CLIMATE CHANGE

What changes climate?

• Sun’s outputIncoming solar radiation is the main climate driver. Its energy output increased about 0.1% from 1750 to 1950, increasing temperatures by 0.2°F (0.1°C) in the first part of the 20th century. But since 1979, when we began taking measurements from space, the data show no long-term change in total solar energy, even though Earth has been warming.

• Earth’s orbit Repetitive cycles in Earth’s orbit that occur over tens of thousands of years can influence the angle and timing of sunlight.

• Volcanic eruptionsHuge volcanic eruptions can cool Earth by injecting ash and tiny particles into the stratosphere.

• Drifting continentsIn the distant past, drifting continents make a big difference in climate over millions of years by changing ice caps at the poles and by altering ocean currents, which transport heat and cold throughout the ocean depths

• Greenhouse gasesChanges in the concentration of greenhouse gases, which occur both naturally and as a result of human activities influence Earth’s climate. Greenhouse gases absorb and emit radiation within the thermal infrared range. This process is the fundamental cause of the greenhouse effect. Greenhouse gases greatly affect the temperature of the Earth; without them, Earth’s surface would average about 33 °C colder, which is about 59 °F below the present average of 14 °C (57 °F)

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Damage to coral reefs, PacificThe severity of periodic warming due to El Nino in 1997 in the Pacific led to the most serious death in coral ever known. It is estimated that about 10% of the Earth’s coral reefs were dead, another 30 % were seriously affected and another 30% were degraded. The Global Coral Reef Monitoring Network Townsville, Australia, has predicted that all the reefs could be dead by 2050.

Butterfly populations in the United KingdomGlobal warming is leading to an early arrival of butterflies in Britain. Scientists say that butterflies can now be spotted much earlier everyyear in the last two decades. Some, like the red admiral, can now be seen a month earlier than was the case in the mid – 1970s. Others, like the peacock and the orange tip are appearing between 15 and 25 days earlierthan in the past. Future rise in temperature is likely to have a detrimental effect on these butterflies. Some butterflies whichneed cooler temperatures might suffer.

CASE STUDIES

GLOBALWARMING

GLOBAL WARMING is an increase in the earth's average atmospheric temperature that causes corresponding changes in climate and that may result from the greenhouse effect.

A gradual increase in the overall temperature of the earth's atmosphere generally attributed to the greenhouse effect caused by increased levels carbon dioxide, CFCs, and other pollutants.

Since the early 20th century, Earth's mean surface temperature has increased by about 0.8 °C (1.4 °F), with about two-thirds of the increase occurring since 1980.

Warming of the climate system is unequivocal, and scientists are 95-100% certain that it is primarily caused by increasing concentrations of greenhouse gases produced by human activities such as the burning of fossil fuels and deforestation.

MORE ABOUT GLOBAL WARMING

Causes of Global Warming

Global warming is primarily a problem of too much carbon dioxide (CO2) in the atmosphere—which acts as a blanket, trapping heat and warming the planet.

As we burn fossil fuels like coal, oil and natural gas for energy or cut down and burn forests to create pastures and plantations, carbon accumulates and overloads our atmosphere.

Certain waste management and agricultural practices aggravate the problem by releasing other potent global warming gases, such as methane and nitrous oxide.

The major greenhouse gases are water vapor, which causes about 36–70% of the greenhouse effect; carbon dioxide (CO2), which causes 9–26%; methane (CH4), which causes 4–9%;and ozone (O3), which causes 3-7%. Clouds also affect the radiation balance. Human activity since the Industrial Revolution has increased the amount of greenhouse gases in the atmosphere, leading to increased radiative forcing from CO2, methane, tropospheric ozone, CFCs and nitrous oxide. 

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Effects of global warming

Sea level rise is accelerating. The planet's temperature is rising.

The number of large wildfires is growing.

Dangerous heat waves are becoming more common.

Extreme storm events are increasing in many areas. More severe droughts are occurring in others. 

These are having significant and harmful effects on our health, our environment, and our communities.

Greenhouse Gases

Nitrous oxide Carbon dioxide

Water Sulfur hexafluoride

Methane

Increasing greenhouse gases trap more heat“Greenhouse effect”

Earth’s surface absorbs heat from the sun and then re-radiates it back into the atmosphere and to space.

Increasing greenhouse gases trap more heatMuch of this heat is absorbed

by greenhouse gases, which then send the heat back to the surface, to other greenhouse gas molecules, or out to space. Though only 1% of atmospheric gases are greenhouse gases, they are extremely powerful heat trappers. By burning fossil fuels faster and faster, humans are effectively piling on more blankets, heating the planet so much and so quickly that it’s hard for Mother Nature and human societies to adapt.

How to reduce Global Warming?

Produce more fuel-efficient vehicles

Reduce vehicle use

Improve energy-efficiency in buildings

Develop carbon capture and storage processes

Triple nuclear power

Increase solar power

Decrease deforestation/plant forests

OZONE LAYER DEPLETION

The ozone layer in the upper atmosphere absorbs the sun’s ultraviolet radiation, preventing it from reaching the earth’s surface.

This layer in the atmosphere protects life on earth from the dangerous UV radiation from the sun.

In the 1970s, scientists discovered that chemicals called chlorofluorocarbons or CFCs, which were used as refrigerants and aerosol spray propellants, posed a threat to the ozone layer.

The destruction of the ozone layer is seen to cause increased cases of skin cancer and cataracts.

It also causes damage to certain crops and to plankton, thus affecting natures food chains and food webs. This in turn causes an increase in carbon dioxide due to the decrease in vegetation.

What is acid rain?

ACID RAIN is a rain or any other form of precipitation that is usually acidic i.e. it has low pH. Acid rain is caused by emissions of sulfhur dioxide and nitrogen oxide, which react with water molecules in the atmosphere to produce acids.

Causes of Acid Rain

The primary cause of acid rain is the emission of harmful gases and emissions by industrial power plants and factories, and to some extent, cars as well.

Burning of fossil fuels lead to emission of gases that give oxides of sulfur and nitrogen.

Burning of gasoline and diesel in cars build the amount of acidified water droplets in the atmosphere.

Effects of Acid Rain

The effects of acid rain are unhealthy and harmful. Buildings, national monuments and bridges tend to deteriorate faster.

The biggest reason to find satisfactory solutions

for acid rains is the damage to natural ecosystems. This rain will affect the plants, trees, rivers, lakes, soil and land wherever it may fall on.

Animals and plants that live in such areas are severely affected. Their food sources get diminished, they may develop unhealthy diseases or mutations, or they may even die in extreme cases.

The pollutants that cause acid rain—sulfur dioxide and nitrogen oxides damage human health. These gases interact in the atmosphere to form fine sulfate and nitrate particles that can be transported long distances by winds and inhaled deep into people's lungs. When we breathe in air pollution, these very fine particulates can easily enter our body, where they can cause breathing problems (asthma), bronchitis and over time even cause skin cancer.

EFFECT ON HUMANS

Solutions for acid rain•Understand acid deposition's causes and effects To solve the acid rain problem, people need to understand how acid rain damages the environment. They also need to understand what changes could be made to the air pollution sources that cause the problem.

•Use Low Sulfur Coal The amount of sulfur oxides emitted by a power plant can be reduced by burning coal with a very low percentage of sulfur present.•Use Scrubbers Scrubbers remove 80-95 percent of the sulfur oxides. Certain types do not remove nitrogen oxides. They are costly to retrofit to existing power plants. They increase the electric generating costs by 10-15 %.

NUCLEAR DISASTERS

What are Nuclear Disasters?

Nuclear energy is generated by the process of molecular fission, molcular fusion and molecular decay. Uncontrolled formation of such energy leads to nuclear disasters.

These disasters significantly affect the population and its effects are observed for years.

Effects on EnvironmentA single nuclear accident can cause loss of life, long term illness and destruction of property o a large scale.

Radioactivity leads to cancer, genetic disorders and death in the affected area for decades.

It thus affects all forms of life for generation to come.

Nuclear disasters and leakagesIn 1986 the Nuclear Power Station at Chernobyl in USSR developed a problem that led to a fire and a number of explosions in its Nuclear Reactor. The radioactive dust spread over many kilometers and covered not only Europe but North America as well. Three people died in the explosion and 28 shortly after due to radiation exposure. Some 259 sick were hospitalized. As the area had to be evacuated 1,35,000 people had to be moved immediately and another 1.5 lac by 1991. As radioactive fall out continued even more people had to be moved. An estimated6.5 lakh people may have been seriously affected. They may get cancer, thyroid tumours, and cataracts, and suffer from a lowered immune mechanism. As radioactivity passes from grass to herbivores, sheep in Scotland and Reindeer in Lapland were affected and were unfit for human consumption. Vegetable, fruit and milk were contaminated in Europe. A French Nuclear Waste Processing Center in Normandy may have affected the lives of children playing nearby. They may develop Leukemia (blood cancer) in later life.

CASE STUDY

WASTELANDRECLAIMATION

What is Wasteland?

Land that is unfit for cultivation, or is unproductive, unimproved, or barren is known as wasteland.

Land reclaimation is creation of new land where there is water.

It consists of two distinct processes: 1. One involves creating new land from sea or riverbeds. 2. The other refers to restoring an area to a more natural state(such as after pollution or salination have made it unstable).

Methods of Wasteland ReclaimationMethods of Wasteland Reclaimation

AFFORESTATION: Growing the forests over cultivable wasteland.

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.

PROVIDING SURFACE AREA: The easiest way to protect the land surface from soil erosion is to leave crop residue on the land after harvesting.

MULCHING: 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.

CHANGING GROUND TOPOGRAPHY ON DOWNHILLS: 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.

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

CHANGING AGRICULTURAL PRACTISES: Mixed cropping, crop rotation and cropping of plants are adopted to improve soil fertility.

ECOLOGICAL SUCCESSION: This refers to the natural development or redevelopment of an ecosystem which help in reclaiming the minerally deficient soil of wasteland.

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Need for wasteland development

Wasteland development provides a source of income for the rural poor.

It ensures a constant supply of fuel, fodder and timber for local use.

It makes the soil fertile by preventing soil erosion and conserving moisture.

The program helps maintain an ecological balance in the area.

The increasing forest cover helps in maintaining local climatic conditions.

TEHRI, UTTAR PRADESHNagchaund village in Tehri District of Uttar Pradesh was once an eroded and deforested land. When Soban Singh Bhandarireturned to his village after retirement from the army in 1987 he was struck by this degradation. After six months he became thepradhan of the village and decided to implement various village development schemes differently. Through the Jawahar Rozgar Yojana, he gained immense community support. In 1990 the Forest Department selected a 30-hectare barren piece of community land for a micro-watershed development program. The villagers controlled grazing in the area, undertook plantations for fuel and fodder. Bhandari helped the village raise money by selling the fodder from the area to a neighboring village and the money was used for development and maintenance work. This community effort has had a great impact onthe ecology of the area. The moisture content of the area increased and the water sources of the villages were recharged. Local people now have access to all the natural resources they need for their daily lives.

WASTE MANAGEMENT

What is WASTE?

Any material which cannot be used in the form in which it is produced is called a WASTE. It is no longer needed by us because it has lost its value. If it is thrown around, it can cause soil, air or water pollution. It also poses a serious threat to normal life, plants, animals and human beings.

INDUSTRIAL WASTES

DOMESTIC WASTES

ELECTRONIC WASTES

CONSTRUCTON WASTES

AGRICULTURAL WASTES

NUCEAR WASTES

Types of Wastes

WASTE

Basis of physical state

Solid Waste

Liquid Waste

Gaseous

Waste

Basis of degradibility

Biodegredible Waste

Non-biodegradible Waste

Effect of wastesGHGs are accumulating in Earth’s atmosphere as a result of human activities, causing global mean surface air temperature and subsurface ocean temperature to rise.

Rising global temperatures are expected to raise sea levels and change precipitation and other local climate conditions.

Changing regional climates could alter forests, crop yields, and water supplies.

This could also affect human health, animals, and many types of ecosystems.

Whether rainfall increases or decreases cannot be reliably projected for specific areas.

Waste ManagementREDUCEReduction is the best option. If we reduce at source, there is a smallerchance of waste generation and the pressure on our already stretchednatural resources is reduced.

REUSEReuse is the next best option, as the product is reused in its current form without any energy expended to convert it into a new item.

RECYCLERecycling is the last option, as although it converts a waste into a resource, it uses energy to transform that resource into a new useable product.

6. Sakshee Bhaiswar

8. Shivani Hurkat

9. Sneha Dongarwar