The document provides an overview of Earth's atmosphere including:
- Its composition of nitrogen (78%), oxygen (21%), and trace amounts of other gases.
- It describes the layers of the atmosphere from lowest to highest - troposphere, stratosphere, mesosphere, thermosphere, and exosphere.
- Key topics covered include the nitrogen cycle, how pressure decreases with altitude, measuring pressure, atmospheric chemistry, and issues like acid rain, the greenhouse effect, and ozone depletion.
ATMOSPHERE ENVIRONMENT
PRESENTORS ::
>> Cuevas, Jennifer
>> Doble, Rogin
>> Gutierrez, Arlene
>> Marasigan, Debie Joy
>> Sibuan, Andrew
The Atmosphere Environment
This chapter discusses:
The significance of the Atmosphere
The composition of the Atmosphere
The layers of the atmosphere
The Atmospheric Circulation
Importance
Atmosphere – a thin layer of air that forms a protective covering around Earth.
It keeps Earth’s temperature in a range that can support life.
It also care for life-forms from some of the Sun’s harmful rays.
The Composition of Atmosphere
The Atmosphere** layer of gas that surrounds Earth more commonly known as “air”.
Atmosphere. How do you know its there
Is this “air” that surrounds us considered matter? Does it weigh anything? How do you know?
Think about it and decide on an answer.
Talk in groups with the person who sits by you
Be ready to tell the class what you decided and why.
Weight of the atmosphere
Gases are in the atmosphere.
They are things we learned about in the periodic table: Nitrogen, Oxygen, Carbon Dioxide, Hydrogen
It is matter! Sound can travel through it.
Even though you can’t see them, Atoms make up gases.
Are some atoms bigger than others?
Are their atomic weights all the same?
Helium vs. Carbon Dioxide
Do you think of helium as light and floating or heavy and falling?
Do you think about Carbon Dioxide as light and floating or heavy and falling….think about the gas released from dry ice… does it go up or down?
Weight of the atmosphere
Gases are in the atmosphere.
They are things we learned about in the periodic table: Nitrogen, Oxygen, Carbon Dioxide, Hydrogen
It is matter! Sound can travel through it.
Even though you can’t see them, Atoms make up gases.
Are some atoms bigger than others?
Are their atomic weights all the same?
Helium vs. Carbon Dioxide
Do you think of helium as light and floating or heavy and falling?
Do you think about Carbon Dioxide as light and floating or heavy and falling….think about the gas released from dry ice… does it go up or down?
Weight of the atmosphere
Gases are in the atmosphere.
They are things we learned about in the periodic table: Nitrogen, Oxygen, Carbon Dioxide, Hydrogen
It is matter! Sound can travel through it.
Even though you can’t see them, Atoms make up gases.
Are some atoms bigger than others?
Are their atomic weights all the same?
Helium vs. Carbon Dioxide
Do you think of helium as light and floating or heavy and falling?
Do you think about Carbon Dioxide as light and floating or heavy and falling….think about the gas released from dry ice… does it go up or down?
This presentations covers composition of air ,layers of atmosphere.If you like this presentation please give it a like .
for more interesting presentations visit my page - http://allfactsatonce.blogspot.in/
ATMOSPHERE ENVIRONMENT
PRESENTORS ::
>> Cuevas, Jennifer
>> Doble, Rogin
>> Gutierrez, Arlene
>> Marasigan, Debie Joy
>> Sibuan, Andrew
The Atmosphere Environment
This chapter discusses:
The significance of the Atmosphere
The composition of the Atmosphere
The layers of the atmosphere
The Atmospheric Circulation
Importance
Atmosphere – a thin layer of air that forms a protective covering around Earth.
It keeps Earth’s temperature in a range that can support life.
It also care for life-forms from some of the Sun’s harmful rays.
The Composition of Atmosphere
The Atmosphere** layer of gas that surrounds Earth more commonly known as “air”.
Atmosphere. How do you know its there
Is this “air” that surrounds us considered matter? Does it weigh anything? How do you know?
Think about it and decide on an answer.
Talk in groups with the person who sits by you
Be ready to tell the class what you decided and why.
Weight of the atmosphere
Gases are in the atmosphere.
They are things we learned about in the periodic table: Nitrogen, Oxygen, Carbon Dioxide, Hydrogen
It is matter! Sound can travel through it.
Even though you can’t see them, Atoms make up gases.
Are some atoms bigger than others?
Are their atomic weights all the same?
Helium vs. Carbon Dioxide
Do you think of helium as light and floating or heavy and falling?
Do you think about Carbon Dioxide as light and floating or heavy and falling….think about the gas released from dry ice… does it go up or down?
Weight of the atmosphere
Gases are in the atmosphere.
They are things we learned about in the periodic table: Nitrogen, Oxygen, Carbon Dioxide, Hydrogen
It is matter! Sound can travel through it.
Even though you can’t see them, Atoms make up gases.
Are some atoms bigger than others?
Are their atomic weights all the same?
Helium vs. Carbon Dioxide
Do you think of helium as light and floating or heavy and falling?
Do you think about Carbon Dioxide as light and floating or heavy and falling….think about the gas released from dry ice… does it go up or down?
Weight of the atmosphere
Gases are in the atmosphere.
They are things we learned about in the periodic table: Nitrogen, Oxygen, Carbon Dioxide, Hydrogen
It is matter! Sound can travel through it.
Even though you can’t see them, Atoms make up gases.
Are some atoms bigger than others?
Are their atomic weights all the same?
Helium vs. Carbon Dioxide
Do you think of helium as light and floating or heavy and falling?
Do you think about Carbon Dioxide as light and floating or heavy and falling….think about the gas released from dry ice… does it go up or down?
This presentations covers composition of air ,layers of atmosphere.If you like this presentation please give it a like .
for more interesting presentations visit my page - http://allfactsatonce.blogspot.in/
The earth is the only known planet, on which life exists. The present condition and properties of earth’s atmosphere are one of the main reasons for earth to support life. The atmosphere is the blanket of gases or vapours that surrounds the earth, and held together by the force of gravity.
The earth is the only known planet, on which life exists. The present condition and properties of earth’s atmosphere are one of the main reasons for earth to support life. The atmosphere is the blanket of gases or vapours that surrounds the earth, and held together by the force of gravity.
power point presentation in atmospheric chemistryJamaicaFiel
this will provide quick discussion on atmospheric chemistry and some other details on atmosphere including layers of the atmosphere and environmental problems in the atmosphere
Importance of Atmosphere –
Physical and chemical characteristics of Atmosphere –
Vertical structure of the atmosphere –
Composition of the atmosphere –
Temperature profile of the atmosphere –
Lapse rates –
Temperature inversion –
Effects of inversion on pollution dispersion.
Atmospheric stability
Earth’s atmosphere is a thin blanket of gases and tiny particles — together called air.
Atmosphere is the air surrounding the earth.
The Earth’s atmosphere is a mixture of gases and water vapour, and also of some amount of aerosols (dust, smoke, condensation products of vapor)
It contains life-giving gases like Oxygen for humans and animals and carbon dioxide for plants.
It envelops the earth all round and is held in place by the gravity of the earth.
It helps in stopping the ultraviolet rays harmful to the life and maintains the suitable temperature necessary for life.
Chapter 4THE ATMOSPHERE14.1 THE ATMOSPHERE4.1.1 .docxchristinemaritza
Chapter 4
THE ATMOSPHERE
1
4.1 THE ATMOSPHERE
4.1.1 INTRODUCTION
The atmosphere, the gaseous layer that surrounds the earth, formed over four billion years ago. During
the evolution of the solid earth, volcanic eruptions released gases into the developing atmosphere. Assuming
the outgasing was similar to that of modern volcanoes, the gases released included: water vapor (H2O),
carbon monoxide (CO), carbon dioxide (CO2), hydrochloric acid (HCl), methane (CH4), ammonia (NH3),
nitrogen (N2) and sulfur gases. The atmosphere was reducing because there was no free oxygen. Most of
the hydrogen and helium that outgassed would have eventually escaped into outer space due to the inability
of the earth's gravity to hold on to their small masses. There may have also been signi�cant contributions
of volatiles from the massive meteoritic bombardments known to have occurred early in the earth's history.
Water vapor in the atmosphere condensed and rained down, eventually forming lakes and oceans. The
oceans provided homes for the earliest organisms which were probably similar to cyanobacteria. Oxygen
was released into the atmosphere by these early organisms, and carbon became sequestered in sedimentary
rocks. This led to our current oxidizing atmosphere, which is mostly comprised of nitrogen (roughly 71
percent) and oxygen (roughly 28 percent). Water vapor, argon and carbon dioxide together comprise a
much smaller fraction (roughly 1 percent). The atmosphere also contains several gases in trace amounts,
such as helium, neon, methane and nitrous oxide. One very important trace gas is ozone, which absorbs
harmful UV radiation from the sun.
4.1.2 ATMOSPHERIC STRUCTURE
The earth's atmosphere extends outward to about 1,000 kilometers where it transitions to interplanetary
space. However, most of the mass of the atmosphere (greater than 99 percent) is located within the �rst
40 kilometers. The sun and the earth are the main sources of radiant energy in the atmosphere. The
sun's radiation spans the infrared, visible and ultraviolet light regions, while the earth's radiation is mostly
infrared.
The vertical temperature pro�le of the atmosphere is variable and depends upon the types of radiation
that a�ect each atmospheric layer. This, in turn, depends upon the chemical composition of that layer
(mostly involving trace gases). Based on these factors, the atmosphere can be divided into four distinct
layers: the troposphere, stratosphere, mesosphere, and thermosphere.
The troposphere is the atmospheric layer closest to the earth's surface. It extends about 8 - 16 kilometers
from the earth's surface. The thickness of the layer varies a few km according to latitude and the season of
the year. It is thicker near the equator and during the summer, and thinner near the poles and during the
1This content is available online at <http://cnx.org/content/m16687/1.2/>.
Available for free at Connexions <http://cnx.org/content/col10548/1.2>
15
16 CHAPTER 4. THE ATMOS ...
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
Nutraceutical market, scope and growth: Herbal drug technologyLokesh Patil
As consumer awareness of health and wellness rises, the nutraceutical market—which includes goods like functional meals, drinks, and dietary supplements that provide health advantages beyond basic nutrition—is growing significantly. As healthcare expenses rise, the population ages, and people want natural and preventative health solutions more and more, this industry is increasing quickly. Further driving market expansion are product formulation innovations and the use of cutting-edge technology for customized nutrition. With its worldwide reach, the nutraceutical industry is expected to keep growing and provide significant chances for research and investment in a number of categories, including vitamins, minerals, probiotics, and herbal supplements.
(May 29th, 2024) Advancements in Intravital Microscopy- Insights for Preclini...Scintica Instrumentation
Intravital microscopy (IVM) is a powerful tool utilized to study cellular behavior over time and space in vivo. Much of our understanding of cell biology has been accomplished using various in vitro and ex vivo methods; however, these studies do not necessarily reflect the natural dynamics of biological processes. Unlike traditional cell culture or fixed tissue imaging, IVM allows for the ultra-fast high-resolution imaging of cellular processes over time and space and were studied in its natural environment. Real-time visualization of biological processes in the context of an intact organism helps maintain physiological relevance and provide insights into the progression of disease, response to treatments or developmental processes.
In this webinar we give an overview of advanced applications of the IVM system in preclinical research. IVIM technology is a provider of all-in-one intravital microscopy systems and solutions optimized for in vivo imaging of live animal models at sub-micron resolution. The system’s unique features and user-friendly software enables researchers to probe fast dynamic biological processes such as immune cell tracking, cell-cell interaction as well as vascularization and tumor metastasis with exceptional detail. This webinar will also give an overview of IVM being utilized in drug development, offering a view into the intricate interaction between drugs/nanoparticles and tissues in vivo and allows for the evaluation of therapeutic intervention in a variety of tissues and organs. This interdisciplinary collaboration continues to drive the advancements of novel therapeutic strategies.
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
Slide 1: Title Slide
Extrachromosomal Inheritance
Slide 2: Introduction to Extrachromosomal Inheritance
Definition: Extrachromosomal inheritance refers to the transmission of genetic material that is not found within the nucleus.
Key Components: Involves genes located in mitochondria, chloroplasts, and plasmids.
Slide 3: Mitochondrial Inheritance
Mitochondria: Organelles responsible for energy production.
Mitochondrial DNA (mtDNA): Circular DNA molecule found in mitochondria.
Inheritance Pattern: Maternally inherited, meaning it is passed from mothers to all their offspring.
Diseases: Examples include Leber’s hereditary optic neuropathy (LHON) and mitochondrial myopathy.
Slide 4: Chloroplast Inheritance
Chloroplasts: Organelles responsible for photosynthesis in plants.
Chloroplast DNA (cpDNA): Circular DNA molecule found in chloroplasts.
Inheritance Pattern: Often maternally inherited in most plants, but can vary in some species.
Examples: Variegation in plants, where leaf color patterns are determined by chloroplast DNA.
Slide 5: Plasmid Inheritance
Plasmids: Small, circular DNA molecules found in bacteria and some eukaryotes.
Features: Can carry antibiotic resistance genes and can be transferred between cells through processes like conjugation.
Significance: Important in biotechnology for gene cloning and genetic engineering.
Slide 6: Mechanisms of Extrachromosomal Inheritance
Non-Mendelian Patterns: Do not follow Mendel’s laws of inheritance.
Cytoplasmic Segregation: During cell division, organelles like mitochondria and chloroplasts are randomly distributed to daughter cells.
Heteroplasmy: Presence of more than one type of organellar genome within a cell, leading to variation in expression.
Slide 7: Examples of Extrachromosomal Inheritance
Four O’clock Plant (Mirabilis jalapa): Shows variegated leaves due to different cpDNA in leaf cells.
Petite Mutants in Yeast: Result from mutations in mitochondrial DNA affecting respiration.
Slide 8: Importance of Extrachromosomal Inheritance
Evolution: Provides insight into the evolution of eukaryotic cells.
Medicine: Understanding mitochondrial inheritance helps in diagnosing and treating mitochondrial diseases.
Agriculture: Chloroplast inheritance can be used in plant breeding and genetic modification.
Slide 9: Recent Research and Advances
Gene Editing: Techniques like CRISPR-Cas9 are being used to edit mitochondrial and chloroplast DNA.
Therapies: Development of mitochondrial replacement therapy (MRT) for preventing mitochondrial diseases.
Slide 10: Conclusion
Summary: Extrachromosomal inheritance involves the transmission of genetic material outside the nucleus and plays a crucial role in genetics, medicine, and biotechnology.
Future Directions: Continued research and technological advancements hold promise for new treatments and applications.
Slide 11: Questions and Discussion
Invite Audience: Open the floor for any questions or further discussion on the topic.
2. CONTENT
Earth atmosphere
Composition of atmosphere
Nitrogen cycle
Pressure in atmosphere
Pressure changes with altitude
Measure pressure
Fact about Earth’s atmosphere
Atmospheric Chemistry
Troposphere
Stratosphere
Mesosphere
2
Thermosphere
Exosphere
Ionosphere
Acid Rain
Green House Effect
Ozone Depletion
3. Earth’s
atmosphere!
3
Earth’s atmosphere is a layer of gases surrounding the
planet.
The Earth is surrounded by a blanket
of air, which we call the atmosphere.
It reaches over 560 kilometers from
the surface of the Earth.
Atmosphere:
Absorbs the energy from the Sun,
Recycles water and other chemicals,
protects us from high-energy radiation and the frigid
vacuum of space.
The atmosphere protects and supports life.
4. Earth’s atmosphere
Earth’s atmosphere is made of a mixture of gases
called air.
Nitrogen gas makes up about 78% of
Earth’s atmosphere.
The second most abundant gas is
oxygen, which makes up 21% of
Earth’s atmosphere.
The third Argon (Ar, 0.9%).
Carbon Dioxide (CO2, 0.03%).
5. 5
Composition of the Atmosphere
The atmosphere is comprised of a variety of gases:
Major Constituents (99%):
Nitrogen (N): 78%
Oxygen (O2): 21%
Trace Constituents:
Argon (Ar), about 0.9%
Water vapor (H2O), up to 10000 ppmv
Carbon dioxide (CO2), 350 ppmv
Ozone (O3), near zero at the surface, up to 10
ppmv in the stratosphere
Methane (CH4), 1.7 ppmv
and others…..
ppmv = “parts per million by volume”
6. Nitrogen Cycle
> Nitrogen is important to protein
which is found in the body tissues
of all living things.
> Nitrogen is cycled through the
soil and into plants and finally
when living things die and decay.
6
7. Pressure in the
atmosphere
> Atmospheric pressure is the force per unit
area exerted into a surface by the weight of
air above that surface in the atmosphere of
earth
> The gas molecules closest to Earth’s surface
are packed together very closely.
> This means pressure is lower the higher up
you go into the atmosphere.
7
8. > At sea level, the weight
of the column of air
above a person is about
9,800 Newtons (2,200
pounds)!
> This is equal to the
weight of a small car.
Pressure in the atmosphere
8
2,200pounds=
9. Pressure changes with altitude
Pressure varies
smoothly from
the Earth's
surface to the top
of themesosphere
9
10. Measuring Pressure
> A barometer is an instrument
that measures atmospheric
pressure.
> Long ago, mercury barometers
were used Since mercury is a
poisonous liquid, aneroid
barometers are used today.
10
11. EARTH’S ATMOSPHERE
11
o Troposphere
o Stratosphere
o Mesosphere
o Thermosphere and
o Exosphere.
The exosphere gradually fades away into the realm of
interplanetary space.
Earth’s atmosphere has a series of layers, each with its
own specific traits.
Moving upward from ground level, these layers are named
12. Atmospheric Chemistry
EARTH’S
ATMOSPHERE
12
Exosphere
o1600 km; Very high Temp.,
oH2, HE, Outer Space
Thermosphere
o90-500 km; -92 to 1200 oC
Temp.,
oO2, NO+
Mesosphere
o50-90 km; -2 to -92 oC Temp,
o(Ionoshere: O+
2, O+ , NO+ , e-)
Stratosphere
o11-50 km; -56 to -2 oC Temp,
oO3 (Ozone Layer: 15 km)
Troposphere
o0-11 km; 15 to -56 oC Temp,
oN2, O2, CO2, H2O
13. Troposphere
> Lowest and thinnest layer 16 km at equator, 8 km
at poles
> 90% of the atmosphere’s mass
> Temperature decreases with altitude
6°C per kilometer
Top of troposphere averages –50°C
> Where weather occurs
> Boundary between the troposphere, and the
stratosphere is called the tropopause.
13
View of troposphere layer from an
airplane's window.
14. Stratosphere
14
The stratosphere extends from the top of the
troposphere to about 50 km (31 miles) above the
ground.
The infamous ozone layer is found within the
stratosphere.
Ozone molecules in this layer absorb high-energy
ultraviolet (UV) light from the Sun, converting
the UV energy into heat.
Unlike the troposphere, the stratosphere actually
gets warmer the higher you go!
That trend of rising temperatures with altitude
means that air in the stratosphere lacks the
turbulence and updrafts of the troposphere beneath.
Commercial passenger jets fly in the lower
stratosphere, partly because this less-turbulent layer
provides a smoother ride.
The jet stream flows near the border between the
troposphere and the stratosphere.
15. Mesosphere
15
Above the stratosphere is the mesosphere.
It extends upward to a height of about
85 km (53 miles) above our planet.
Most meteors burn up in the mesosphere.
Unlike the stratosphere, temperatures
once again grow colder as you rise up
through the mesosphere.
The coldest temperatures in Earth's
atmosphere, about -90° C (-130° F), are
found near the top of this layer.
The air in the mesosphere is far too thin to
breathe; air pressure at the bottom of the
layer is well below 1% of the pressure at sea
level, and continues dropping as you go
higher.
16. Thermosphere
16
The layer of very rare air above the mesosphere is
called the thermosphere.
High-energy X-rays and UV radiation from the
Sun are absorbed in the thermosphere, raising its
temperature to hundreds or at times thousands of
degrees.
The air in this layer is so thin that it would feel
freezing cold to us!
The thermosphere is more like outer space than a
part of the atmosphere. Many satellites actually
orbit Earth within the thermosphere!
The top of the thermosphere can be found
anywhere between 500 and 1,000 km (311 to 621
miles) above the ground. Temperatures in the
upper thermosphere can range from about 500 °C
(932 °F) to 2,000 °C (3,632 °F) or higher.
The aurora, the Northern Lights and Southern
Lights, occur in the thermosphere.
17. Place your screenshot
here
17
Although some experts consider the thermosphere
to be the uppermost layer of our atmosphere,
other consider the exosphere to be the actual
"final frontier" of Earth's gaseous envelope.
As you might imagine, the "air" in the exosphere is
very, very, very thin, making this layer even more
space-like than the thermosphere.
In fact, air in the exosphere is constantly - though
very gradually - "leaking" out of Earth's
atmosphere into outer space.
There is no clear-cut upper boundary where the
exosphere finally fades away into space.
Different definitions place the top of the exosphere
somewhere between 100,000 km (62,000 miles)
and 190,000 km (120,000 miles) above the surface
of Earth.
The latter value is about halfway to the Moon!
Exosphere
18. 18
The ionosphere is not a distinct layer like
the other mentioned above.
The ionosphere is a series of regions in
parts of the mesosphere and thermosphere
where high-energy radiation from the Sun
has knocked electrons loose from their
parent atoms and molecules.
The electrically charged atoms and
molecules that are formed in this way are
called ions, giving the ionosphere its name
and endowing this region with some
special properties.
Ionosphere
19. 19
Atmospheric Chemistry
The composition and chemistry of the Earth's atmosphere
is of importance for several reasons.
But, primarily because of the interactions between
o Atmosphere and
o Living organisms.
The composition of the Earth's atmosphere changes as
result of natural processes such as:
o Volcano emissions
o Lightning and
o Bombardment by solar particles from corona.
20. It has also been changed by human
activity and some of
these changes are harmful to:
o Human health
o Crops and
o Ecosystems.
Examples of problems which have
been addressed by
atmospheric chemistry include:
o Acid rain
o Ozone depletion
o Photochemical smog
o Greenhouse gases and
o Global warming.
20
21. 21
This phenomenon came to attention in the 1970s
Burning coal, oil and natural gas in power stations makes electricity,
giving off Sulphur dioxide gas.
Burning petrol and oil in vehicle engines gives off Nitrogen oxides as
gases.
Presence of H2SO4 (related to SO2 from coal combustion) and HNO3
(from NO2)
In the presence of lightning and thunderstorm, the nitrogen of the
atmosphere combines with oxygen to form nitric oxide (NO), which
in turn combines with oxygen to give nitrogen dioxide.
N2 + O2 ————→ 2 NO
2 NO + O2 ————→ 2 NO2
In the atmosphere, nitrogen dioxide reacts with water vapour
producing nitric acid, which is washed down as acid rain.
3 NO2 + H2O ————→ 2 HNO3 + NO
The formation of Nitric acid and Sulphuric acid as secondary
pollutants in the atmosphere leads to acid rain.
ACID RAIN
22. 22
All rain is acidic with or without air pollution.
This is due to the natural presence of carbon dioxide in the
atmosphere with dissolves in rain drops of rain water (even
moisture present in the atmosphere does the same function) to
form Carbonic acid.
CO2 + H2O → H2CO3
Due to the above reaction carbon dioxide can dissolve in water
until the solution becomes saturated.
This results in the rain water attaining an acidic pH of 5.6
Due to this, the purest form of rain reaches the earth as an
acidic solution of pH 5.6
Acidity causes Environmental problems like
o Destruction of vegetation
o Marine life
o Corrosion and
o Etching of buildings that are exposed to atmosphere.
ACID RAIN
23. 23
The trapping of heat by gases in the atmosphere.
Naturally occurring greenhouse gases:
Water vapor
Carbon dioxide
Methane
Nitrous oxide
Ozone
Greenhouse gases that are not naturally occurring
Hydro fluorocarbons (HFCs)
Per fluorocarbons (PFCs)
Sulfur hexafluoride (SF6)
Generated in a variety of
industrial processes.
Green house effect
24. 24
Some of the infrared
radiation passes
through the
atmosphere. some is
observed and reemitted
in all directions
by greenhouse gas
molecules. This causes
the earth surface and
lower atmosphere to
warm
Infrared radiation is
realized from the
Earth
Some Solar
radiation
redirected by
both the Earth
& atmosphere
The majority of the
radiation is absorbed
by the Earth’s
Surface with it
warms
Infrared radiation is
realized from the
Earth SurfaceEARTH
26. 26
Man-made causes of depletion of ozone layer:
• The main cause for the depletion of ozone is determined as
excessive release of chlorine and bromine from man-made
compounds such as chloro fluoro carbons (CFCs).
• CFCs (chlorofluorocarbons)
• Halogens
• CH3CCl3 (Methyl chloroform)
• CCl4(Carbon tetrachloride)
• HCFCs (hydro-chlorofluorocarbons)
• Hydro bromo fluoro carbons and
Methyl bromide are found to have direct impact on the depletion of the ozone layer.
• These are categorized as Ozone-Depleting Substances (ODS).
• Chlorofluorocarbons are released into the atmosphere due to:
o Cleaning Agents
o Coolants in refrigerators
o Packing material
o Air conditioning
o Aerosol spray cans etc.
Ozone depletion
27. 27
Why is the ozone layer important?
UV- Radiation DNA - damage
Skin Cancer