What are Green House Effect and Global Warming? Discuss the problem due to Global Climate Change.

Earth is constantly bombarded with enormous amounts of radiation, primarily from the sun. This solar

radiation strikes the Earth's atmosphere in the form of visible light, plus ultraviolet (UV), infrared (IR)

and other types of radiation that are invisible to the human eye.

UV radiation has a shorter wavelength and a higher energy level than visible light, while IR radiation has

a longer wavelength and a weaker energy level. About 30 percent of the radiation striking Earth's

atmosphere is immediately reflected back out to space by clouds, ice, snow, sand and other reflective

surfaces, according to NASA. The remaining 70 percent of incoming solar radiation is absorbed by the

oceans, the land and the atmosphere.

Green house effect

It's this equilibrium of incoming and outgoing radiation that makes the Earth habitable

The exchange of incoming and outgoing radiation that warms the Earth is often referred to as the

greenhouse effect because a greenhouse works in much the same way.

Incoming UV radiation easily passes through the glass walls of a greenhouse and is absorbed by the

plants and hard surfaces inside. Weaker IR radiation, however, has difficulty passing through the glass

walls and is trapped inside, thus warming the greenhouse. This effect lets tropical plants thrive inside a

greenhouse, even during a cold winter

Carbon dioxide (CO2) and other greenhouse gases act like a blanket, absorbing IR radiation and

preventing it from escaping into outer space. The net effect is the gradual heating of Earth's atmosphere

and surface, a process known as global warming.

People

Water use

-1) Decline in drinking water

Decline in irrigation supplies. Loss of mountain snowpack reduces the amount of water available for irrigation downstream

Effects on recreation. Reduced snowpack and earlier spring snowmelt put traditional winter sports, such as skiing and snowmobiling, at risk, while lower water levels in lakes and rivers increase the costs of maintaining recreational amenities

Higher shipping costs. Lower lake and river levels may reduce the capacity of ships to carry freight safely

Food

Reduced yields. The productivity of crops and livestock, including milk yields

ncreased irrigation. Regions of the world that now depend on rain-fed agriculture

Planting and harvesting changes. Shifting seasonal rainfall patterns

More pests. Insect and plant pests may survive or even reproduce more often each year if cold winters no longer keep them in check

Health

Extreme heat.

Natural" disasters.

Climate trends differ by region:- People who live in floodplains, for example, are more likely to see river or coastal flooding.

Freshwater:-

Extreme wet

Wet places tend to get wetter. Atmospheric circulation over oceans, plains, and mountains helps determine where rainforests thrive and semi-arid regions develop. However, wet places tend to get wetter and dry places dryer in a warming world—as is already occurring today. Places now wetter than the historical average include Northern Europe, eastern North and South America, and

northern and central Asia

Extreme dry

Increased drought in dry areas

Land ice

Sea-level rise. Water from shrinking glaciers and ice sheets is now the major contributor to global sea-level rise.

Long-term decline in water resources. Nearly one-sixth of the world's population lives near rivers that derive their water from glaciers and snow cover.

Short-term increase in flash floods

Oceans

Sea level

Sea ice

Accelerated warming from albedo. Lost sea ice exposes dark, open waters, dramatically shifting the ocean surface from highly reflective to one that absorbs most of the sun's energy.

Threats to indigenous ways of life. These changes in animal habitat and abundance threaten indigenous ways of life, some of which have flourished in the Arctic

Security concerns from new shipping routes.

Ocean chemistry

Acidification occur

Ecosystem

Displacement of cold-water species

Effects on reproduction

Stress.

Disease. The more intense precipitation that accompanies a warming world makes river flooding more likely

Land

Increase in agricultural pests. Agricultural pests formerly constrained to low-latitude locales are moving to higher latitudes as those regions warm

Forced migrations and extinctions.

Changing woodlands

Salt water

Forced migrations

coral bleaching

Temperature

The ozone depletion process begins when CFCs and other ozone-depleting substances (ODS) are

emitted into the atmosphere(1). Winds efficiently mix the troposphere and evenly distribute the gases.

CFCs are extremely stable, and they do not dissolve in rain. After a period of several years, ODS

molecules reach the stratosphere, about 10 kilometers above the Earth's surface (2).

Strong UV light breaks apart the ODS molecule. CFCs, HCFCs, carbon tetrachloride, methyl

chloroform, and other gases release chlorine atoms, and halons and methyl bromide release bromine

atoms (3). It is these atoms that actually destroy ozone

one chlorine atom can destroy over 100,000 ozone molecules before it is removed from the stratosphere (4).

1. What id Ozone layer depletion? Discuss its causes and impacts.

Effects of the Ozone Hole

Thinning of ozone layer means getting direct in touch with ultra violet rays which can cause skin cancer or

skin irritation which can lead to death. A decrease in 1% of ozone layer can cause 5% increase in cases

of skin cancer.

Exposure to UV rays has also increased the cases of cataracts which in turn affects people’s vision and

could also cause an increase in people becoming blind.

Depletion of ozone layer and increase in UV rays can also cause DNA damage which can also be

catastrophic.

Aquatic plants and animals are not even safe. UV rays can penetrate through water and can kill small

plants and animals. If ozone hole keep on expanding, there would be very few plants which means less

food in the whole world.

The effect of the ozone hole and the damage done to the layer is still not very well understood. Apart from

the gradual decrease of the ozone layer all over the world, there is little quantifiable evidence of new

holes appearing any time soon. Even so, a number of countries have been working towards mitigating the

damage.

CFC’s have been banned, especially in aerosol cans and various electrical appliances. There have been

many conventions held to discuss the methods that will slowly phase out the use of the gases. However,

this has been met with a great deal of resistance from industries that are based on the production and

use of the gases.

However, the few known and verifiable effects seen within the environment has been a catalyst for

change. One of widespread and long lasting effects has been the public awareness towards the

environmental issues facing the planet. As one of the first major man-made problems to be discussed on

a public forum, it set the ground for public opinion and action on issues such as pollution, green house

gases, global warming and the climate crisis.

It also sparked off renewed research about how weather patterns and natural phenomenon may be

disturbed small changes in the atmosphere. Ozone depletion is not as serious as it once was, but

nonetheless it has had an impact on the planet.

Scientists have been able to determine a number of consequences related to ozone depletion. First is the

increase of UVB (Ultraviolet B) light that enters into the atmosphere. This causes environmental damage

and problems in human health. Cancer of the skin is being connected to the thinning of the ozone layer.

In the animal kingdom, many species of animals have been found suffering from growing sunburn as a

result of increased UV light. Certain crops will also be affected, since they are dependent on

cyanobacteria which is quite sensitive to changing levels of the UV radiation. On the other hand, it has

also been found that the increased levels allow for the production of more Vitamin D in the animal

kingdom.

The ozone layer does not face rampant ozone depletion anymore, as most governments and

environmental agencies have worked hard to reduce the emission of CFCs. This has proven to be a

success and is the base for further work in reducing dangerous emissions.

Causes of Ozone Hole

The destruction of ozone layer is caused by one factor only which is Cholorofluorocarbons.

The main cause of the ozone hole was found to be gases that contained Cholorofluorocarbons (CFCs),

Halons and Freons. Found commonly in aerosol cans and released by many electronic appliances, these

were seen to decrease the level of ozone in the stratosphere. All of these gases contain chlorine, which is

a major cause behind the thinning of the ozone layer.

The presence of chlorine within CFC’s break down the ozone gases in ozone layer which increases the

chances of ozone depletion. Till date, CFC’s have accounted for about 80% of ozone depletion.

The destruction of the ozone layer is primarily caused when the amount of gases that contain chlorine

begins to increase in the environment. As these gases rise upwards, they are exposed to UV light. This

then causes a chemical reaction which creates chlorine atoms. These affect the atoms of ozone

and cause ozone depletion.

Although the process has been taking place for several years, the ozone layer was repairing itself

naturally. With the marked increase in the emission of these gases, the ozone hole above Antarctica is

becoming a permanent part of the layer. Even though the damage is reversible, it will require several

decades and a major reduction in the emissions.

CFC’s are not washed back to the earth and are not even destroyed in reaction with other chemicals

which means that they can remain the atmosphere for large period of time may be from 20 to 120 years

or more. As a result, they are transported back to stratosphere, where they are eventually broken down

by UV rays from the sun, releasing free chlorine.

2. Discuss Wasteland and its reclamation.

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Reclamation of waste land means re-claiming it or to use it for productive purposes.

1. Afforestation:It means growing the forest over culturable wasteland.

2. Reforestation:

Growing the forest again over the lands where they were existing and was destroyed due to fires,

overgrazing, and excessive cutting. Reforestation checks water logging, floods, soil erosion and increase

productivity of land.

3. Providing surface cover:

The easiest way to protect the land surface from soil erosion is of leave crop residue on the land after

harvesting.

4. Mulching:

Here also protective cover of organic matter and plants like stalks, cotton stalks, tobacco stalks etc. are

used which reduce evaporation, help in retaining soil moisture and reduce soil erosion.

5. Changing Ground Topography on Downhill’s:

Running water erodes the hill soil and carries the soil along with it. This can be minimized by following

alternation in ground topography:

(a) Strip farming:

Different kinds of crops are planted in alternate strip along the contour.

(b) Terracing:

In this arrangement, the earth is shaped in the form of levelled terraces to hold soil and water. The terrace

edges are planted with such plant species which anchor the soil.

(c) Contour ploughing:

In this arrangement, the ploughing of land is done across the hill and not in up and down style.

6. Leaching:

In salt affected land, the salinity can be minimized by leaching them with more water.

7. Changing agricultural practices:

Like mixed cropping, crop rotation and cropping of plants are adopted to improve soil fertility.

8. Ecological Succession:

This refers to the natural development or redevelopment of an ecosystem which help in reclaiming the

minerally deficient soil of wasteland.

3. How can we create Public Environmental Awareness?

Targeted Efforts According to UNEP, environmental awareness campaigns are most successful when targeted to specific groups or

populations. Many people don't pay much attention to environmental problems because they don't understand how

the problem would affect them or their lifestyle. One reason that hybrid cars, energy-saving appliances, and solar

panels have become so popular in the past few years is because of targeted awareness.

Local Outreach Environmental education is just as important in the developing world as it is in industrialized nations; however,

reaching out to the people in those countries can be very difficult. Language barriers, illiteracy, and cultural

differences can prevent them from learning about environmental issues, particularly in rural or tribal areas. Reaching

out to tribal, religious, and community leaders can often help a government organization or non-governmental

organization (NGO) educate the people on environmental issues.

The Media In developed countries and urban areas, the use of print, broadcast, and Internet media can be a great way to increase

education and awareness. By working with the media, government agencies and nonprofit organizations can help

spread their message, either by holding press briefings, issuing printed press releases, or even setting up online

databases that can be used as information centers. Information centers can be useful tools to educate both the public

and journalists about environmental concerns.

4 Discuss the various age pyramids associate with population.

There are generally three types of population pyramids created from age-sex distributions--expansive, constrictive and stationary.

EXPANSIVE population pyramids show larger numbers or percentages of the population in the

younger age groups. These types of pyramids are usually found in populations with very large fertility

rates and lower than average life expectancies. The age-sex distributions of many Third World

countries would probably display expansive population pyramids.

CONSTRICTIVE population pyramids display lower numbers or percentages of younger people. The

age-sex distributions of the United States fall into this type of pyramid.

STATIONARY or near-stationary population pyramids display somewhat equal numbers or

percentages for almost all age groups. Of course, smaller figures are still to be expected at the oldest

age groups. The age-sex distributions of some European countries, especially Scandinavian ones,

will tend to fall into this category.

Main Causes of Soil Pollution

1. Industrial Activity: Industrial activity has been the biggest contributor to the problem in the last

century, especially since the amount of mining and manufacturing has increased. Most industries are

dependent on extracting minerals from the Earth. Whether it is iron ore or coal, the by products are

contaminated and they are not disposed off in a manner that can be considered safe. As a result,

theindustrial waste lingers in the soil surface for a long time and makes it unsuitable for use.

2. Agricultural Activities: Chemical utilization has gone up tremendously since technology provided us

with modern pesticides and fertilizers. They are full of chemicals that are not produced in nature and

cannot be broken down by it. As a result, they seep into the ground after they mix with water and slowly

reduce the fertility of the soil. Other chemicals damage the composition of the soil and make it easier to

erode by water and air. Plants absorb many of these pesticides and when they decompose, they cause

soil pollution since they become a part of the land.

3. Waste Disposal: Finally, a growing cause for concern is how we dispose of our waste. While industrial

waste is sure to cause contamination, there is another way in which we are adding to the pollution. Every

human produces a certain amount of personal waste products by way or urine and feces.

While much of it moves into the sewer the system, there is also a large amount that is dumped directly

into landfills in the form of diapers. Even the sewer system ends at the landfill, where the biological

wastepollutes the soil and water. This is because our bodies are full of toxins and chemicals which are

now seeping into the land and causing pollution of soil.

4. Accidental Oil Spills: Oil leaks can happen during storage and transport of chemicals. This can be

seen at most of the fuel stations. The chemicals present in the fuel deteriorates the quality of soil and

make them unsuitable for cultivation. These chemicals can enter into the groundwater through soil and

make the water undrinkable.

5. Acid Rain: Acid rain is caused when pollutants present in the air mixes up with the rain and fall back

on the ground. The polluted water could dissolve away some of the important nutrients found in soil and

change the structure of the soil.

Effects of Soil Pollution

1. Effect on Health of Humans: Considering how soil is the reason we are able to sustain ourselves, the

contamination of it has major consequences on our health. Crops and plants grown on polluted soil

absorb much of the pollution and then pass these on to us. This could explain the sudden surge in small

and terminal illnesses.

Long term exposure to such soil can affect the genetic make-up of the body, causing congenital illnesses

and chronic health problems that cannot be cured easily. In fact, it can sicken the livestock to a

considerable extent and cause food poisoning over a long period of time. The soil pollution can even lead

to widespread famines if the plants are unable to grow in it.

2. Effect on Growth of Plants: The ecological balance of any system gets affected due to the

widespread contamination of the soil. Most plants are unable to adapt when the chemistry of the soil

changes so radically in a short period of time. Fungi and bacteria found in the soil that bind it together

begin to decline, which creates an additional problem of soil erosion.

The fertility slowly diminishes, making land unsuitable for agriculture and any local vegetation to survive.

The soil pollution causes large tracts of land to become hazardous to health. Unlike deserts, which are

suitable for its native vegetation, such land cannot support most forms of life.

3. Decreased Soil Fertility: The toxic chemicals present in the soil can decrease soil fertility and

therefore decrease in the soil yield. The contaminated soil is then used to produce fruits and vegetables

which lacks quality nutrients and may contain some poisonous substance to cause serious health

problems in people consuming them

.4. Toxic Dust: The emission of toxic and foul gases from landfills pollutes the environment and causes

serious effects on health of some people. The unpleasant smell causes inconvenience to other people.

5. Changes in Soil Structure: The death of many soil organisms (e.g. earthworms) in the soil can lead to

alteration in soil structure. Apart from that, it could also force other predators to move to other places in

search of food.

A number of ways have been suggested to curb the current rate of pollution. Such attempts at cleaning

up the environment require plenty of time and resources to be pitched in. Industries have been given

regulations for the disposal of hazardous waste, which aims at minimizing the area that becomes

polluted.Organic methods of farming are being supported, which do not use chemical laden pesticides

and fertilizers. Use of plants that can remove the pollutants from the soil is being encouraged. However,

the road ahead is quite long and the prevention