AIOU Solved Assignments 1 & 2 Code 1423 Autumn & Spring 2024

aiou solved assignment code 207

AIOU Solved Assignments 1 & 2 Code 1423 Autumn & Spring 2024. Solved Assignments environmental pollution 2024. Submit to allama iqbal open university tutors address.

AIOU Solved Assignments 1 & 2 Code 1423 Autumn & Spring 2024

SUBJECT: Environmental Pollution
CODE: 1423
SEMESTER: Autumn & Spring 2024
ASSIGNMENT No. 1

Q.No.1 Explain the torms environment, pollution and history of pollution. (20)

EPA’s Air, Climate, and Energy Research is at the forefront of air pollution research to protect public health and the environment.
The research is providing the scientific foundation for the U.S. Environmental Protection Agency, states and communities to make
decisions to effectively reduce and control air pollution.

Then

In October 1948, Donora Pa., was enveloped in a lethal haze.

Over five days, nearly half of the town’s 14,000 residents experienced severe respiratory or cardiovascular problems. It was
difficult to breathe. The death toll rose to nearly 40. Disturbing photos show Donora’s streets hidden under a thick~ a1lket of gray
smog. A warm air pocket had passed high above the town, trapping cooler air below and sealing in pollutants. Dollora was no
stranger to pollution. Steel and zinc smelters had long plagued the town with~ air. But the air pocket left  with no
escape route. They sat stewing in the streets, where residents breathed them ~ethal doses. The situation in Don~as extreme,
but it reflected a trend. Air pollution had become a harsh consequenof~ al growth across the c~~d orld. Crises
like Donora’s were widely publicized; people took notice and beg~~cientists started inves~ ~ge link between air
pollution and health. States began passing legislation to reduce air ~dnpfi. An~970, a milesto~ ~, Congress passed the
Clean Air Act Amendments which led to the establishment of the air aua~dards.

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Now

Today, policymakers and air quality managers rely og-‘edge science to es_ regulations and make management
decisions to reduce and control air pollution with ~e~ctive_ap~hes. EPA’s ~ Clirnate, and Energy Research conducts a
vast amount of this research, producing findinanddevel ~ chifology ~tdohr understanding of air pollution. For the
most common pollutants, the research is com~ d syn~~ery five~by EPA scientists to assess the adequacy of air
regulations.

EPA seeks to identify specific chemi~well as ~ esburce~ e ~ trucks and power plants) that can impact air quality.
A major goal is to pinpoint the s~ffibst respdtls~r heal ~

For example, EPA studies have ~own th~y~cles re hen gas, oil and other fossil fuels are burned harm the
respiratory and cardiovascular sems. ~ ritlwkno th se particles are especially harmful to the most vulnerable
populations: the young, older adults and thosth pre- ealth conditions. The research program provides an innovative
and interdisciplinary approach to the air pollution probl~ owned EPA scientists, engineers and physicians work together and
partner with scientific experts across the United Sta~~orldwide to address the many challenges of air quality management.

Future Directions

Major strides have been made to impro a~uality, but many complex scientific questions remain, calling for innovative and
novel research. It has become increa clear that multiple pollutants play a role in determining risks to people and the
environment. EPA is moving a “multipollutant” approach to air pollution research. It is crucial to understand the
collective impacts of multiple utants, how they interact in the atmosphere and whether the interactions modify health
effects. EPA’s Air, Climate ergy Research has already spearheaded interdisciplinary efforts to study combinations of
multiple pollutants more ly.

Research has linked regulated air pollutants such as ozone and particulate matter (PM) to lung and heart disease and other health
problems. More investigation is needed to further understand the role poor air quality plays on health and disease and support
development of more sustainable and integrated air quality management strategies. The findings are supporting the review of the
nation’s National Ambient Air Quality Standards (NAAQS).

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CRmate change and air quaRty interact

EPA is also pursuing an understanding of how climate change and air quality interact and the consequences for public health and
the environment. EPA scientists have already provided evidence that future temperature increases will increase air pollution levels
in some regions of the country. What’s more, urban areas already suffering from pollution problems may incur the greatest burden
of these changes. Advancements in air sensor monitoring technology is providing new lower-cost devices to help air quality
managers, communities and citizens with understanding air quality. EPA researchers are at the forefront of the development and evaluation of air sensor monitors. EPA will continue investigations of how climate change will impact the air we breathe, with a
focus on protecting current and future generations from air pollution health risks.

AIOU Solved Assignments Code 1423 Autumn & Spring 2024

QNo.2 Define and explain terrestrial and aquatic pollution in your own words. (20)

Creation of life form is because of environment. Sun/moon, sea/ earth, hot/ cold and forests/ desert etc; they together made an
environment that is fit for our existence. There are two different environments one is positive and the other one is negative, life
forms in both namely, pests, insects and others are cold blooded have different conditions which suits them to survive that may
not be suitable to us, both have own identities. Most important factor is that negative positive factors have to join together to form
an environment for example mother/ father for birth of a child, negative/ positive of energy for electricity. In the system of
environment, both have integral role to play. Where negative dominates outlines its systems and where positive dominates forms
its own.

Environment motivates to react:

We are miserable when are in desert and delighted when we are in lush garden. In a hospital we are in different mood and in disco
different. Environment motivates us to change om mood and reaction is in accordance.

We also generate/alter environment in our surroundings by our practice. Depends on the behavior of the individuals. Positive
thinkers have positive feelings and negative thinkers it is negative, creates environment accordingly. This poss turns to
evolutionary system when a group of people have same thinking that initiates others to follow. Human lust and exc~sage of
natural wood causing deforestation, pollution heating temperature is negative environment for us.

Maling decisions and taking action:

Environmental sustainability involves making decisions and taking~at arthe interests of ~~ g the natural world,
with particular emphasis on preserving the capability of the en~~t to suo uman life~ ~ important topic at the
present time, as people are realizing the full impact that bu~e~ and  s can havethe environment. What is
Environmental Sustainability?

Environmental sustainability is about making responsibledecisims that win reduceyour business’ negative impact on the
environment. It is not simply about reducing th~ot of wa~ou  oduce~lhang less energy, but is concerned with
developing processes that will lead to businesses becdmfflg completely sustainablemthe future.

Receives plenty of attention:

Currently, environmental sustainability is atopical issuethatreceivesplenty of attention from the media and from different
governmental departments. This is a ~ f the a~esearch ~ o assessing the impact that human activity can have
on the environment. Although  rm nnfr~~ of this~~e are not yet fully understood, it is generally agreed
that the risk is high enough to ~fan  respons~ sses are expected to lead in the area of environmental
sustainability as they are considered to be ~ ~~ st contri~d are also in a position where they can make a significant
difference.For much of the past, most busineave a ttle regard or concern for the negative impact they have on the
environment. Many large and small organizations are ~ of significantly polluting the environment and engaging in practices
that are simply not sustainable. However, there are nub ~mcreasing number of businesses that are committed to reducing their
damaging impact and even working towards havingapositive influence on environmental sustainability.

Sustainability forces businesses:

Environmental sustainability forces busmesse~to look beyond making short term gains and look at the long term impact they are
having on the natural world. You nee~hsider not only the immediate impact your actions have on the environment but the
long term implications as well. For ~-le, when manufacturing a product, you need to look at the environmental impact of the
products entire lifecycle, from d~ ~ent to disposal before finalizing your designs.

European environmental history today:

During the last 30 years environmental history grew from an interest of some historians and natural scientists into a full-fledged
academic discipline. In the United States environmental history gained a firm institutionalized base which is reflected in the fact
that the annual meetings of the American Society for Environmental History, established in 1975, attracts over 500 participants.
Environmental historical research in Europe is still fragmented but there are very promising and successful initiatives, both on the
national and pan-European level. In 1986, the Dutch foundation for the history of environment and hygiene Net Work was
founded. One of the most important goals of this foundation was to improve the communication between Dutch researchers with
an interest in environmental history. The foundation publishes four newsletters per year.

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Since 1995, the White Horse Press in Cambridge (IJK) is publishing a journal with the title Environment and History. As an
interdisciplinary journal, Environment and History aims to bring scholars in the humanities and biological sciences closer together
in constructing long and well-founded perspectives on present day environmental problems. The same can be said for the
Tijdschrift voor Ecologische Geschiedenis (Journal for Environmental History), a combined Flemish- Dutch initiative published

by the Academia Press in Gent, Belgium. This journal is mainly dealing with topics in the Netherlands and Belgium but it also has
an interest in European environmental history. Each issue contains abstracts in English, French and German. In 1999 the Journal
was changed into a yearbook for environmental eistory and since then every year a volume has been published. The aims and
content of this annual book is similar to the former journal.

The historian and environmental history:

Environmental history is an interdisciplinary subject. That means that historians, scientists and other scholars must look over the
boundaries of their own subject. The historian must be aware that he or she sometimes needs to apply some principles from the
natural sciences, such as ecology, biology and forestry, to understand what happened in the past. However, this does not mean that
the historian must become a scientist. He is and remains an historian with the task to master and understand the past as a key to a
better understanding of the present. But to do so he or she must look over the boundaries of history and even the humanities and
acquaint themselves with the nomenclature and principles of other disciplines, especially the natural sciences. This does not mean
that they have to become experts in these fields, but to use it as a tool to get a better understanding of historical problems.

Environmental historians:

Donald Worster has recognized three clusters of issues to be addressed by environmental historians. The first cluster deals with
the human intellectual realm consisting of perceptions, ethics, laws, myth and the other mental constructions related to the natural
world. Ideas about the world around us influence the way we deal with the natural environment. Here we enter the second level of
issues to be studied: the level of the socio-economic realm. Ideas have an impact on politics, policies and the ey through
which ideas materialize in the natural world.

Actions to influence the material world:

But the world is not static, so it reacts on our actions to influence the ~~ orld. With the impact ~~ actions the natural
world we enter the third level of environmental history. This level ~ un~dmg nature~ ~ e natural realm. In the
case of woodland history it is the way forest ecosystems have  kingtm|ufber~st and ho~th~ were changed by human
actions. The impact of human actions on the natural world is ~ a fee~b~hanges s, policies, economy etc. In
this way the natural world defines the limits of what we~o~d what~ Withm th~ ork we try to change reactions
we do not like and continue practices which, in o  succe~. This mode teraction between man and the
environment depicts the concept of the separation ~~anslilpd n~e. Althou division between the human and the
natural realms is an artificial one, it can be a use~ for ~ eh~nmental hi in identifying important questions, the
sources that might be able to answer the questions and[tf[1e methodsused to studythesesources.

Moreover: AIOU Solved Assignments code 1429

AIOU Solved Assignments Code 1423 Autumn & spring 2024

Q.No.3 Discuss the sources of air pollution with speeialreference toindoor air poRution.(20)
Man-made Environment

With the development of science~chn~ y~an bein_gs~egun to alter the environment to suit their requirements.
This has led to the evolution of a Ifian-mad~e ~ment. H~ ffie environment which earlier comprised just air, land and
water-now also includes crop fields, urban ~ indu , vehicles, power plants, telecommunications, and much more.

The basic needs of human beings are shelter, followe~~table water and sanitation. The houses of people in the city are made
of brick and cement and not of mud with a thatch~he resources for urban housing are transported from rural areas in cars,
buses, trucks and trains, which consume a ~~t of energy and pollute the atmosphere. The ever-increasing demand for
comfort has resulted in the migration of pe  villages to urban areas. Urban areas, on the other hand are unable to meet the
demands of basic civic amenities. As a r~ t,~ey are becoming hovels of dirt, disease and crime. This has resulted in the paradox
of concrete skyscrapers coexisting wit~ and the atmosphere being polluted with exhaust from traffic, factories and domestic
smoke.

Hydrosphere:

AH types of water resource~amely the oceans, seas, rivers, lakes, ponds, polar ice caps, streams, glaciers, ground water, and
water vapour are collectively known as the hydrosphere. Water being the ehxir of life, all ancient civilizations were linked to
major sources of water, be it the Egyptian Civilization along the River Nile, the Indus VaHey Civilization along the River Indus,
or the Mesopotamian Civilization between the Tigris and Euphrates rivers.

The hydrosphere is an important part of the earth’s surface. About 70 per cent of the earth’s surface is covered with water. The
northern hemisphere is dominated by land surface, while the southern hemisphere is almost entirely occupied by water bodies
(oceans). Water is the most essential component of life for all living organisms. The hydrosphere is of immense importance to
mankind. It maintains the availability of fresh water to the biosphere through the hydrological cycle. A major component of the
hydrological cycle is the ocean. The oceans are great reservoirs of water and they also regulate carbon dioxide. The oceans can
absorb more carbon dioxide than the atmosphere. Oceans are also the storehouses of vast resources, such as, water, salt, minerals,
and food. The oceans are the largest sinks (pollutant receptor) of the planet. Thus, the role of the hydrosphere is critical to the
sustenance of life on the earth. This is underlined by the fact that life on the earth originated under marine conditions.

Lithosphere:

The lithosphere is the outermost mantle of the rocks constituting the earth’s crust. Rocks are subjected to continuous physical,
chemical and biological (attack by lichens) weathering. Plants grow and decay on the soil covering the rocks. Soil is the major
component of the lithosphere. The organic matter in soil is decomposed by micro-organisms, thus forming biomass. This biomass
is mixed with the soil fauna. The major components of soil are air, water, minerals, and inorganic matter obtained from
weathering of the parent rock. Organic matter of soil comprises plant biomass that is in various stages of decay. It also includes a
high population of bacteria fungi and animals such as nematodes, micro arthropods, termites and earthworms. Soil plays a vital
role in supplying nutrients to the plant kingdom. The nutrient supply power of soil is a measure of its fertility, while the
productivity of the soil is a function of crop and animal biomass per unit area. Thus, the yield of crop depends solely on soil and
crop management strategies.

The lithosphere has a thickness ranging from 64 to 96 km. The uppermost part of the lithosphere (the earths crust) is rich in silica
(Si) and aluminium (Al) and is therefore, known as the SiAl layer. The continents belong to the SiAl layer and are made up of
granite rocks.

The zone next to the SiAl is rich in silica (Si) and magnesium (Mg). This layer is formed of basalt rocks and constitutes the ocean
floors. The basalt rocks are heavier than the rocks formed by SiAl layer. Below the SiMg layer, the density of the layers increases
with depth. Such differences in density cause the constituting layers to float, one over the other. The continents are basically large
segments or _plates’ of the earth’s crust floating on top of this heavier layer. These floating plates are responsible~~e tectonic
movement of the earth’s surface during an earthquake.

Lithosphere and thickness

Below the lithosphere hes the mande, which has a thickness of abuf|h2500km. The upper part ofmantle is known as the
Asthenosphere, while the lower mantle is called the Mesosphere.~hr|erior-~art of the ~called the Core, which
consists of minerals such as iron, nickel, cobalt mixed with sulphui~ sili~~ckness of~e~ re extends to about 3500
km. The Core consists of the outer core and the inner core. core a~t soli~whe outer core is molten and
metallic. The temperature of the core ranges between 5000 and5/!iOOoC.  _

The direct interaction between the atmosphere, hy~ ~and li~ sp ~ for milli~~years has made the earth suitable for
life and has formed the biosphere.

Biosphere: Life on earth occupies a _thin~ ten~an a fe~ etres below and above its surface. This is
commonly known as the biosphere. Bo~~osph~ ~vironm~fluence each other a lot. The oxygen and carbon
dioxide levels of the atmosphere depend~ly ~l~t~ kmgd ~ the different biogeochemical cycles are essential for
ou cula6on of constituents necessaryforsupportmg life.Thisis possible due to the interaction of the biosphere and

It is in the biosphere that radiant energy is converted tochemical form (carbohydrates) through the process of photosynthesis.
Only then does energy transfer take place fromemical t~hanical, and heat forms during cellular metabolism.

AIOU Solved Assignments Code 1423

Q.No.4 Explain the structure of atmospllere.Support your answer with suitable diagram. (20)

The changes in the atmosphere with hei~results of specific physical conditions which exist on the earth and in its
atmosphere. The vertical changes in tcmf|er;hure are important in constraining weather events to the lowest 10-12 km of the
atmosphere. The ozone layer, located 5 km above the eartlr s surface, causes the temperature to rapidly change in the middle
atmosphere.

Acid rain describes any form of precipitation with high levels of nitric and sulfuric acids. It can also occur in the form of snow,
fog, and tiny bits of dry material that settle to Earth. Rotting vegetation and erupting volcanoes release some chemicals that can
cause acid rain, but most acid rain falls because of human activities. The biggest culprit is the burning of fossil fuels by coal-
burning power plants, factories, and automobiles. When humans burn fossil fuels, sulfur dioxide (SO2) and nitrogen oxides (NOx)
are released into the atmosphere. These chemical gases react with water, oxygen, and other substances to form mild solutions of
sulfuric and nitric acid. Winds may spread these acidic solutions across the atmosphere and over hundreds of miles. When acid
rain reaches Earth, it flows across the surface in runoff water, enters water systems, and sinks into the soil.

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Effects

Acid rain has many ecological effects, but none is greater than its impact on lakes, streams, wetlands, and other aquatic
environments. Acid rain makes waters acidic, and causes them to absorb the aluminum that makes its way from soil into lakes and
streams. This combination makes waters toxic to crayfish, clams, fish, and other aquatic animals.

 Earth as a Green-house

Gases that trap heat in the atmosphere are called greenhouse gases. This section provides information on emissi~ movals
of the main greenhouse gases to and from the atmosphere. For more info~on on the science of climate ~afig and other
climate forcers, such as black carbon, please visit Climate Change Science.

Carbon dioxide (CO2): Carbon dioxide enters the atmosphere thring fossil fuels (coal,~ gas, and oil), solid
waste, trees and wood products, and also as a result of certain ch   ons ~ manufacture ~ceinerlt). Carbon dioxide is
removed from the atmosphere (or “sequestered”) when it is absorbed byplantsthe biological carbon cycle.

Methane (CH4): Methane is emitted during the produ~ons~ sp ~c~ na~d oil. Methane emissions also
result from livestock and other agricultural practices and bythedecay oforgank: waste inumnieipal solid waste landfills.

Nitrous oxide (N2O): Nitrous oxide is emitted d~~cul~ ~dustrial a~ as well as during combustion of fossil
fuels and solid waste.

Fluorinated gases: Hydro fluorocarbon ~roc~n~ hexa~ and nitrogen trifluoride are synthetic, powerful
greenhouse gases that are emitted frorlln~ of~~1=process~ofinated gases are sometimes used as substitutes for
stratospheric ozone-depleting subs~.g., ch~ ~ ar~ ~ chlorofluorocarbons, and halons). These gases are
typically emitted in smaller qu~ut be~~ are po ouse gases, they are sometimes referred to as High
Global Warming Potential gases (“High GWPgases”).

Coping with Global Warming

The world is on track to reach dangerous levIs~~lbbal warming much sooner than expected, according to new Australian
research that highlights the alarming implicationsofrising energy demand.

University of Queensland and Griffith  iv~ity researchers have developed a “global energy tracker” which predicts average
world temperatures could climb 1.5C ~e pre-industrial levels by 2024. That forecast, based on new modelling using long-term
average projections on economic gr~~ulation growth and energy use per person, points to a 2C rise by 2030.

The UN conference on clima ~~ge in Paris last year agreed to a I.5C rise as the preferred limit to protect vulnerable island
states, and a 2C rise as the~te limit. The more the economy grows, the more energy you use … the conclusion really is that
economists and environmen ts are on the same side and have both come to the same conclusion: we’ve got to act now and we
don’t have much time.”

Wagner said the model suggested the surge in energy consumption was not offset by improvements in energy efficiency. He said
energy use per person was on track to rise six fold by 2050, which had dire implications for temperatures when combined with
economic growth of 3.9% a year (the six-decade average) and a world population of 9 billion. “Massive increases in energy
consumption would be necessary to alleviate poverty for the nearly 50% of the world’s population who live on less than $2.50 a
day. “We have a choice: leave people in poverty and speed towards dangerous global warming through the increased use of fossil
fuels, or transition rapidly to renewable.”

More than one million readers have now supported our independent, investigative journalism through contributions, membership
or subscriptions, which has played such an important part in helping The Guardian overcome a perHous financial situation
globally. We want to thank you for all of your support. But we have to maintain and build on that support for every year to come.

Sustained support from our readers enables us to continue pursuing difficult stories in challenging times of political upheaval,
when factual reporting has never been more critical. The Guardian is editorially independent – our journalism is free from
commercial bias and not influenced by billionaire owners, politicians or shareholders. No one edits our editor. No one steers our
opinion. This is important because it enables us to give a voice to those less heard, chaHenge the powerful and hold them to
account. Readers’ support means we can continue bringing The Guardian’s independent journalism to the world.

The gaseous area surrounding the planet is divided into several concemri~trata or layers. About 99%. of the total atmospheric
mass is concentrated in the first 20 miles (32 km) above Earth’s s~ ~ ~orical outline on the ~ of atmospheric
structure.

TffE~ STRUCTURE

Atmospheric layers are characterized by variations in ~ e resul~ ptifharHy ~ absorption of solar radiation;
avisibletmosphlit at the surface, near ultraviolet radiationmiddleatmosphere, and]hr ultraviolet radiation in the upper

Troposphere

The troposphere is the atmospheric layer closest To the contain_ sthe largest percentage (around 80%) of the mass of the
total atmosphere. Temperature and ~vapbr e tropos~~dease rapidly with altitude. Water vapor plays a
major role in regulating air te hecause solar ~ d thermal radiation from the planet’s surface. The
troposphere contains 99 % of the~vapor sphere. ~vapbr concentrations vary with latitude. They are greatest
above the tropics, where they may be as highas3 %,and decreasetoward the polar regions.

AH weather phenomena occur within the tropo~ere, al~turbulence may extend into the lower portion of the stratosphere.
Troposphere means “region of mixing” and is so named because of vigorous convective air currents within the layer.

The upper boundary of the layer, known as the e, ranges in height from 5 miles (8 km) near the poles up to I I miles (18
km) above the equator. Its height also variethe seasons; highest in the summer and lowest in the winter.

Stratosphere

The stratosphere is the second m~~ta of air in the atmosphere. It extends above the tropopause to an altitude of about 30
miles (50 km) above the plan~ e. The air temperature in the stratosphere remains relatively constant up to an altitude of 15
miles (25 km). Then it incr~duaHy to up to the stratopause. Because the air temperature in the stratosphere increases with
altitude, it does not cause ~ on and has a stabilizing effect on atmospheric conditions in the region. Ozone plays the major
role in regulating the thermal regime of the stratosphere, as water vapor content within the layer is very low. Temperature
increases with ozone concentration. Solar energy is converted to kinetic energy when ozone molecules absorb ultraviolet
radiation, resulting in heating of the stratosphere.

The ozone layer is centered at an altitude between 10-15 miles (15-25 km). Approximately 90 % of the ozone in the atmosphere
resides in the stratosphere. Ozone concentration in the this region is about 10 parts per million by volume (ppmv) as compared to
approximately 0.04 ppmv in the troposphere. Ozone absorbs the bulk of solar ultraviolet radiation in wavelengths from 290 nm –
320 nm (UV-B radiation). These wavelengths are harmful to life because they can be absorbed by the nucleic acid in cells.
Inaeased penetration of ultraviolet radiation to the planet’s surface would damage plant life and have harmful environmental
consequences. Appreciably large amounts of solar ultraviolet radiation would result in a host of biological effects, such as a
dramatic increase in cancers.

Mesosphere

The mesosphere a layer extending tiom approximately 30 to 50 miles (50 to 85 km) above the surface, is characterized by
decreasing temperatures. The coldest temperatures in Earth’s atmosphere occur at the top of this layer, the mesopause, especially
in the summer near the pole. The mesosphere has sometimes jocularly been referred to as the “ignorosphere” because it had been
probably the least studied of the atmospheric layers. The stratosphere and mesosphere together are sometimes referred to as the
middle atmosphere.

Thermosphere

The thermosphere is located above the mesosphere. The temperature in the thermosphere generaHy increases with altitude
reaching 600 to 3000 F (600-2000 K) depending on solar activity. This increase in temperature is due to the absorption of intense
solar radiation by the limited amount of remaining molecular oxygen. At this extreme altitude gas molecules are widely separated.
Above 60 miles (100 km) from Earth’s surface the chemical composition of air becomes strongly dependent on altitude and the
atmosphere becomes enriched with lighter gases (atomic oxygen, helium and hydrogen). Also at 60 miles (100 km) altitude,
Earth’s atmosphere becomes too thin to support aircraft and vehicles need to travel at orbital velocities to stay aloft. This
demarcation between aeronautics and astronautics is known as the Karman Line. Above about 100 miles (160 km) altitude the
major atmospheric component becomes atomic oxygen. At very high altitudes, the residual gases begin to stratify according to
molecular mass, because of gravitational separation.

Exosphere

The exosphere is the most distant atmospheric region from Earth’s surface. exosphere, an upward travel~ olecule can
escape to space (if it is moving fast enough) or be pulled back to Earth b (if it isn’t) with little ab`~ of colliding
with another molecule. The altitude of its lower boundary, known as th ause or exobase, range bout 150 to 300
miles (250-500 km) depending on solar activity. The upper boun efined theoreticaHy by de (about 120,000
miles, half the distance to the Moon) at which the influence of sol pre~on atomic h velocities exceeds that
of the Earth’s gravitational pull. The exosphere observable fromf8p the~~ is seen t to at least 60,000 miles
from the surface of the Earth. The exosphere is a transitional zonebetween  osphereand interplanetary space.

MAGNETO-ELECTROMC STfiUCTURE

The upper atmosphere is also divided into regions basedon the behavior and numberof &ee electrons and other charged particles.

D-region is about 35 to 55 miles (60 90 Inn) in altitude but disappears at night.
E-region is about 55 to 90 miles (90 140 km) in altitude.
F-region is above 90 miles (140 km) in atitude. During the day it has two regions Imown as the Fl-region from about 90 to 115
miles (140 to 180 km) altitude and the F2-region in which the concentration of electrons peaks in the altitude range of 150 to 300
miles (around 250 to 500 km). Most recent map of the Height of Maximum (hmF2). The ionosphere above the peak electron
concentration is usually referred to as the Topside ionosphere.

Plasma sphere

The plasmasphere is not reaHy spherical but a doughnut-shapedregion(a torus) with the ]hole aligned with Earth’s magnetic axis.
[In this case the use of the suffix -sphere is more ~e~tive sen~ a “sphere  ce”.] The Earth’s plasmasphere is
made of just that, a plasma, the fourth state of mat~~ your ~on s6rtlng fas of matter with the Matter Sorter.) This
plasma is composed mostly of hydrogen ions oto~and e~~s. has a v edge called theplasmapause. The outer
edge of this doughnut over the equator is us~ome 4~~ radii ~ the center of the Earth or 12,000-20,000 miles
(19,000-32,000 km) above the surface. Th~ ph i~ffally an ~~idn of the ionosphere. Inside of the plasmapause,
geomagnetic field lines rotate with the E~e inn~ e pla~ e is taI;:en as the altitude at which protons replace
oxygen as the dorninant species in ~~osph which ~curs at about 600 miles (1000 km) altitude. The
plasmasphere can also be consideredtobe a strtletureWithin the magnetosphere.Magnetosphere

Outside the plasmapause, magnetic field lines are unable to coronate because they are influenced strongly by electric fields of
solar wind origin. The magnetosphere is a cavity (also not spherical) in which the Earth’s magnetic field is constrained by the solar
wind and interplanetary magnetic field (IMF). The outer boundary of the magnetosphere is called the magnetopause. The
magnetosphere is shaped like an elongated teardrop (like a Christmas Tree ornament) with the tail pointing away from the Sun.
The magnetopause is typically located at about 10 Earth radii or some 35,000 miles (about 56,000 km) above the Earth’s surface
on the day side and stretches into a long tail, the magneto tail, a few million miles long (about 1000 Earth radii), well past the orbit

of the Moon (at around 60 Earth radii), on the night side of the Earth. However, the Moon itself is usually not within the
magnetosphere except for a couple of days around the Full Moon.

Beyond the magnetopause are the magneto sheath and bow shock which are regions in the solar wind disturbed by the presence of
Earth and its magnetic field. are regions in the solar wind disturbed by the presence of Earth and its magnetic field.

Solved AIOU Assignments Code 1423 Autumn & Spring 2024

Q.No.5 Write short notes on the foRowings:

a. Enlist major air poRutants

Major air pollutions are:

Carbon Monoxide (CO)

Pollutants facts Fuel combustion from vehicles and engines. Pollutants factsReduces the amount of oxygen reaching the body’s
organs and tissues; aggravates heart disease, resulting in chest pain and other symptoms.

Ground-level Ozone (03)

Pollutants fact sSecondary pollutant formed by chemical reaction of volatileorganic compounds (VOCs) andNOx i11Rle presence
of sunlight. Pollutants factsDecreases lung function and causes respira~ptoms, such as coughin~s1fortness of breath,
and also makes asthma and other lung diseases get worse. More on 6mum;f Level C)zone Here

Lead (Pb)

Pollutants factsSmelters (metal refineries) and oth dustrie~mb~tion of~ gasoline in piston engine aircraft;
waste incinerators (waste burners), and battery man g.

P.Ilutants fact sDamages the developing nervous system,resulting in IQ lossand impacts on learning, memory, and behavior in
children. Cardiovascular and renal e~ adults effectare anaemia.

Nitrogen Dioxide (NO2)

Pollutants factsFuel combustion (electric utilities, big industrial boilers, vehicles) and wood burning.

Pollutants factsWorsens lung diseases leading to r symptoms, increased susceptibility to respiratory infection.

Particulate Matter (PM)

Pollutants factsThis is formed throu~~ical reactions, fuel combustion (e.g., burning coal, wood, diesel), industrial processes,
farming (plowing, field burninpaved roads or during road constructions. Pollutants factsShort-term exposures can

worsen heart or lung diseas~use respiratory problems. Long..term exposures can cause heart or lung disease and sometimes
premature deaths.

Sulfur Dioxide (SO2)

Pollutants facts SO2 comes from fuel combustion (especially high-sulfur coal); electric utilities and industrial processes as well as
natural occurrences like volcanoes. Pollutants factsAggravates asthma and makes breathing difficult. It also contributes to particle
formation with associated health effects.

b. Effects of acid deposition

Acid rain describes any form of precipitation with high levels of nitric and sulfuric acids. It can also occur in the form of snow,
fog, and tiny bits of dry material that settle to Earth. Rotting vegetation and erupting volcanoes release some chemicals that can
cause acid rain, but most acid rain falls because of human activities. The biggest culprit is the burning of fossil fuels by coal-
burning power plants, factories, and automobiles. When humans burn fossil fuels, sulfur dioxide (SO2) and nitrogen oxides (NOx)
are released into the atmosphere. These chemical gases react with water, oxygen, and other substances to form mild solutions of
sulfuric and nitric acid. Winds may spread these acidic solutions across the atmosphere and over hundreds of miles. When acid
rain reaches Earth, it flows across the surface in runoff water, enters water systems, and sinks into the soil.

Effects

Acid rain has many ecological effects, but none is greater than its impact on lakes, streams, wetlands, and other aquatic
environments. Acid rain makes waters acidic, and causes them to absorb the aluminum that makes its way from soil into lakes and
streams. This combination makes waters toxic to crayfish, clams, fish, and other aquatic animals.

 Earth as a Green-house

Gases that trap heat in the atmosphere are called greenhouse gases. This section provides information on emissi~ movals
of the main greenhouse gases to and from the atmosphere. For more info~on on the science of climate ~afig and other
climate forcers, such as black carbon, please visit Climate Change Science.

Carbon dioxide (CO2): Carbon dioxide enters the atmosphere thring fossil fuels (coal,~ gas, and oil), solid
waste, trees and wood products, and also as a result of certain ch   ons ~ manufacture ~ceinerlt). Carbon dioxide is
removed from the atmosphere (or “sequestered”) when it is absorbed byplantsthe biological carbon cycle.

Methane (CH4): Methane is emitted during the produ~ons~ sp ~c~ na~d oil. Methane emissions also
result from livestock and other agricultural practices and bythedecay oforgank: waste inumnieipal solid waste landfills.

Nitrous oxide (N2O): Nitrous oxide is emitted d~~cul~ ~dustrial a~ as well as during combustion of fossil
fuels and solid waste.

Fluorinated gases: Hydro fluorocarbon ~roc~n~ hexa~ and nitrogen trifluoride are synthetic, powerful
greenhouse gases that are emitted frorlln~ of~~1=process~ofinated gases are sometimes used as substitutes for
stratospheric ozone-depleting subs~.g., ch~ ~ ar~ ~ chlorofluorocarbons, and halons). These gases are
typically emitted in smaller qu~ut be~~ are po ouse gases, they are sometimes referred to as High
Global Warming Potential gases (“High GWPgases”).

Coping with Global Warming

The world is on track to reach dangerous levIs~~lbbal warming much sooner than expected, according to new Australian
research that highlights the alarming implicationsofrising energy demand.

University of Queensland and Griffith  iv~ity researchers have developed a “global energy tracker” which predicts average
world temperatures could climb 1.5C ~e pre-industrial levels by 2024. That forecast, based on new modelling using long-term
average projections on economic gr~~ulation growth and energy use per person, points to a 2C rise by 2030.

The UN conference on clima ~~ge in Paris last year agreed to a I.5C rise as the preferred limit to protect vulnerable island
states, and a 2C rise as the~te limit. The more the economy grows, the more energy you use … the conclusion really is that
economists and environmen ts are on the same side and have both come to the same conclusion: we’ve got to act now and we
don’t have much time.”

Wagner said the model suggested the surge in energy consumption was not offset by improvements in energy efficiency. He said
energy use per person was on track to rise six fold by 2050, which had dire implications for temperatures when combined with
economic growth of 3.9% a year (the six-decade average) and a world population of 9 billion. “Massive increases in energy
consumption would be necessary to alleviate poverty for the nearly 50% of the world’s population who live on less than $2.50 a
day. “We have a choice: leave people in poverty and speed towards dangerous global warming through the increased use of fossil
fuels, or transition rapidly to renewable.”

More than one million readers have now supported our independent, investigative journalism through contributions, membership
or subscriptions, which has played such an important part in helping The Guardian overcome a perHous financial situation
globally. We want to thank you for all of your support. But we have to maintain and build on that support for every year to come.

Sustained support from our readers enables us to continue pursuing difficult stories in challenging times of political upheaval,
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