classes.
1. Very Dense Forest (VDF) with canopy density more than 70%
2. Moderately Dense Forest (MDF) with Canopy density between 40-70% and
3. Open Forest (OF) with Canopy density between 10-40%
The entire country was fully analysed and mapped for identifying the wastelands. Among all the states, the districts which have more than 15% area under wasteland were identified for detailed mapping. In order to assess the nature and propose of rejuvenating the wastelands, a common classification system has been adopted.
WRI’s brand new “Food Service Playbook for Promoting Sustainable Food Choices” gives food service operators the very latest strategies for creating dining environments that empower consumers to choose sustainable, plant-rich dishes. This research builds off our first guide for food service, now with industry experience and insights from nearly 350 academic trials.
Characterization and the Kinetics of drying at the drying oven and with micro...Open Access Research Paper
The objective of this work is to contribute to valorization de Nephelium lappaceum by the characterization of kinetics of drying of seeds of Nephelium lappaceum. The seeds were dehydrated until a constant mass respectively in a drying oven and a microwawe oven. The temperatures and the powers of drying are respectively: 50, 60 and 70°C and 140, 280 and 420 W. The results show that the curves of drying of seeds of Nephelium lappaceum do not present a phase of constant kinetics. The coefficients of diffusion vary between 2.09.10-8 to 2.98. 10-8m-2/s in the interval of 50°C at 70°C and between 4.83×10-07 at 9.04×10-07 m-8/s for the powers going of 140 W with 420 W the relation between Arrhenius and a value of energy of activation of 16.49 kJ. mol-1 expressed the effect of the temperature on effective diffusivity.
Artificial Reefs by Kuddle Life Foundation - May 2024punit537210
Situated in Pondicherry, India, Kuddle Life Foundation is a charitable, non-profit and non-governmental organization (NGO) dedicated to improving the living standards of coastal communities and simultaneously placing a strong emphasis on the protection of marine ecosystems.
One of the key areas we work in is Artificial Reefs. This presentation captures our journey so far and our learnings. We hope you get as excited about marine conservation and artificial reefs as we are.
Please visit our website: https://kuddlelife.org
Our Instagram channel:
@kuddlelifefoundation
Our Linkedin Page:
https://www.linkedin.com/company/kuddlelifefoundation/
and write to us if you have any questions:
info@kuddlelife.org
"Understanding the Carbon Cycle: Processes, Human Impacts, and Strategies for...MMariSelvam4
The carbon cycle is a critical component of Earth's environmental system, governing the movement and transformation of carbon through various reservoirs, including the atmosphere, oceans, soil, and living organisms. This complex cycle involves several key processes such as photosynthesis, respiration, decomposition, and carbon sequestration, each contributing to the regulation of carbon levels on the planet.
Human activities, particularly fossil fuel combustion and deforestation, have significantly altered the natural carbon cycle, leading to increased atmospheric carbon dioxide concentrations and driving climate change. Understanding the intricacies of the carbon cycle is essential for assessing the impacts of these changes and developing effective mitigation strategies.
By studying the carbon cycle, scientists can identify carbon sources and sinks, measure carbon fluxes, and predict future trends. This knowledge is crucial for crafting policies aimed at reducing carbon emissions, enhancing carbon storage, and promoting sustainable practices. The carbon cycle's interplay with climate systems, ecosystems, and human activities underscores its importance in maintaining a stable and healthy planet.
In-depth exploration of the carbon cycle reveals the delicate balance required to sustain life and the urgent need to address anthropogenic influences. Through research, education, and policy, we can work towards restoring equilibrium in the carbon cycle and ensuring a sustainable future for generations to come.
Diabetes is a rapidly and serious health problem in Pakistan. This chronic condition is associated with serious long-term complications, including higher risk of heart disease and stroke. Aggressive treatment of hypertension and hyperlipideamia can result in a substantial reduction in cardiovascular events in patients with diabetes 1. Consequently pharmacist-led diabetes cardiovascular risk (DCVR) clinics have been established in both primary and secondary care sites in NHS Lothian during the past five years. An audit of the pharmaceutical care delivery at the clinics was conducted in order to evaluate practice and to standardize the pharmacists’ documentation of outcomes. Pharmaceutical care issues (PCI) and patient details were collected both prospectively and retrospectively from three DCVR clinics. The PCI`s were categorized according to a triangularised system consisting of multiple categories. These were ‘checks’, ‘changes’ (‘change in drug therapy process’ and ‘change in drug therapy’), ‘drug therapy problems’ and ‘quality assurance descriptors’ (‘timer perspective’ and ‘degree of change’). A verified medication assessment tool (MAT) for patients with chronic cardiovascular disease was applied to the patients from one of the clinics. The tool was used to quantify PCI`s and pharmacist actions that were centered on implementing or enforcing clinical guideline standards. A database was developed to be used as an assessment tool and to standardize the documentation of achievement of outcomes. Feedback on the audit of the pharmaceutical care delivery and the database was received from the DCVR clinic pharmacist at a focus group meeting.
Natural farming @ Dr. Siddhartha S. Jena.pptxsidjena70
A brief about organic farming/ Natural farming/ Zero budget natural farming/ Subash Palekar Natural farming which keeps us and environment safe and healthy. Next gen Agricultural practices of chemical free farming.
Willie Nelson Net Worth: A Journey Through Music, Movies, and Business Venturesgreendigital
Willie Nelson is a name that resonates within the world of music and entertainment. Known for his unique voice, and masterful guitar skills. and an extraordinary career spanning several decades. Nelson has become a legend in the country music scene. But, his influence extends far beyond the realm of music. with ventures in acting, writing, activism, and business. This comprehensive article delves into Willie Nelson net worth. exploring the various facets of his career that have contributed to his large fortune.
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Introduction
Willie Nelson net worth is a testament to his enduring influence and success in many fields. Born on April 29, 1933, in Abbott, Texas. Nelson's journey from a humble beginning to becoming one of the most iconic figures in American music is nothing short of inspirational. His net worth, which estimated to be around $25 million as of 2024. reflects a career that is as diverse as it is prolific.
Early Life and Musical Beginnings
Humble Origins
Willie Hugh Nelson was born during the Great Depression. a time of significant economic hardship in the United States. Raised by his grandparents. Nelson found solace and inspiration in music from an early age. His grandmother taught him to play the guitar. setting the stage for what would become an illustrious career.
First Steps in Music
Nelson's initial foray into the music industry was fraught with challenges. He moved to Nashville, Tennessee, to pursue his dreams, but success did not come . Working as a songwriter, Nelson penned hits for other artists. which helped him gain a foothold in the competitive music scene. His songwriting skills contributed to his early earnings. laying the foundation for his net worth.
Rise to Stardom
Breakthrough Albums
The 1970s marked a turning point in Willie Nelson's career. His albums "Shotgun Willie" (1973), "Red Headed Stranger" (1975). and "Stardust" (1978) received critical acclaim and commercial success. These albums not only solidified his position in the country music genre. but also introduced his music to a broader audience. The success of these albums played a crucial role in boosting Willie Nelson net worth.
Iconic Songs
Willie Nelson net worth is also attributed to his extensive catalog of hit songs. Tracks like "Blue Eyes Crying in the Rain," "On the Road Again," and "Always on My Mind" have become timeless classics. These songs have not only earned Nelson large royalties but have also ensured his continued relevance in the music industry.
Acting and Film Career
Hollywood Ventures
In addition to his music career, Willie Nelson has also made a mark in Hollywood. His distinctive personality and on-screen presence have landed him roles in several films and television shows. Notable appearances include roles in "The Electric Horseman" (1979), "Honeysuckle Rose" (1980), and "Barbarosa" (1982). These acting gigs have added a significant amount to Willie Nelson net worth.
Television Appearances
Nelson's char
Micro RNA genes and their likely influence in rice (Oryza sativa L.) dynamic ...Open Access Research Paper
Micro RNAs (miRNAs) are small non-coding RNAs molecules having approximately 18-25 nucleotides, they are present in both plants and animals genomes. MiRNAs have diverse spatial expression patterns and regulate various developmental metabolisms, stress responses and other physiological processes. The dynamic gene expression playing major roles in phenotypic differences in organisms are believed to be controlled by miRNAs. Mutations in regions of regulatory factors, such as miRNA genes or transcription factors (TF) necessitated by dynamic environmental factors or pathogen infections, have tremendous effects on structure and expression of genes. The resultant novel gene products presents potential explanations for constant evolving desirable traits that have long been bred using conventional means, biotechnology or genetic engineering. Rice grain quality, yield, disease tolerance, climate-resilience and palatability properties are not exceptional to miRN Asmutations effects. There are new insights courtesy of high-throughput sequencing and improved proteomic techniques that organisms’ complexity and adaptations are highly contributed by miRNAs containing regulatory networks. This article aims to expound on how rice miRNAs could be driving evolution of traits and highlight the latest miRNA research progress. Moreover, the review accentuates miRNAs grey areas to be addressed and gives recommendations for further studies.
Micro RNA genes and their likely influence in rice (Oryza sativa L.) dynamic ...
Atmospheric ozone and its depletion
1. 1
ATMOSPHERIC OZONE AND ITS
DEPLETION
by
Prof. A. Balasubramanian
Centre for Advanced Studies in Earth Science
University of Mysore, India
2. 2
Ozone is a form of oxygen:
Ozone (O3) is formed by the combination of
three oxygen atoms. Normal oxygen which we
breathe is colourless and odourless.
Ozone is much less common than normal
oxygen. Out of 10 million air molecules, about
2 million are normal oxygen, but only 3 are
ozone.
3. 3
An unstable gas with a strong and irritating odor
(which explains its name), ozone is corrosive, a
strong oxidant and very toxic.
For all of these reasons it absolutely unsuitable
to sustain life. Ozone is generally produced by
generating high-power electrical discharges in
air or in oxygen.
Naturally found in the upper layers of the
atmosphere.
4. 4
In Liquid phase Ozone is fairly unstable in a
watery solution; its half-life in water is about 20
minutes.
In air, ozone has a half-life of 12 hours, which
makes the stability of ozone in air superior.
Liquid ozone has a deep blue, almost black,
colour, and is opaque in layers exceeding 2 mm.
in thickness.
5. 5
Discovery :
It was first discovered in the 1830s by the
German scientist Christian Schönbein.
He identified a new compound in laboratory
experiments using oxygen, and named the
molecule “ozein,” meaning “to smell” in Greek.
In 1881, John Hartley experimented with ozone
and found that it was strongly absorbing the
ultraviolet light.
6. 6
The oxygen we breathe is in the form of oxygen
molecules (O2) - two atoms of oxygen bound
together.
Physical Properties of Ozone:
Ozone absorbs radiation strongly in the
ultraviolet region of the atmospheric spectrum
between 220-290 nm.
7. 7
This protects the Earth and its inhabitants from
the harmful ultraviolet radiation of the Sun.
Without this protective layer, more ultraviolet
radiation would reach the surface of the Earth
and cause damage to plant, animal and human
life.
Molecular weight : 47.998 g/mol. Melting
point : -193 °C.
Liquid density (1.013 bar at boiling point) :
1349.08 kg/m3
.
9. 9
Gas density (1.013 bar and 0 °C (32 °F)) : 2.154
kg/m3
. Specific gravity : 1.612.
Pure ozone is a blue gas, with a strong irritating
smell.
When inhaled, it causes headache and nausea.
In smaller proportions it smells pleasant.
It is about 1.5 times heavier than air and has a
vapor density of 24, corresponding to the
formula O3.
10. 10
It is more soluble than oxygen in water, about
49% by volume at 0°C.
It gets liquefied to a deep blue colour liquid,
when cooled in liquid air.
It boils at 161.2 K and solidifies to violet-black
crystals, which melt at 80.6 K.
It dissolves readily in turpentine oil and acetic
acid.
The Chemical Properties of Ozone are very
unique. Let us learn some of them, here.
11. 11
Decomposition:
Ozone is an unstable compound.
Pure ozone decomposes explosively, while
ozonised oxygen decomposes slowly at room
temperature.
The decomposition is accelerated by the
presence of manganese dioxide, platinum black
and copper oxide etc.
12. 12
Bleaching agent :
Due to the oxidizing action of ozone, it acts as a
mild bleaching agent as well as a sterilizing
agent. It acts as a bleaching agent for vegetable
coloring matter.
Oxidizing property:
Ozone acts as a powerful oxidizing agent due to
the reaction, .
13. 13
The nascent oxygen formed due to its
decomposition is responsible for the oxidation
of a number of substances.
Reaction with mercury:
When ozone is passed through mercury, it loses
its meniscus and sticks to the glass due to the
formation of mercurous oxide.
This is called tailing of mercury.
14. 14
Uses of ozone:
Ozone is used for air purification at the crowded
places like cinema halls and tunnel railways.
Due to its strong oxidizing power it also
destroys the foul smell in slaughter houses. In
sterilizing drinking water by oxidizing all germs
and bacteria.
For preservation of meat in cold storages.
15. 15
For bleaching delicate fabrics such as silk,
ivory, oils, starch and wax. It helps to locate a
double bond in any unsaturated organic
compound by ozonolysis.
Pharmaceuticals:
Ozone is used in chemical synthesis and for
treatment of wastewater.
16. 16
Food and beverage:
Ozone's very strong oxidation properties are
sufficient to kill micro-organisms on food
stuffs. Further, ozone short shelf life prevents
products from any residual contamination.
These properties have been successfully used in
fish farming water treatment, greenhouse
nutritive solution recycling and sanitation of
food products.
17. 17
Pulp and paper:
Environment-friendly paper pulp bleaching.
Ozone is produced from oxygen at the point of
use for stability reasons.
Ozone is used under variable concentrations for
pulp bleaching (ECF or TCF Pulps), to reduce
the residual fluorescence coming from the
optical whiteners of the waste papers and for
treatment of specific effluents.
18. 18
Environmental control:
Ozone decreases 'hard' COD (Chemical Oxygen
Demand)
Occurrence and Distribution :
Ozone also occurs in very small amounts in the
lowest few kilometres of the atmosphere, a
region known as the troposphere.
19. 19
It is produced at ground level through a reaction
between sunlight and volatile organic
compounds (VOCs) and nitrogen oxides (NOx),
some of which are produced by human
activities such as driving cars.
Ground-level ozone is a component of urban
smog and can be harmful to human health.
20. 20
While ozone can be found through the entire
atmosphere, the greatest concentration occurs at
altitudes between 19 and 30 km above the
Earth's surface.
This band of ozone-rich air is known as the
"ozone layer".
Most ozone is produced naturally in the upper
atmosphere or stratosphere.
Ozone concentrations are highest between 19
and 23 km.
21. 21
Most of the ozone in the stratosphere is formed
over the equator where the level of sunshine
striking the Earth is greatest. It is transported by
winds towards higher latitudes.
The Two Ozone Layers :
The term “ozone layer” generally refers to a
relatively high concentration of ozone in the
stratosphere, a layer of very dry air around 15 to
35 kilometers (9 to 22 miles) above the Earth’s
surface.
22. 22
However, about 10 percent of the total ozone is
found in the troposphere, the lowest portion of
the atmosphere.
Tropospheric Ozone :
he ozone between the surface and the
tropopause forms only a fraction of the ozone
over most locations.
23. 23
Nevertheless, it absorbs solar UV more
efficiently than an equal amount of stratospheric
ozone.
This is because scattering caused by dust and
aerosols increases the distance that rays of
sunlight travel on their way to the surface.
In spite of this benefit, tropospheric ozone is
often referred to as “bad” ozone because of its
adverse effects in high concentrations.
24. 24
If the same ozone were somehow to drift into
the stratosphere, it would be called “good”
ozone.
Stratospheric Ozone:
Most references to the ozone layer mean the
ozone found in the stratosphere.
25. 25
There it forms a vaporous shield that protects
life on Earth from the lethal effects of the sun’s
UV radiation.
Hence, it has been called the Earth’s sunscreen.
Normal ozone concentration is about 300 to 350
D.U.
Stratospheric ozone depletion is so severe that
levels fall below 200 Dobson Units (D.U.), the
traditional measure of stratospheric ozone.
26. 26
Measuring Stratospheric Ozone :
Ozone in the stratosphere can be measured
directly using instruments on aircraft, rockets,
and–especially–balloons.
Many of the same kinds of sensing systems
used for measuring ozone at the surface have
been modified for these roles.
27. 27
Several kinds of optical instruments have been
developed for measuring ozone from the
surface, including the Dobson
spectrophotometer and various instruments that
use filters or diffraction gratings to measure
narrow bands of ultraviolet.
28. 28
Ozone Layer Depletion :
In the 1970s, scientists discovered that
chlorofluorocarbons (CFCs) could destroy
ozone in the stratosphere.
Compounds that contain chlorine and bromine
molecules, such as methyl chloroform, halons,
and chlorofluorocarbons (CFCs), are stable and
have atmospheric lifetimes long enough to be
transported by winds into the stratosphere.
29. 29
When these ozone-depleting substances (ODS)
break down in the atmosphere, they release
chlorine or bromine, which attack ozone.
Each chlorine or bromine atom reacts with
ozone, repeatedly combining with and breaking
apart as many as 100,000 ozone molecules
during its stratospheric life.
30. 30
CFCs, which have a long history of use as
refrigerants, solvents, foam-blowing agents and
in other applications, have been almost
completely phased out worldwide.
In addition, restrictions are now in place to
phase out hydrochlorofluorocarbons (HCFCs),
compounds used as substitutes for the more
damaging CFCs.
31. 31
A combination of low temperatures, elevated
chlorine, and bromine concentrations in the
upper stratosphere are responsible for the
destruction of ozone.
CFC's account for almost 80% of the total
depletion of ozone. Other ozone-depleting
substances (ODS), include
hydrochlorofluorocarbons (HCFCs), and
volatile organic compounds (VOCs).
32. 32
These are often found in vehicle emissions, by
products of industrial processes, refrigerants,
and aerosols.
As ozone depletes in the stratosphere, it forms a
'hole' in the layer.
This hole enables harmful ultraviolet rays to
enter the Earth's atmosphere.
33. 33
EFFECT OF OZONE LAYER DEPLETION
A. Effects on Human and Animal Health -
profound impact on human health with potential
risks of eye diseases, skin cancer and infectious
diseases.
Skin cancer:
Exposure to ultraviolet rays poses an increased
risk of developing several types of skin cancers,
including malignant melanoma, and basal and
squamous cell carcinoma.
34. 34
Eye damage:
Direct exposure to UV radiations can result in
photokeratitis (snow blindness), and cataracts.
Immune system damage:
Effects of UV rays include impairment of the
immune system. Increased exposure to UV rays
weakens the response of the immune system.
35. 35
Accelerated aging of skin:
Constant exposure to UV radiation can cause
photo allergy, which results in the outbreak of
rashes in fair-skinned people.
Other effects:
Ozone chemicals can cause difficulty in
breathing, chest pain, throat irritation, and
hamper lung functioning. UV radiation is
known to damage the cornea and lens of the
eye.
36. 36
Chronic exposure to UV-B could lead to
cataract of the cortical and posterior subcapsular
forms. UV-B radiation can adversely affect the
immune system causing a number of infectious
diseases.
In light skinned human populations, it is likely
to develop nonmelanoma skin cancer (NMSC).
Sunburn /Sun-Damaged Skin /Snow Blindness
/ Skin Cancer /Immune System Deficiencies.
37. 37
Decreases immunity-
Some species have become more vulnerable to
diseases and death . Retinal damage and
blindness in some species.
Effects on Amphibians:
Ozone depletion is listed as one of the causes
for the declining numbers of amphibian species.
Ozone depletion affects many species at every
stage of their life cycle.
38. 38
Some of the effects are :
a) Hampers growth and development in larvae.
b) Changes the behavior and habits, Causes
deformities in some species.
Effects on Marine Ecosystems:
Plankton (phytoplankton and bacterioplankton)
are threatened by increased UV radiation.
39. 39
Ultraviolet rays can influence the survival rates
of these microscopic organisms, by affecting
their orientation and mobility. This eventually
disturbs and affects the entire ecosystem.
B. Effects on Terrestrial Plants: Impact on
Plants:
In some species of plants, UV radiation can
alter the time of flowering, as well as the
number of flowers produced by a plant.
40. 40
Plant growth can be directly affected by UV-B
radiation. Despite mechanisms to reduce or
repair these effects, physiological and
developmental processes of plants are affected.
In forests and grasslands increased UV-B
radiation is likely to result in changes in species
composition (mutation) thus altering the bio-
diversity in different ecosystems.
41. 41
UV-B could also affect the plant community
indirectly resulting in changes in plant form,
secondary metabolism, etc.
C. Effects on Aquatic Ecosystems
While more than 30 percent of the world’s
animal protein for human consumption comes
from the sea alone, it is feared that increased
levels of UV exposure can have adverse
impacts on the productivity of aquatic systems.
42. 42
High levels of exposure in tropics and
subtropics may affect the distribution of
phytoplanktons which form the foundation of
aquatic food webs.
D. Effects on Bio-geo-chemical Cycles
Increased solar UV radiation could affect
terrestrial and aquatic bio-geo-chemical cycles
thus altering both sources and sinks of
greenhouse and important trace gases.
43. 43
They are carbon dioxide (CO2), carbon
monoxide (CO), carbonyl sulphide (COS), etc.
Other effects of increased UV-B radiation
include:
Changes in the production and decomposition
of plant matter;
reduction of primary production changes in the
uptake and release of important atmospheric
gases;
44. 44
reduction of bacterioplankton growth in the
upper ocean;
increased degradation of aquatic dissolved
organic matter (DOM), etc.
E. Effects on Air Quality
Reduction of stratospheric ozone and increased
penetration of UV-B radiation result in higher
photo dissociation rates of key trace gases that
control the chemical reactivity of the
troposphere.
45. 45
F. Effects on Materials - adverse effects on
synthetic polymers, naturally occurring
biopolymers and some other materials of
commercial interest.
UV-B radiation accelerates the photo
degradation rates of these materials thus
limiting their lifetimes.
46. 46
G. Effects on Climate Change
Ozone depletion and climate change are linked
in a number of ways, but ozone depletion is not
a major cause of climate change.
Atmospheric ozone has two effects on the
temperature balance of the Earth.
It absorbs solar ultraviolet radiation, which
heats the stratosphere.
47. 47
H. Effects on Ultraviolet Radiation
The depletion of the ozone layer leads to an
increase in ground-level ultraviolet radiation,
because ozone is an effective absorber of ultra-
violet radiation.
Some of this UV radiation (UV-B) is especially
effective in causing damage to living beings.
48. 48
The largest decreases in ozone during the past
15 years have been observed over Antarctica,
especially during each September and October
when the ozone hole forms.
I. Other Effects:
Ozone present in the lower atmosphere is
regarded as a pollutant and a greenhouse gas,
that can contribute to global warming and
climate change.
49. 49
How is the ozone hole related to global
warming?
Continued global warming will speed up the
process of stratospheric ozone depletion.
The depletion of the ozone increases when the
stratosphere gets colder.
Because global warming traps heat in the
troposphere, a less amount of the heat reaches
the stratosphere, making it colder.
50. 50
The greenhouse gases act as a cover or shield
for the troposphere making it warmer and
keeping the stratosphere cool.
Global warming can make ozone depletion way
worse right when it is supposed to recover in
the next century.
51. 51
International Actions :
The first international action to focus attention
on the dangers of ozone depletion in the
stratosphere and its dangerous consequences in
the long run on life on earth, was focused in
1977 when in a meeting of 32 countries held in
Washington D.C.
52. 52
Montreal Protocol In 1985 the Vienna
Convention established mechanisms for
international co-operation in research into the
ozone layer and the effects of ozone depleting
chemicals (ODCs).
1985 also marked the first discovery of the
Antarctic ozone hole.
53. 53
On the basis of the Vienna Convention, the
Montreal Protocol on Substances that Deplete
the Ozone Layer was negotiated and signed by
24 countries and by the European Economic
Community in September 1987.