Project Idea

Motivation:

A few minutes of an ambulance being stuck in traffic could prove costly to someone struggling for his life and cause the ultimate irreparable damage.

Proposal:
Building a wireless communication system between ambulances and traffic lights. When the ambulance arrives within a threshold distance of the traffic lights it sends a wireless signal to the traffic light which causes it to turn green and all other dependent signals to change colour accordingly. This prevents a traffic jam situation along the path of the ambulance.

Benefits:

1) If effectively implemented, this could prove to be a life-saving mechanism in many situations.
2) This could also significantly reduce noise pollution by lowering the need for a siren.

Drawbacks:

1) The traffic signal which detects the approaching ambulance should coordinate with dependent traffic signals.
2) This system should not be misused for other purposes and must be properly licensed.

Pallikaranai and Vandalur

A few days before the field trip, we were told about the Pallikaranai wetlands by a wildlife photographer. A wetland is defined as ‘lands transitional between terrestrial and aquatic systems where the water table is usually at or near the surface or the land is covered by standing water that does not exceed 6 meters’. They are very important, life-supporting ecosystems that have sustained human lives and communities. Locally known as Kazhiveli (a generic Tamil name for Marshes and swamps), the  Pallikaranai Marsh drained about 250 sq. km, through two outlets viz. the Okkiyam Madavu (channel) in Okkiyam thuraipakkam and the Kovalam Creek.  Draining, here, refers to flood mitigation, ground water recharge and irrigation.
We were shown pictures of the Pallikaranai Marshland as it was a few years back and now. There was a visible degradation in the quality of the ecosystem. The Marshland which is also a home to a large variety of bird-life is slowly becoming unfit for their habitation. We saw the Marshland being used for dumping wastes. The slum-dwellers who reside in the area are also adversely affected due to bad quality of the surroundings as we saw in the pictures.

There are several efforts being undertaken to restore the ecosystem to its original state. We realized that the need for these measures is high and that they need to be implemented as strictly as is possible in order to preserve one of the last recognized marshlands of the country.
This was followed by a visit to the Vandalur Zoo where we were able to spot a variety of indigenous as well as exotic species. Some of the facts mentioned about the animals really interested me. For instance, two birds belonging to a stork species were said to be “made for each other” because one’s death would cause the other to pine away until its own demise. The trip thus proved to be an educational as well as a recreational day-out with the entire class which I thoroughly enjoyed.

Vertical Farming - Does it stack up?

Vertical Farming is an idea that was born in the year 1999 in a Columbia University classroom when Dickson Despommier, a professor of environmental sciences and microbiology shared the idea with his students. According to New York magazine, nearly all the land that could potentially be farmed is already being farmed on. So Despommier proposed a novel idea of having skyscrapers filled with floor upon floor of orchards and fields producing crops all year in cities all over the world. Creating more farmable land out of thin air to meet the growing demand as a result of population explosion is virtually an impossibility and therefore this idea has inspired plenty of research by people who believe it might actually stack up. Despommier and his class made the first outline of a vertical farm in 2001. This technique is expected to prove advantageous in several ways. Firstly, transport costs and carbon dioxide emissions associated with moving food over long distances are greatly minimized. The spoilage that occurs inevitably along the way is also reduced. According to UN’s Population Division, by 2050, around 70% of the world’s population will be living in urban areas. So it’s more benefitable to have farms closer to where everyone will be living. The use of pesticides, herbicides and fungicides can be kept to a bare minimum by growing plants indoors in a controlled environment. Erosion will not be a problem because the food will be grown hydroponically. Clever recycling techniques will be used to ensure that only a fraction of the amount of water and nutrients will be needed and there will be no problem with agricultural run-off. Opponents question the potential profitability, availability of less light due to the extreme angle and pollution. Despite these drawbacks, vertical farming is thought of to be the future of sustainable farming.

Long Weekend (2008)

Long Weekend is a remake of a 1978 Australian thriller which tries to show people how nature bites back twice as hard when you disrespect it. The story revolves around a couple, Peter and Carla who decide to spend their weekend in a remote beach to repair their marriage. Also known as Nature’s Grave, the couple is shown to have a complete disregard for nature in several ways. For instance, after hitting a baby kangaroo while driving, Peter is shown to worry more about the damage to his headlights. The careless disposal of a cigarette sets a bush on fire. Peter fires at a bunch of ducks just for fun and also steals eggs from an eagle’s nest. Nature’s comeback to this attitude of the couple is rather extreme. The eagle whose nest was raided attacks Peter and he is pecked and clawed by the bird. Peter’s spear gun goes off on its own and almost hits Carla. They’re harassed by ants and dead creatures such as seagulls keep washing up ashore. They see a dark shape out in the water stalking them. They fire randomly at it and a large pool of blood is seen around the shape and the next day they realize it’s a dead sea cow when it washes up on the beach. Each ensuing day, the sea cow’s carcass moves closer to them than where it washed up and one day they wake up to find it in the middle of their camp. They panic and this not only physically affects them but also puts their nerves on edge. The tension between them increases and they constantly bicker. They split paths and Peter spends a night in the scary woods stalked by a bunch of Kangaroos. Carla, meanwhile, is not able to get out of the woods and drives in circles until she smashes into a tree. Peter wakes up the next day to find the sea cow carcass right next to him. He panics and runs through the woods past snakes and more peril and finds Carla’s body run through with a spear from his spear gun and several days dead. He reaches the road and tries to flag down a cab but the eagle from the beach flies into the cab and distracts the driver long enough to make him lose control and hit Peter bringing a karmic end to his life. The story thus, aptly justifies the title, Nature’s Grave as Nature unleashes its wrath and fury on those that disregard it.

An Inconvenient Truth - A review

An Inconvenient Truth, was a very inspirational effort by former US Vice president Al Gore’s campaign to educate the people of the world about the various looming threats that question our survival on Planet Earth…most importantly…Global Warming. His main objective was to completely rubbish the common misconception that "the Earth is so big; we can't possibly have any lasting, harmful impact on the Earth's environment."

Gore, through this documentary, has found an effective way to put the message across. At no point does he lose the audience’s attention and also adds a comic element to do so despite the fact that the issue he’s addressing is very grave. For instance, he narrates an incident from his schooling days when his teacher rubbished his classmate’s question about continental drift as ‘ridiculous’ but ultimately went on to become a science advisor in the then administration. He ties this to the fact that people assume our planet to be so big that they can’t visualize something as bizarre as movement of the continents to have ever happened just the way they think they do not contribute in any appreciable way to environmental crisis. At the same time, he talks about his college professor, Roger Revelle who was the first person to have the idea to measure the amount of carbon dioxide in the earth's atmosphere. The measurements he showed the class after his many experiments proved startling to Gore and is what sparked his interest in the issue. Gore presents to us many charts and statistics collected by environmental scientists all over the world that speak out that Global Warming is very much a reality. For instance, he shows us pictures of receding glaciers and warns us about the possibility of the collapse of a major ice sheet in Greenland or in West Antarctica, either of which could raise global sea levels by approximately 20 feet, flooding coastal areas and producing 100 million refugees.

He talks about how he lost his sister to cancer and almost lost his son in a near-fatal accident. He says these incidents brought into his focus how we take things for granted and how much losing something precious to us would hurt us. He says this suffering is what our future generations would have to endure if we do not find means to put an end to environmental degradation. He says this makes the issue a MORAL one and thereby concludes by showing us all the small ways in which we can help and charting out how much of a difference it would make for us to accept this truth, inconvenient as it may be, and doing our part to sustain life on this beautiful planet.

GM Cocoa Bean

The cocoa tree (Latin - Theobroma Cacao, which translates to “food of the gods“) only grows in humid, tropical climates, with sufficient rainfall and its cultivation limited to regions between 20° north and 20° south of the equator. The cocoa bean is the dried and fully fermented fatty seed of the cocoa tree. The leading producers are the Ivory Coast, Ghana, Indonesia and Brazil. The seeds of the cocoa tree (Theobroma cacao) are fermented together with the fruit, so developing the typical cocoa aroma. The cocoa beans are then dried, roasted, dehulled and broken. Further processing of the cocoa beans yields a cocoa paste, which after further handling is separated into:

· Dark-brown cocoa powder, which is the basis for chocolate and chocolate products of all types, such as chocolate-containing sweets, ice cream and drinking chocolate;

· Cocoa butter (vegetable fat), a high-value soft fat that is used in chocolate coatings, chocolates and nougat. Cocoa butter is also used in the pharmaceutical and cosmetic industries to manufacture products such as ointments, lotions and lipsticks.

Research and Development in the field of Gene technology aims to improve its agronomic traits such as resistance against pathogens (fungal resistance and virus resistance), resistance against pests (insect resistance), plant development (increasing yield) and quality traits (modifying fat composition of the cocoa butter). The cocoa bean has also bean enriched with new components. For instance, the creation of the perception of a sweet taste of cocoa has been done through the insertion of the gene of a sweet-tasting African plant (Thaumatococcus daniellii) which causes the cocoa plants to produce the sweetener thaumatin.

DNA experts are working with sweet giants Mars to create genetically modified chocolate that fights heart disease and diabetes and won’t make you fat. It took two years to disentangle the cocoa tree’s 420 million units of DNA. And they claim that in another five, they could unlock the secret of how to make chocolate healthy. The scientists say the secret lies in the genetic code of the cocoa bean. The beans contain chemicals called flavonols which lower blood pressure and help keep the heart healthy. And the scientists believe they can change the DNA of the cocoa tree so it produces beans with far higher levels of flavonols. They also hope to produce beans that fight diabetes, as well as making the fat in cocoa much healthier.

Sources:

http://www.gmo-compass.org/eng/database/plants/43.cocoa.html

http://www.infiniteunknown.net/2010/11/20/scientists-working-to-create-genetically-modified-chocolate-to-make-you-healthy-sure/

Animal Testing

The use of non-humans for testing of various products is known as animal testing. People for the Ethical Treatment of Animals (PETA), is a group that believes that animal tests are not only extremely cruel but also pointless. According to them, they are completely inaccurate because of the vast physiological variations between species. They believe that animal studies teach us nothing about the health of humans because human reactions to illnesses and medications are completely different from the reactions of other animals. Other species absorb, metabolize and eliminate substances differently than humans do. They believe that testing on animals is just plain bad science which harms humans and other animals alike. 

Even though no law in any country requires cosmetics or personal-care products to be tested on animals, many companies around the world choose to subject animals to painful. Two of the most common animal tests conducted to this day are eye irritancy and lethal dose tests by several cosmetics companies such as Pantene, Sunsilk, Dove etc.

In eye irritancy tests, chemicals are dripped into the eyes of albino rabbits, who have no tear ducts, which makes them unable to cry to wash away the toxic chemicals. After placing the chemicals in the rabbits' eyes, laboratory technicians record the damage to the eye. Often, the rabbits receive no anaesthesia during the tests. Many rabbits break their backs as they struggle to escape the pain.

In acute toxicity tests, increasing amounts of detergent, eyeshadow and other products are force-fed to rats, mice, rabbits, guinea pigs and other animals until a certain percentage of them are poisoned to death. The infamous Lethal Dose₅₀ (LD₅₀) test is the most common form of animal-poisoning study. It is used to determine what concentration of a substance is needed to kill 50 per cent of a group of animals. A study found that these tests were able to predict toxicity in humans with only 65 per cent accuracy.

There are several humane alternatives to animal testing:

      1.      Instead of measuring how long it takes a chemical to burn away the cornea of a rabbit's eye, manufacturers can now drop that chemical onto donated human corneas.

      2.      Human skin cultures can also be grown and ordered for irritancy testing.

      3.      In addition, companies can use computer and mathematical models.

      4.      They can also choose to use ingredients and chemicals which have already been proved to be harmless and are known to be safe.

 

      Source: www.petaindia.com

Kitply Plywood

Plywood is probably the most popular, versatile, strong and flexible man-made woodworking material used for building furniture and cabinetry. Plywood is a laminated product made up of numerous thin strips of wood laid in alternating directions and bonded with glue into strong, stable sheets. Because of the way in which plywood is constructed, it also resists cracking, bending, warping, and shrinkage, depending upon its thickness. Kitply is among the first Indian companies to include commitment to environmental protection as one of its corporate objectives. Tree plantation is a regular and committed activity at Kitply spread over an area of 1000 acres in factories and residential townships. Kitply Industries has the following Environmental Policy: Through its endeavors to develop more effective ways and methods to conserve our natural resources, Kitply Industries is determined to fulfill its responsibility of beautifying and protecting the natural ambience that surrounds us by enhancing the awareness of its employees. Kitply Industries conserve energy and resources in all its activities. It promotes the development of products and technologies that minimize environmental impact, while at the same time taking into account the maintenance of people's safety and health. It strives to safeguard the safety and health of local citizens, together with those of its employees.

Production of tree crop on degraded wasteland successfully was its main objective to take up Agro Forestry Project in 1994 (around Raipur of Madhya Pradesh now known as Chhatisgarh).

The Agro Forestry Project shall:

     · Create massive employment opportunities among the rural poor.

     · Reduce pressure on natural forests for fuel, fodder and commercial timber.

     · Prevent top soil erosion, improve water holding capacity of the soil and recharge underground water and provide clean environment.

     · Utilize hazardous industrial waste such as fly ash and sewage sludge for development of waste lands

Source: www.kitply.com

National Mineral Development Corporation

Since its inception, the National Mineral Development Corporation has been involved in the exploration of wide range of minerals including iron ore, copper, rock phosphate, lime stone, dolomite, gypsum, bentonite, magnesite, diamond, tin, tungsten, graphite, beach sands etc. They have a strict corporate policy for environmental management. They intend to:

1) Create sound and eco-friendly environment for sustainable development at all production projects
2) Plan new projects with environment – friendly considerations
3) Plan regulative, ameliorative and mitigative measures to protect environment
4) Lend support to projects on environmental matters

The Environmental Policy is framed specifically to fulfill the following objectives:

1) Create a work environment which enhances/ motivates production and productivity.
2) Create a residing environment for the enjoyment & peace of employee.
3) Encourage safe and scientific mining and other engineering practices.
4) Promoting awareness amongst the employees and the neighbourhood population for adopting environmentally acceptable procedures and restricting environmental degradation and pollution to the barest minimum.
5) Establishing "Eco-label" for its finished products so as to promote domestic and international markets.
6) To achieve Communal harmony and peace amongst the employees and the local villagers for heading fast towards "sustainable development".
7) Meaningful use of forest lands within the lease areas.
8) Restoration of the post mining land use to the pre-mining status, to the extent possible.

NMDC has specially appointed officers to monitor the environmental performances and guide the Projects for maintaining good environmental practices and to adopt newer, safe and cleaner technologies. They also started afforestation on a planned pattern in consultation with Divisional Forest Officer (Social forestry) of concerned areas with the objectives such as increasing the density around the project & township, stabilization of degraded lands & waste dumps for preventing soil erosion, rehabilitated of mined out areas, improving the condition of the catchment areas and stream courses and aesthetic look of the township areas.

Source: www.nmdc.co.in

STRUCTURE OF THE ENVIRONMENT

Environment, Ecology and Ecosystem are three different terms. But they are interrelated. The natural surroundings of an organism, both living and physical is its environment. The physical component consists of air, water, light, land etc. The biotic component consists off all the living organisms surrounding us. Scientists believe that natural environment is a better word to use given the common use of the word environment. Ecology is a branch of study of the interrelationships with the organism and its environment. It is a basic fact that the Earth includes a large variety of living things which depend in some way on other living and non-living things. This study of how the existence and activity of organism influences its environment and the vice versa is ecology. Ecology involves collecting information about organisms and their environment, looking for patterns, and seeking to explain these patterns. The ecology that takes place in a defined area is called ecosystem. Ecosystem is a functional unit of dynamic system of organisms interacting with each other (biotic) and the inanimate environment (abiotic).

The structure of the environment can be depicted as follows:
 

All components of environment are closely related and interact with each other.

Though air, water and land are the components of environment, the Britishand American scientists put in two different manners.

1.Components of Environment as per British literature

Here the components are classified in terms of biotic and abiotic based uponlife. The biotic components are further listed as producers, consumers anddecomposers and the abiotic components are classified as climatic(water, air)and edaphic(land). It is from this component system that the study of structureof ecosystem was evolved.
The biotic components of an ecosystem are the living organisms that exist in the system. These organisms can be classified as producers, consumers or decomposers. Green plants prepare complex organic food using abiotic factors like carbon dioxide and water in the presence of sunlight by a process vital to survival of life on earth – Photosynthesis. Green plants are used by herbivores and the herbivores are in turn consumed by carnivores (secondary consumers) which are then consumed by tertiary consumers which constitutes what is known as food chain. Thus all living beings obtain food from plants directly or indirectly. After the death of all these organisms, decomposers decompose complex organic substances of their body into simple inorganic forms. These are again absorbed by the green plants and this forms a cycle.
The abiotic components of an ecosystem are the non-living features of the ecosystem that the living organisms depend on. Each abiotic component influences the number and variety of plants that grow in an ecosystem, which in turn has an influence on the variety of animals that live there. The way in which plants and animals grow and carry out their different activities is a result of several abiotic factors. These factors are light, temperature, water, atmospheric gases, wind as well as soil (edaphic) and physiographic (nature of land surface) factors. Light energy (sunlight) is the primary source of energy in nearly all ecosystems. It is the energy that is used by green plants (which contain chlorophyll) during the process of photosynthesis The distribution of plants and animals is also greatly influenced by extremes in temperature for instance the warm season. The occurrence or non-occurrence of frost is a particularly important determinant of plant distribution since many plants cannot prevent their tissues from freezing or survive the freezing and thawing processes. In animals, a distinction is made between ectothermic ("cold-blooded" or poikilothermic) animals and endothermic ("warm-blooded" or homothermic) animals. Plant and animal habitats vary from entirely aquatic environments to very dry deserts. Water, which forms the hydrosphere, is essential for life and all organisms depend on it to survive especially in desert areas. The atmosphere also plays a critical role in sustaining life on earth. The most important gases used by plants and animals are oxygen, which is used by all living organisms during respiration, carbon dioxide, which is used by green plants during photosynthesis and nitrogen, made available to plants by certain bacteria and through the action of lightning. Winds or air currents arise on a world-wide scale as a result of a complex interaction between hot air expanding and rising (convection) in the mid-latitudes. This has various effects on the rotation of the earth and results in a centrifugal force which tends to lift the air at the equator. This force is known as the Coriolis force and tends to deflect winds to their left of the southern hemisphere and to the right in the northern hemisphere. Winds carry water vapour which may condense and fall in the form of rain, snow or hail. Wind plays a role in pollination and seed dispersal of some plants, as well as the dispersal of some animals, such as insects. Soil (edaphic factors) factors include soil texture, soil air, soil temperature, soil water, soil solution and pH, together with soil organisms and decaying matter which plays a major role in helping plant growth as well as in providing an environment for sub-terrestrial animals. Lastly, physiographic factors refer to the factors that are those associated with the physical nature of the area, such as altitude, slope of land and the position of the area in relation to the sun or rain-bearing winds. Altitude plays a role in vegetations zones. Slopes are important when considering the temperature of the soil surface on land with a northern slope, on level and on land with south facing slopes.

2.Components of Environment as per American literature
As per American literature, the components of environment are listed as:
1.Hydrosphere(Water)
2.Atmosphere(Air)
3.Lithosphere(Land)
4.Biosphere(Flora/Fauna/Microbes)
5.Anthrosphere (man made things)

Hydrosphere:

The hydrosphere contains all the solid, liquid, and gaseous water of the planet. It ranges from 10 to 20 kilometers in thickness. The hydrosphere extends from Earth's surface downward several kilometers into the lithosphere and upward about 12 kilometers into the atmosphere. A small portion of the water in the hydrosphere is fresh (non-salty). This water flows as precipitation from the atmosphere down to Earth's surface, as rivers and streams along Earth's surface, and as groundwater beneath Earth's surface. Most of Earth's fresh water, however, is frozen. Ninety-seven percent of Earth's water is salty. The salty water collects in deep valleys along Earth's surface. These large collections of salty water are referred to as oceans. The image above depicts the different temperatures one would find on oceans' surfaces. Water near the poles is very cold, while water near the equator is very warm. The differences in temperature cause water to change physical states. Extremely low temperatures like those found at the poles cause water to freeze into a solid such as a polar icecap, a glacier, or an iceberg. Extremely high temperatures like those found at the equator cause water to evaporate into a gas. Some scientists place frozen water--glaciers, icecaps, and icebergs--in its own sphere called the "cryosphere." For the purpose of this module, however, frozen water will be included as part of the hydrosphere. The word "hydrosphere" will be used in reference to all water in Earth's system. 

Atmosphere:

 

The atmosphere contains all the air in Earth's system. It extends from less than 1 m below the planet's surface to more than 10,000 km above the planet's surface. The upper portion of the atmosphere protects the organisms of the biosphere from the sun's ultraviolet radiation. It also absorbs and emits heat. When air temperature in the lower portion of this sphere changes, weather occurs. As air in the lower atmosphere is heated or cooled, it moves around the planet. The result can be as simple as a breeze or as complex as a tornado. The atmosphere is made up of many layers namely the toposphere, stratosphere, mesosphere, thermosphere and exosphere.

Lithosphere:

The lithosphere contains all of the cold, hard solid land of the planet's crust (surface), the semi-solid land underneath the crust, and the liquid land near the center of the planet. The surface of the lithosphere is very uneven. There are high mountain ranges like the Rockies and Andes, huge plains or flat areas like those in Texas, Iowa, and Brazil, and deep valleys along the ocean floor. The solid, semi-solid, and liquid land of the lithosphere form layers that are physically and chemically different. The outermost layer of the lithosphere consists of loose soil rich in nutrients, oxygen, and silicon. Beneath that layer lies a very thin, solid crust of oxygen and silicon. Next is a thick, semi-solid mantle of oxygen, silicon, iron, and magnesium. Below that is a liquid outer core of nickel and iron. At the center of Earth is a solid inner core of nickel and iron. The word "lithosphere" can take on different meanings depending on the speaker and the audience. For example, many geologists--scientists who study the geologic formations of Earth--reserve the word "lithosphere" to mean only the cold, hard surface of Earth, not the entire inside of the planet.

Biosphere:

The biosphere contains all the planet's living things. This sphere includes al\l of the microorganisms, plants, and animals of Earth. Within the biosphere, living things form ecological communities based on the physical surroundings of an area. These communities are referred to as biomes. Deserts, grasslands, and tropical rainforests are three of the many types of biomes that exist within the biosphere. It is impossible to detect from space each individual organism within the biosphere. However, biomes can be seen from space. For example, the image above distinguishes between lands covered with plants and those that are not. Some scientists place humans in their own sphere called the "anthrosphere."

All these physical and biological factors working in tandem with cultural, social, economic and other man-made elements provide a suitable environment for sustenance of all life-forms. The manner in which they interact with each other plays a crucial role in maintaining an ecological balance.

Sources:

http://www.cotf.edu/ete/ESS/ESSspheres.html

http://www.bcb.uwc.ac.za/Sci_Ed/grade10/ecology/abiotic/abiot.htm

DROUGHT

Drought is a period or condition of unusually dry weather within a geographic area where rainfall is normally present. Droughts occur in all climatic zones. However, its characteristics vary significantly from one region to another. Drought usually results in a water shortage that seriously interferes with human activity. Water-supply reservoirs empty, wells dry up, and crop damage ensues. Its seriousness depends on the degree of the water shortage, size of area affected, and the duration and warmth of the dry period.

CAUSES

      1. Water vapor condenses only if air rises into the colder regions of the atmosphere. If the air doesn’t rise, then no rain will form. When there is high air pressure, air falls instead of rising. With the air pressing down in a high pressure zone, no currents of water vapor are carried upward. As a result, no condensation occurs, and little rain falls to earth.

      2. Most precipitation depends on water vapor carried by winds from an ocean or other source of moisture. If these moisture-carrying winds are replaced by winds from a dry region or flow in different directions, the weather is abnormally dry and often persistently cloudless.

      3. Mountains can prevent wind from blowing moisture to needed regions. As air is moving past a mountain range, it is forced to rise in order to pass over the peaks. However, as the air rises, it becomes colder and the vapor condenses into rain or snow. The rain then falls on that side of the mountain, known as the windward side (the side that is turned toward the wind). When the air mass finally makes it over the mountain, it has lost much of its vapor. This is another reason why many deserts are found on the side of a mountain facing away from the ocean. This phenomenon is known as the rain shadow effect.

IMPACTS 


a) Environmental: - Some direct impacts of drought are reduced crop and forest productivity, reduced ground water levels, increased fire hazard, increased livestock and wildlife death rates, and damage to wildlife and fish habitat. Drought is also associated with increases in insect infestations and plant disease. Forest fires increase dramatically during periods of droughts. 
b) Economic: - A reduction in crop productivity usually results in less income for farmers, increased prices for food, unemployment, and migration. 
c) Social: - Social impacts include health, public safety, conflicts between water users, and reduced quality of life. During droughts many people migrate to areas outside the drought-affected location. When this happens, the area loses a great deal of its population, and thus the area has less financial support. Between 1950 and 1980 the drought of Brazil had a loss of 5.5 million people. This continues to be a significant problem in the economic development of Brazil.

WARNING AND DISSEMINATION

There is a "Weather-Watch-Group" in the Ministry of Agriculture, which meets every week to take stock of the rainfall progress, its effects on the crops from sowing to harvesting, during the kharif season. Weekly input gives an early warning about the impending drought as and when symptoms arise in this regard and the states are warned accordingly. The drought assessment is based on a comparative evaluation of satellite observed green vegetation cover (both area and greenness) of a district in any specific time period, with that of any similar period in previous years.

PREVENTION

Although drought cannot be reliably predicted, certain precautions can be taken in drought-risk areas. It is important to develop strategies to protect from drought. Strategies for drought protection, mitigation or relief include:

1. Construction of Dams:

The construction of dams is a better choice to avoid drought. Dams work by storing the extra water when it is available, so that during a time of drought, it can be released. It is done both to prevent drought and to prevent flooding. The main purpose of most dams is to create a permanent reservoir of water for use at a later time. The dam must be watertight (i.e. impermeable or impervious to water) so that water does not leak out of the dam and escape downstream. An essential part of a dam is therefore the "impermeable membrane", i.e. the watertight part of the dam that prevents water leaking out.

2. Cloud seeding:

Cloud seeding is the process of spreading either dry ice, or more commonly, silver iodide aerosols, into the upper part of clouds to try to stimulate the precipitation process and form rain. Since most rainfall starts through the growth of ice crystals from super-cooled cloud droplets (droplets colder than the freezing point, 32 deg. F or 0 deg. C) in the upper parts of clouds, the silver iodide particles are meant to encourage the growth of new ice particles. The history of cloud seeding has experienced uncertain results because it can never be known whether a cloud that rains after seeding might have rained anyway. This is because seeding is performed on clouds that look like they have some potential for producing rain.

3. Desalination:

It is the process of removing soluble salts from water to render it suitable for drinking, irrigation, or industrial uses. The principal methods used for desalination include distillation (or evaporation), electro dialysis, freezing, ion exchange, and reverse osmosis.

4. Rainwater Harvesting:

Broadly rainwater can be harvested for two purposes

·                   Storing rainwater for ready use in containers above and below ground.

·                   Charged into soil for withdrawal later.

Rainwater harvesting can be harvested from the following surfaces 
               Roofftops.

                   Paved and unpaved areas.

·                  Water bodies.

                   Storm water drains.

The decision whether to store or recharge water depends on the rainfall pattern and the potential to do so, in a particular region. The sub-surface geology also plays an important role in making this decision.

5. Recycled water:

The use of recycled water in horticulture (urban and rural) and industry, as well as in residential areas has grown considerably over the past decade. Recycled water is water from the city or sewage that is then treated and reused. No potable water, not suited for drinking, is reused on a daily basis in some cities. It can be used for such things as car washes, laundry facilities, road cleaning, firefighting and toilet flushing. No potable water reuse is most beneficial in cities when irrigation is in full swing at ball fields, golf courses, parks, schoolyards and residential lawns. Using reclaimed water for irrigation has a marked difference on potable water levels during these months.

6. Other small scale methods:

a. Mulching

Mulches like UV stabilized poly-sheets have become the major input for growing crops. Such sheets reflect the sunlight and causes minimum soil moisture evaporation. Israel is the leading country adopting this method with very high productivity.

b. Coconut Compost

India has plenty of resources to tackle soil moisture retention like the coconut compost. When the coconut husk is composted and added to soil, the coconut fibre absorbs moisture from the soil and retails for a long period releasing moisture gradually to crops. This technology has made farming in drought prone areas very simple. Many coconut husk processing units in Tamil Nadu like Pollachi is taking advantage and exports several thousand tons of coconut compost to countries like Israel which uses as a media in green houses for growing roses, vegetables and fruits.

c. Water Aquifers

Water aquifers are made to recharge the ground water without wasting the rain water. Aquifers are simple methods of percolation by which small bore wells are dug and the inner surface is perforated and filled with gravel to absorb the rain water. The rain water percolates deep into the ground and recharges the ground water.

FAMOUS DROUGHTS

      
      1. When pione­ers headed west in the late 19th century, many couldn't resist the lure of the tall gras­sy land in the semiarid midwestern and southern plains of the United States. They settled there to farm. They were prosperous in the decades that followed, but when the 1930s rolled in, so did strong winds, drought and clouds of dust that plagued nearly 75 percent of the United States between 1931 and 1939 [source: PBS]. The era became known as the legendary Dust Bowl. The Dust Bowl brought ecological, economical and human misery to America during a time when it was already suffering under the Great Depression.

      
      2. There was a major drought in the Sahel, Africa in 1914, caused by annual rains far below average that caused a large-scale famine. As another long drought-period from 1968 through 1974 began, the grazing quickly became unsustainable, and large-scale denuding of the terrain followed. Like the drought in 1914, this led to a large-scale famine, but this time it was somewhat tempered by international visibility and an outpouring of aid. This catastrophe led to the founding of the International Fund for Agricultural Development. In June to August, 2010, famine struck the Sahel again. Niger's crops failed to mature in the heat, and famine occurred. 350,000 faced starvation, and 1,200,000 were at risk of famine.