Ozone layer
About 20 Kilometers thick, this giant umbrella is made up of a layer of ozone gas. This gas
is found some 15 to 35 kilometers above the Earth's surface in the upper atmosphere or
"stratosphere".
Although ozone (O3) is present in small concentrations throughout the atmosphere, most
ozone (about 90%) exists in the stratosphere, in a layer between 10 and 50km above the
surface of the earth. This ozone layer performs the essential task of filtering out most of the
sun's biologically harmful ultraviolet (UV-B) radiation. Concentrations of ozone in the
atmosphere vary naturally according to temperature, weather, latitude and altitude.
Furthermore, aerosols and other particles ejected by natural events such as volcanic
eruptions can have measurable impacts on ozone levels.
If the ozone layer was brought down to the Earth's surface, air pressure and temperature
conditions would compress the ozone into a layer 2 to 5 mm thick!
What Is Stratospheric Ozone?
Ozone is a natural gas that is found in two different layers of the atmosphere. In the layer
around the Earth's surface (the troposphere) ground-level, or bad ozone dirties the air and
helps make smog. The troposphere extends up to the stratosphere layer, where good ozone
protects life on Earth by absorbing some of the sun's UV rays. Stratospheric ozone is found
most often between six to 30 miles above the Earth's surface.
Ozone Depletion
Recently, chlorofluorocarbons (CFCs) were used a lot in industry and elsewhere to keep
things cold, make foam, and soaps. Strong winds carry CFCs into the stratosphere. This can
take two to five years. When CFCs break down in the stratosphere, they release chlorine.
Each chlorine atom attacks ozone by joining with and breaking apart as many as 100,000
ozone molecules during the time it is in the stratosphere.
Other ozone eating chemicals are pesticides such as methyl bromide, halons used in fire
extinguishers, and methyl chloroform used in businesses. If all ozone-depleting chemicals
were successfully phased out, the ozone layer would eventually heal itself.
OZONE HOLE
Antarctic during the In 1985, scientists identified a thinning of the ozone layer over the
scientific evidence shows that spring months which became known as the "ozone hole". The
creation of the Antarctic ozone hole and are human-made chemicals are responsible for the
global ozone losses also likely to play a role in
What you can do to protect the Ozone Layer
Try to find out as much as you can about the problem from publications, schools or public
libraries. The only way to mend the ozone hole is to stop the release of CFCs and other
ozone depleting substances (ODS) into the atmosphere. European legislation aims to
achieve this by phasing out ODS as soon as viable alternatives become available, and where
no such alternatives are available, restricting the use of these substances as far as possible.
However, there are a number of practical initiatives which can be taken at the individual
level to help protect the ozone layer:
First International Conference on MSECCMI, New Delhi, India, 2007
EVALUATION OF LAND DEGRADATION DUE TO COAL MINING- A VIBRANT ISSUE
Ruchi Singh*, Prasoon Kr. Singh** and Gurdeep Singh***
* - Research Scholar, ESE, ISMU, Dhanbad
** - Asstt. Prof., ESE,ISMU, Dhanbad
***- Prof. & Head, ESE, ISMU, Dhanbad, Jharkhand, INDIA
Abstract
Mining operations degrade significant areas of land and replace existing ecosystem with
undesirable waste materials in form of mine spoil dumps. The
coal extraction process drastically alters the
physical and biological nature of the mined area, so land protection is a very important aspect
and has to be given utmost significance right from the initial state of mining operation.
Unfortunately in most of the mining areas in India, exploitation of mineral resources had been
carried out in early days with least regards to land protection and even without any plan for
future land use. This is particularly true for the coal mining industries in India. Such unscientific
mining has caused huge degradation of land, massive subsidence of strata, disturbance of water
table causing severe ecological imbalance. The top soil is completely damaged if it is not
separately mined in beginning with a view to reclamation. This is particularly necessary due to
scarcity of top soil in the coalfield areas. Thus, the overall impact is very much alarming and it
has become a vital issue for thinking in advance. The reclamation of degraded land has become
a great challenge to Indian mining industry. The present paper focuses in brief about the
different aspects of impact on land environment particularly with a case discussion of coal
mining area.
Introduction
Land is a non-renewable asset and it is the main component of damage by mining. Mining operations
degrade significant areas of land and replace existing ecosystems with undesirable waste materials in
form of mine spoil dumps. The coal extraction process drastically alters the physical and biological
nature of the mined area. Open cast mining particularly, destroys vegetation, causes extensive soil
damage and destruction and alters microbial communities. Coal mining is a developmental activity
which is bound to damage land use pattern in the area, and hence damages the land. The matter is very
serious in India because of the following facts:
1 India holds about 16 % of global population in about 2.3 % of global land area.
2. Forest protects land and environment best, and is an important component of ecosystem. Thus,
3. India's National Forest Policy states that the requirement of 33 % forest cover, but the country is far
behind the target.
Realizing the above fact a “grow more greenery " move was started in early 1980s but even after that
forest cover in the country is not increasing.
Thus, landforms are such an important component of environment that if its quality is protected
properly, it can help in protecting the quality of all other aspects of environment. But, mining activities
damages this very important, scarce and limited natural resource very effectively. It is very much
required that these damages are repaired and the lands are reclaimed. This should be done at the
earliest because effects of damage to land are cumulative. The matter is very serious in Indian condition
because coal mining started in nineteenth century when the need of environmental protection was
beyond realization; and even now proper technology to repair the damages has not been developed in
certain aspects.
The Indian Scenario of Mining Environment
Although the country has thousands of years of history of mining the real concern towards the
environmental management in the mining areas is only about three decades old.
Mining is second only to agriculture as the world's oldest and most important industry. There
has been spectacular growth in production of coal and lignite. There is a growing awareness of
pollution problems from mines, especially the problems of waste disposal in surface mines, air
and water pollution in mining belts and destruction of vegetation and forests. Public concern
and opposition is growing to mining projects. In India, being a developing country,
environmental mishaps are common while striking a balance in developing activities and
environmental requirements. This is a stupendous task, more so in case of India where land
area is only 2.3 % of the globe and population is as high as 16 % of the world's total (current
population of India is more than 100 crores).
Therefore, there is a great challenge to implement the various legal measures, blending with
environmental awareness campaigns without jeopardizing the interests of developing activities.
So, with the increasing use of coal as the main energy source, the environmental concerns
associated with coal mining and its utilization is coming into sharp focus.
Causes Of Land Degradation
The causes of land degradations are given as below:
Loss of vegetation:
As discussed above mining starts from the loss of the vegetation in the areas specific, dumping
and other associated activities. And this loss of vegetation results in drastic changes in climatic
condition like rainfall, temperature, and humidity
Siltation
There are many instances of siltation of low lying land around the dumps in the mining
complexes, which has affected the fertility and usefulness of the land.
Pits/Excavation :
Opencast mining causes extensive damages to the land. In the hill areas excavations done for
miining not only damage the area excavated but also the uphill land causing landslides and
vegetation loss and in many cases driving out fauna from their actual habitats.
Waste dumps:
The waste / overburden dumps block the land on which these are made for the time period of
their existence. In addition to degradation of land on which the dumps are made they also
degrade the surrounding land due to leachate, also changes in the local drainage pattern and
ground water condition.
Soil quality:
The standard practices of opencast mining involve separate removal, handling and storage of
top-soil and sub-soils so that these can be re-laid during reclamation of the mined out areas.
Invariably in the opencast mines in India the soils are not selectively handled as a result the soil
material get mixed with overburden rock mass and thus the soil, an important resource of the
land management , is lost.
Mining also disturbs soils sequences as well as due to loosening of the ground the natural
compactness of the soils reduces as a result the soils become prone to erosion due to the rain
and wind.
Damage to agricultural land and creation of wasteland
The Indian Bureau of Mines opines that surface mining may result in constant decline of green
and cultivable areas which is by way of blockage of land for mining and allied activities. An
estimated by IBM, this degradation is to the tune of 60% by waste dumping, 23% by pit
excavation and 17% by others.
Extent of Damage by Mining Methods:
Mining activities both by underground as well as by open cast methods affect the land in
various ways:
a
Impacts of opencast mining :
1. Topography changes due to digging of open pits and dumping of overburden rock/ stone
masses.
2. The land-use pattern undergoes a change due to the use of the land for mining, dumping
and other mining and associated activities.
.3 Leachets from overburden dumps and other rock masses affect the characteristics of the
top soil.
4. Preparation of tailing dams need land and may cause pollution of nearby underground and
surface water sources.
5. The drainage pattern on the surface undergoes a change due to the alterations in the
surface topography for mining and associated activities.
b
Impacts of underground mining :
1. Changes in land-use due to constructions and infrastructure development.
2. Changes in topography and drainage pattern due to subsidence.
3. Discharge of polluted water from the underground mines affects the top-soil on the surface.
Land Degradation Cycle:
Coal mining requires both - i.e., deforestation and excavation. Whatever the amount of land
disturbed by mining and related activities the fact is, once the erosion starts, it joins the cycle,
i.e., " cycle of land degradation "
turn As the mining starts the single process of vacating the land is bound to damage green
cover on land and disintegration of soil particles by excavation. The above process initiates the
“cycle of land degradation “by generating more of barren land. This allows direct effect of
sunlight and rain on land. This results high erosion, the eroded particles fall on surface
depressions (siltation). This causes results more barren period of land (by not drying up of
surface water bodies, hence decrease in irrigation potential of the region. This in allowing any
irrigated crop to grow) and drying up of land. This aggravates erosion potential of the land i.e.,
the three processes drying up of land, increased erosion and damage to greenery work
simultaMining activities both by underground as well as by open cast methods affect the land in
various
The Indian Bureau of Mines opines that surface mining may result in constant decline of green
and cultivable areas which is by way of blockage of land for
mining and allied activities. An estimated by IBM, this degradation is to the tune of 60% by
waste dumping, 23% by pit excavation and 17% by others.
ways:
a
Impacts of opencast mining :
1. Topography changes due to digging of open pits and dumping of overburden rock/ stone
masses.
2. The land-use pattern undergoes a change due to the use of the land for mining, dumping
and other mining and associated activities.
.3 Leachets from overburden dumps and other rock masses affect the characteristics of the
top soil.
4. Preparation of tailing dams need land and may cause pollution of nearby underground and
surface water sources.
5. The drainage pattern on the surface undergoes a change due to the alterations in the
surface topography for mining and associated activities.
b
Impacts of underground mining :
1. Changes in land-use due to constructions and infrastructure development.
2. Changes in topography and drainage pattern due to subsidence.
3. Discharge of polluted water from the underground mines affects the top-soil on the surface.
Coal mining requires both - i.e., deforestation and excavation. Whatever the amount of land
disturbed by mining and related activities the fact is, once the erosion starts, it joins the cycle,
i.e., " cycle of land degradation "
As the mining starts the single process of vacating the land is bound to damage green cover on
land and disintegration of soil particles by excavation. The above process initiates the “cycle of
land degradation “by generating more of barren land. This allows direct effect of sunlight and
rain on land. This results high erosion, the eroded particles fall on surface depressions
(siltation). This causes drying up of surface water bodies, hence decrease in irrigation potential
of the region. This in turn results more barren period of land (by not allowing any irrigated crop
to grow) and drying up of land. This aggravates erosion potential of the land i.e., the three
neously one helping the other, thus accelerating and aggravating the process. Finally the land
gets degraded.
Blasting is required for loosening the hard rocks but the fly rocks generated by this spread over
the surrounding land and disturb its uses and usability.
Overburden dumps if unreclaimed renders the dumping ground useless for ever. The dumps get
leached by rain water, the leachates with varied composition may spread over the land and
pollute it.
Top Soil Assessment:
To human, the most important part of the geosphere is soil. Though only a tissue-thin layer
compared to earth's total diameter, soil is the medium for the production of most food, upon
which most living things depend. Good soil and a climate conducive to its productivity is the
most valuable asset a nation can have. Apart from supporting plant growth it provides a habitat
for a large number of animals and microorganisms. In addition to being the site of the most
food production, soil is the receptor of large quantities of pollutants.
Topsoil is an essential component for land reclamation in coal mining areas. The topsoil is very
seriously damaged if it is not mined out separately in the beginning, with a view to replacement
for due reclamation of the area. This is particularly necessary due to the scarcity of top soil in
the coalfields.
Status of Land Degradation in Jharia Coalfield
Region :
As mining is one of the major activities in the Jharia coalfield region, land degradation caused
due to mining is appreciable. Due to opencast mining and underground operations, a great
extent of land is being continuously degraded by openpits, overburdens dumps, mine fire,
subsidence etc. Quality of land is becoming similar to that of waste land resulting in spoiling of
highly fertile agricultural lands.
Jharia coalfield is one of the most important coalfields in India. This is the most exploited
coalfield because of metallurgical grade coal reserves available in this area. Prior to
nationalization, mining in this coalfield was in the hands of private enterpreneurs, who had
limited resources and lack of desire for scientific mining. Both
131
opencasts and underground mining methods were adopted. The opencast mining areas were
not backfilled, and as a result large voids were created in the abandoned mining areas.
Extraction of thick seams by caving at shallow depths damaged the ground surface in the form
of subsidence and formation of cracks reaching surface thus enhancing chances of spontaneous
heating of coal seams.
One of the major environmental impacts of surface mining operation is that it causes damage
to the land, forest, agriculture and disturbance of the drainage system and hydrology of the
area. By creating ugly dumps at any site, the soil stability and productivity are adversely
affected and erosion takes place. The land area affected in the Jharia coalfield region has been
shown in Table - 1.
Table - 1: Status of Affected Area of Land in Jharia Coalfield Region
Sl. No.
Causes
Affected Area
(in sq.km.)
1.
By fire
17.32
2.
By subsidence
39.47
3.
By excavation
12.68
4.
By dumps
6.30
To tal Area
(in sq.km.)
71.27
Different types of land units (mining areas to agricultural lands) characterize land use pattern of
Damodar basin in which the Jharia coalfield centrally situated. It significantly differs in upper,
middle and lower valley regions as a function of geomorphology, geology and topography. In
the upper valley, the forest area (wood lands) dominates and croplands find their location along
the river valleys and rugged topography. With this topographical set up, this area is under
dense vegetation cover of mixed forest type. The dissected edge of the plateau at the west of
Gomia divides the major land use pattern of this region into (i) even crusted low hillls with
forest cover, (ii) croplands in forest blanks at the west, and (iii) undulating rolling uplands with
bare vegetation but spotted with mining scars on the east. Gully erosion affects the cropping
pattern in uplands and plateau edges, especially around Tilaiya in the north of Hazaribagh
region. In the middle valley, Gondwana trough is spotted with coal mines and allied industrial
centres for which forest areas have been removed for industrial and settlement growth.
Dhanbad - Asansol area is marked by high industrial activity. In Jharia coalfield region, nonagricultural use of land dominates and cropland s have decreased in considerable extent. Large
stretches of orchards and croplands around the raniganj coalfield are intermingled with nonagricultural land. From Durgapur, towards west and south, wide patches of woodlands
comprising mainly of sal forest occupy an appreciable area. The lower valley region has an
identical land use pattern of agricultural lands consisting of rice fields and orchards of various
shapes and dimensions. Croplands gradually increase in extent from Durgapur to down southeastern tip of the basin and stretches about 30km wide from either side of the Damodar river.
This type of land has changed while approaching the Hooghly river, where urban features
replace typical agricultural scenario.
At least 40 % (17.5 lakh hectares ) of land in the upper catchment of the Damodar river, in parts
of Hazaribagh, Ranchi, Palamau, Dhanbad, Giridih and Santhal Parganas districts of Jharkhand
and in parts of Purulia district of West Bengal, suffers from soil erosion of varying degrees. The
land of upper basin requires extensive reclamation treatment and wastelands have to be
transformed to vegetative cover by massive afforestation.
Mitigation Measures:
To mitigate the impacts of mining on land, two basic strategies are required to follow; these are
“land reclamation " and " land use planning ". It is a true fact that any mining degraded land
should be “reclaimed “at the earliest possible opportunity, while reclamation means putting the
land to a beneficial use.
Planning for rehabilitation, reclamation and closure of mines involves the following :
1. Assessment of prevailing, i.e. pre-mining land use of the area and the surroundings.
2. Assessment of the pre-mining surface drainage pattern.
3. Study of structure of the mineral deposit/body and the geology of the area concerned.
4. Design of the method of working keeping in view the prevailing land use so as to have
minimum possible impacts of mining on the land use.
5. Assessment of the life of the mine and the quality of the overburden to be kept out side the
mine including the period for which the overburden will be kept out side.
132
Another important thing is the soil management. If the mineral to mine is deep seated, covered
by OB and top soil, preservation of this top soil is very important. It is to be collected separately
by scraping the top 10-15 cm layer (depending upon the soil profile) and stored properly to
preserve its bio life and physical properties. In Indian condition (tropical climate) these are
vulnerable to erosion and if lost will create serious ecological damage by forming siltation on
surrounding land and water and also creating loss of top soil, worthy natural resource ; as
nature takes several years to form 1 cm of top soil.
Conclusion:
Mining is a dirty, dusty operation by its very nature. But, there is no doubt that mining is a vital
sector of the economy in any country. The bowels of the earth conceal vast riches of minerals
and ores, which man has learnt to extract and fashion into countless goods of daily use and
several uses on which the wheels of industry depend.
Degree of land degradation depends upon the type of mining. Open surface mining being the
largest user of land usually presents greater problems than other methods of mining. During
the opening of an open pit or quarrying, the valuable overburden of top soil and subsoil get
destroyed, groundwater flows are interrupted and the land use is totally altered. And changes
in land use are bound to produce over a period of time changes in the human ecological
system.
Therefore reclamation with suitable materials is the correct process of reforming and regrading
the waste land approximately to the original topography and bringing about permanent self
sustaining vegetation.
FLOODS
INTRODUCTION
After prayers to the rain gods, answered in excess in parts of our country, now,
the focus has shifted to floods. Many states in our country are flood prone due to
heavy rain or otherwise. The flood causes loss to human life and wide spread
damage to property. Unimaginable damage to agriculture takes place affecting
the States planning and upset the financial budgeting there by slowing down the
whole economy of the country.
People not affected by the flood tend to ignore the event thinking that it does not
affect them so why bother?.
Flood is not unique to our country. Floods come in different parts of the world.
Floods are the biggest cause of loss of life every year through out globe. Majority
of countries do not document or map floods methodically. People are generally
taken by surprise by the floods as they may come in the night when every body is
asleep, giving very little time for evacuation. Water remains stag anent after the
flood recedes, source of drinking water get polluted and the food get spoiled.
People are left with no resource to combat the natural calamity that has take
place. Floods are ugly part of our system we cannot ignore or wish them away.
The only way to fight the floods is to try to predict the flood, prepare for it, train
and educate people. identify areas, which are flood prone.
What is flood
The term "flood" is a general or temporary condition of partial or complete
inundation of normally dry land areas from overflow of inland or tidal waters or
from the unusual and rapid accumulation or runoff of surface waters from any
source.
Flooding and flash flooding are the deadliest of natural disasters. Floodwaters
claim thousands of lives every year and render millions homeless. One of the
more frightening things about flooding is that it can occur nearly anywhere, at any
time. It can result from excess water jams on rivers, even moderate rain, or a
single very heavy downpour as it occurred in Himachal Pradesh recently.
"In the last 30 years, inland flooding has been responsible for more than half the
deaths associated with tropical cyclones in the United States."
Ed Rappaport
National Hurricane Center
What causes Flood ?
Heavy down pore in the form of rain, brings down more water than can be
disposed off by combined factors natural and man made systems causes flooding.
The rivers overflow embankments may be breached. Generally rains following
storm and hurricane are heavy and bring unmanageable amount of water causing
flash floods.
The frequency or probability of a flood usually is described by assigning a
recurrence interval to the flood at each gaging station. This is accomplished by
statistically evaluating long-term annual peak stream flows at a station. Standard
techniques and procedures used to determine the station flood-frequency relations
are described by the U.S. Water Resources Council (1982). For example, a 100year flood-recurrence interval means that, in any given year, a flood of a specified
stream flow magnitude has a 1-in-100 chance of happening.
Rainfall is generally heaviest with slower moving storms (less than 10 mph).
To estimate the total rainfall in inches from a hurricane, divide 100 by the forward
speed of the storm in miles per hour (100 / forward speed = estimated inches of
rain).
When it comes to hurricanes, wind speeds do not tell the whole story. Hurricanes
produce storm surges, tornadoes, and often the most deadly of all - inland
flooding.
While storm surge is always a potential threat, more people have died from inland
flooding in the last 30 years. Intense rainfall is not directly related to the wind
speed of tropical cyclones. In fact, some of the greatest rainfall amounts occur
from weaker storms that drift slowly or stall over an area.
Inland flooding can be a major threat to communities hundreds of miles from the
coast as intense rain falls from these huge tropical air masses.
The ingredients for a hurricane include a pre-existing weather disturbance, warm
tropical oceans, moisture, and relatively light winds aloft. If the right conditions
persist long enough, they can combine to produce the violent winds, incredible
waves, torrential rains, and floods we associate with this phenomenon.
Each year, an average of ten tropical storms develop over the Atlantic Ocean,
Caribbean Sea, and Gulf of Mexico. Many of these remain over the ocean and
become hurricanes each year. In an average 3-year period, roughly five hurricanes
strike the US coastline, killing approximately 50 to 100 people anywhere from
Texas to Maine. Of these, two are typically "major" or "intense" hurricanes (a
never impact the U.S. coastline. Six of these storms
category 3 or higher storm on the Saffir -Simpson Hurricane Scale.
A hurricane is a type of tropical cyclone, which is a generic term for a low pressure
system that generally forms in the tropics. The cyclone is accompanied by
thunderstorms and, in the Northern Hemisphere, a counterclockwise circulation of
winds near the earth's surface. Tropical cyclones are classified as follows:
Sustained winds
A 1-minute average wind measured at about 33 ft (10 meters) above the surface.
1 knot = 1 nautical mile per hour or 1.15 statute miles per hour. Abbreviated as
"kt".
Man made causes for floods
Man causes most of the pollution in this world.
man made cause would be global warming, deforestation, urbanization all cause flooding.
Recent Floods in India
ARUNACHAL PRADESH (As on 9-07- 2003):
8 districts viz. W/ Kamang, P/ para, E/ Siang, W/ Siang, U/ Siang, Lohit, Changlanf and Tirap
have been affected in varying degrees due to floods/heavy rains and landslides since 15.6.2003.
Detailed reports from districts are awaited. State Government has instructed districts authorities
to take necessary rescue & relief measures in the affected areas. Flood affected people evacuated
to safe places. Roads communication disrupted. Petrol pump, play ground, water tanks &
pipelines were also reported damaged due to floods and landslides.
Damage due to Cyclone, Heavy Rains & Flood during - South- West Monsoon, 2003
(Provisional, As on 10-07-2003)
Affected
Damage
lives lost
S.N States/U Cala Total Distri Talukas/ Villa Tot Popula Cro Estim Hou Estimat Estimated Hum Cattl
o.
T's
mity Distri cts Blocks/ ges al tion
ps ated ses
ed
value of an
es
cts (No.) Mpls.
Ar
(in
are value (No. value
Public (No.) (No.
(No.)
ea lakh)
a
of
)
of
properties
)
(in
(in crops
houses
(Rs. in
lak
lak (Rs. in
(Rs. in Crores)
h
h crores
crores)
Ha.
Ha.
)
)
)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
1 Arunac HR/F
hal
/L
Pradesh
15
8
12
10
NR
NR
NR
NR
NR
NR
2.29
NR
NR
2 Assam
HR/F
23
20
NR
2614 2.6 18.18 0.6
3
8
NR
2667
NR
NR
6
NR
3 Bihar
HR/F
38
5
13
262 2.0
0
2.39
0.0
7
0.02
38
0.91
NR
8
Nil
4 Kerala
HR/F
/L
14
14
NR
404 NR
0.06
0.2
8
0.33 1440
0.84
0.01
24
Nil
5 Orissa
HR/F
1
3
39
0.0
4
NR
NR
NR
NR
NR
NR
NR
NR
6 Madhya HR/F
Pradesh
45
2
NR
NR NR
NR
NR
NR
NR
NR
NR
10
NR
7 Mahara HR/F
shtra
35
16
25
176 NR
NR
NR
NR
513
NR
0.48
35
119
8 Meghal HR/F
aya
1
NR
NR NR
NR
NR
NR
NR
NR
NR
1
NR
9 West
Bengal
6
NR
NR NR
NR
NR
NR
NR
NR
NR
17
NR
TOTA
L :-
HR/L
73
3505
20.63 1.0
3
0.35 4658
101
Note: F - Flood, FF- Flash Flood, L - Landslide, HR - Heavy Rains, C - Cyclone, NR - Not
Reported, Neg.- Negligible
What Is the Greenhouse Effect?
What is Greenhouse effect: The effect produced as greenhouse gases allow incoming solar radiation to
pass through the Earth's atmosphere, but prevent most of the outgoing infrared radiation from the
surface and lower atmosphere from escaping into outer space. This process occurs naturally and has
kept the Earth's temperature about 60 degrees Fahrenheit warmer than it would otherwise be. Current
life on Earth could not be sustained without the natural greenhouse effect.
The greenhouse effect is the rise in temperature that the Earth experiences because certain gases in the
atmosphere (water vapor, carbon dioxide, nitrous oxide, and methane, for example) trap energy from
the sun. Without these gases, heat would escape back into space and Earth’s average temperature
would be about 60ºF colder. Because of how they warm our world, these gases are referred to as
greenhouse gases.
The Earth’s atmosphere is all around us. It is the air that we breathe. Greenhouse gases in the
atmosphere behave much like the glass panes in a greenhouse. Sunlight enters the Earth's atmosphere,
passing through the blanket of greenhouse gases. As it reaches the Earth's surface, land, water, and
biosphere absorb the sunlight’s energy. Once absorbed, this energy is sent back into the atmosphere.
Some of the energy passes back into space, but much of it remains trapped in the atmosphere by the
greenhouse gases, causing our world to heat up.
Greenhouse Effect is need of atmosphere ?
The greenhouse effect is important. Without the greenhouse effect, the Earth would not be warm
enough for humans to live. But if the greenhouse effect becomes stronger, it could make the Earth
warmer than usual. Even a little extra warming may cause problems for humans, plants, and animals.
Greenhouse Gases :
Any gas that absorbs infra-red radiation in the atmosphere. Greenhouse gases include water vapor,
carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), halogenated fluorocarbons (HCFCs) , ozone
(O3), perfluorinated carbons (PFCs), and hydrofluorocarbons (HFCs).
Dangers
An average global temperature rise is 0.2°C to 0.3°C every decade. Meaning over the next
hundred years there could be large consequences, because some areas in the world will get much
higher average increase than others. The temperature on earth's surface is heated by the process
called the greenhouse effect. Growth in industry and transportation have used and burned more
products, such as fossil fuels or trees, resulting in them making more greenhouse gases and
putting them into the atmosphere. This results in more heat in the colder places. So all the ice
melts in the colder places and then the places that are hot the sea level rises and that result in
more floods.
The Kyoto Protocol is the treaty that was signed by many countries to help prevent more
greenhouse gases. The less greenhouse gases there are in the atmosphere the less dangerous the
greenhouse effect is. The countries signed this treaty to reduce the amount of greenhouse gases
that are put in the atmosphere because if there are to many they will cause global warming. The
treaty was open for signature on March 16, 1998. The United States signed this on November 12,
1998. Their target was to reduce their amount of greenhouse gases put in the atmosphere by 7%.
In all the Kyoto Protocol was a great idea and if it works out like it is supposed to we can prevent
all the consequences of having too much greenhouse gases in our atmosphere.
Environmental Pollution and Its
Effects
One of the greatest problems that the world is
facing today is that of environmental pollution,
increasing with every passing year and causing
grave and irreparable damage to the earth.
Environmental pollution consists of five basic types
of pollution, namely, air, water, soil, noise and
light.
Air pollution is by far the most harmful form of pollution in our
environment. Air pollution is cause by the injurious smoke emitted by
cars, buses, trucks, trains, and factories, namely sulphur dioxide, carbon
monoxide and nitrogen oxides. Even smoke from burning leaves and
cigarettes are harmful to the environment causing a lot of damage to man
and the atmosphere. Evidence of increasing air pollution is seen in lung
cancer, asthma, allergies, and various breathing problems along with
severe and irreparable damage to flora and fauna. Even the most natural
phenomenon of migratory birds has been hampered, with severe air
pollution preventing them from reaching their seasonal metropolitan
destinations of centuries.
Chlorofluorocarbons (CFC), released from refrigerators, airconditioners, deodorants and insect repellents cause severe damage to
the Earth’s environment. This gas has slowly damaged the atmosphere
and depleted the ozone layer leading to global warming.
Water pollution caused industrial waste products released into lakes,
rivers, and other water bodies, has made marine life no longer
hospitable. Humans pollute water with large scale disposal of garbage,
flowers, ashes and other household waste. In many rural areas one can
still find people bathing and cooking in the same water, making it
incredibly filthy. Acid rain further adds to water pollution in the water.
In addition to these, thermal pollution and the depletion of dissolved
oxygen aggravate the already worsened condition of the water bodies.
Water pollution can also indirectly occur as an offshoot of soil pollution
– through surface runoff and leaching to groundwater.
Noise pollution, soil pollution and light pollution too are the damaging
the environment at an alarming rate. Noise pollution include aircraft
noise, noise of cars, buses, and trucks, vehicle horns, loudspeakers, and
industry noise, as well as high-intensity sonar effects which are
extremely harmful for the environment.
Maximum noise pollution occurs due to one of modern
science’s best discoveries – the motor vehicle, which
is responsible for about ninety percent of all unwanted
noise worldwide.
Soil pollution, which can also be called soil contamination, is a result of
acid rain, polluted water, fertilizers etc., which leads to bad crops. Soil
contamination occurs when chemicals are released by spill or
underground storage tank leakage which releases heavy contaminants
into the soil. These may
include hydrocarbons, heavy metals, MTBE, herbicides, pesticides and
chlorinated hydrocarbons.
Light Pollution includes light trespass, over-illumination and
astronomical interference.
Radioactive pollution and its effects on
human beings
What is Radioactive Pollution?
Radioactive pollution can be defined as the emission of high energy particles or radioactive
substance into air, water or land due to human activities in the form of radioactive waste.
Radioactive waste is usually the product of a nuclear process such as nuclear fission, which is
extensively used in nuclear reactors, nuclear weapons and other nuclear fuel-cycles.
The radioactivity of nuclear waste diminishes with time. That means the waste needs to be
isolated from the reach of living beings until it no longer pose a threat to living beings. This time
period may take from days to months and to years depending upon the radioactive nature of the
waste.
Radioactive pollution that is spread through the earth’s atmosphere is called “Fallout”. The
atmospheric nuclear pollution become prominent during the world war 2 period when United
States, Britain and Soviet Union started conducting nuclear tests in the atmosphere. The best
example of fallout is the nuclear bomb attack on Hiroshima and Nagasaki, Japan in 1945 by
United States of America during world war 2.
As a result of nuclear bomb attack, nearly 2,25,000 people had died as a result of long-term
exposure to radiation from the bomb blast within 5 years of attack due to radiation effect and
cancer.
In land and water, the major source of radioactive pollution remains with the nuclear fuel cycle.
The nuclear fuel cycle is used in nuclear power plants, extraction and refinement of materials
from nuclear substance to be used in nuclear reactors and nuclear weapons, where the
contaminants are left behind after the useful material (Nuclear Isotope) is extracted.
Effects of Radioactive Pollution on human beings:
The effects of radioactive pollution or exposure to nuclear radiations were first reported in early
20th century when people working in uranium mines suffered from skin burn and cancer. The
effects vary from organism to organism and from level of radioactivity of nuclear isotopes. The
radiations destroy the cells in human body and causes cancer.
Radioactive particles forms ions when it reacts with biological molecules. These ions then form
free radicals which slowly and steadily start destroying proteins, membranes, and nucleic acids.
A longer exposure to radioactive radiations can damage the DNA cells that results in cancer,
genetic defects for the generations to come and even death.
Sources of radioactive contaminants:
Following are the major sources where most of the radioactive waste is generated and is
responsible for causing radioactive pollution:
o
Production of nuclear fuel
o
Nuclear power reactors
o
Use of Radionuclides in industries for various applications
o
Nuclear tests carried out by Defense Personnel
o
Disposal of nuclear waste
o
Uranium Mining
Frequency and Duration of Radioactive Pollution:
Atmospheric pollution is not a constant or regular phenomenon and therefore the frequency and
duration of pollution will vary with time and conditions. The three major types of conditions
exists
Continuous pollution: This type of condition exists in uranium mines, nuclear reactors, test labs
etc. where the humans are under continuous exposure to radioactive contaminants and protective
clothing is required to avoid radiation exposure.
Accidental Pollution: This type of condition exists during accidental exposure to radiations by
virtue of equipment failure, radiation leak, faulty protective equipment etc.
Occasional Pollution: This condition exists during isolated experiment or test of nuclear
substance.
r.a.p. in water
nuclear r a p
RAP
Drought images