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Do you want to create an amazing science fair project on water pollution ? You are in the right place. Read the below given article to get a complete idea on global warming: 1. Meaning of Global Warming 2. Environmental Threats Posed by Global Warming 3. Consequences 4. Effects 5. Impacts 6. Approaches 7. Prevention and Control.
Contents:
- Science Fair Project on the Meaning of Global Warming
- Science Fair Project on the Environmental Threats Posed by Global Warming
- Science Fair Project on the Consequences of Global Warming
- Science Fair Project on the Effects of Global Warming
- Science Fair Project on the Impact of Global Warming
- Science Fair Project on the Approaches to Deal with Global Warming
- Science Fair Project on the Prevention and Control of Global Warming
Science Fair Project # 1. Meaning of Global Warming:
Global warming is the increase in the average temperature of the Earth s near-surface air and oceans through greenhouse gases being pumped into the atmosphere from tailpipes and smoke stacks.
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It is now well established that average air temperatures are increasing all over the world. It has been observed that decade of the 1990s was the warmest ever recorded. It appears that average temperatures are rising continuously.
Since the end of the nineteenth century, global mean temperature has risen by small amount of 0.5°C. The rise in temperature seems to be insignificant, however, it can have significant impact on the earth’s climate. The concentration of CO2 and other gases has increased worldwide. These gases trap the heat from the sun.
Then the gases trap heat like the glass in a greenhouse. This is where the term the “green house effect” came from.
Global average air temperature near the Earth’s surface rose 0.74 ± 0.18°C (1.3 ± 0.32°F) during the past century. According to NOAA, the global warming rate in the last 25 years has risen to 3.6 degrees F per century, which tends to confirm the predictions of temperature increases made by international panels of climate change (IPCC) scientists.
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They also conclude, “most of the observed increase in globally averaged temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations. This leads to-warming of the surface and lower atmosphere by increasing-the greenhouse effect.
The term “Green House Effect” was first coined by J. Fourier in 1827. The effect is also called as “Atmospheric Effect”, Global Warming.
Human activities are changing the composition as well as behaviour of the atmosphere at an unprecedented rate. The pollutants from a wide range of human activities are increasing the global atmospheric concentration of certain heat trapping gases, which act like a blanket, trapping heat close to the surface that would otherwise escape through the atmosphere to the outer sphere.
This process is known as greenhouse effect, because it reminds some observers of the heat trapping effect of the glass walls in a horticultural greenhouse.
In a green house, visible light passes through the glass and heats up the soil, warming the plants. The warm soil emits radiation in longer wavelengths, particularly in the infra-red. Because glass is opaque to longer wavelength of infra-red radiation, it partly reflects and partly absorbs infra-red radiation. This mechanism keeps the green house warmer than the outer atmosphere.
Thus a green house is that body which allows the short wavelength incoming solar radiation to come in but does not allow the long wave outgoing terrestrial infra-red radiation to escape.
In a similar way, the earth’s atmosphere bottles up the energy of the sun, and is said to set like a ‘green house’, where CO2 acts like glass windows. CO2 and water vapours in the atmosphere transmit short wavelength solar radiation but reflect the longer wavelength heat radiation from warmed surface of the earth.
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CO2 molecules are transparent to sunlight but not to the heat radiation. So they trap and re-enforce the solar heat stimulating an effect which is popularly known as greenhouse effect.
The Greenhouse effect may therefore be defined as “The progressive warming up of the earth’s surface due to blanketing effect of man-made CO2 in the atmosphere.” The four major greenhouse gases, which cause adverse effects are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O) and chlorofluorocarbon (CFCs).
Among these CO2 is the most common and important greenhouse gas. Here it should be noted that ozone and SO2 also act as serious pollutants in causing global warming. The other greenhouse gases such as methane and chlorofluorocarbons contribute about 19 % and 17 % respectively to the global warming.
Science Fair Project # 2. Environmental Threats Posed by Global Warming:
(a) Rise in the global temperatures will result in melting of the ice masses in the Arctic and Antarctica regions, resulting in rising of the sea level.
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(b) With the consequence there would be submergence of many low lying coastal areas.
(c) Flooding of the coastal areas will cause massive soil erosion and siltation, contamination of water and water borne diseases.
(d) In temperate regions, the summers will be longer and hotter whereas in the winters will be shorter and warmer.
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(e) The already dry sub-tropical regions may become drier and the tropical regions may become wetter.
(f) Desertification, droughts and famine would lead to migration of population and new urbanisation.
(g) Due to increased concentration of carbon-dioxide the growth and yield of plants will increase resulting in rapid depletion of nutrients from the soil.
(h) Disruption of the ecosystem by increase in rainfall (9% – 10 %), altered crop patterns and adverse effects on flora and fauna.
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Toward off the menace of carbon emissions, the dependence of fossil fuel need to be reduced by encouraging the use of non-conventional sources of energy like solar energy, bio-gas, wind and hydro power etc. Besides controlling grazing and hacking afforestation and reforestation should be encouraged because forests act as carbon dioxide sinks and helps to reduce the CO2 concentrations and thereby reduce the Green House Effect.
Science Fair Project # 3. Consequences of Global warming:
1. Climate change – Concentration of CO2 600 ppm,
a. Increases in temperature. Melting of pole’s Ice,
b. Level of sea water rises.
2. Resulting in human diseases – Spread of Malaria,
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3. Elephantiasis,
4. Communicable diseases,
5. Schitosomiasis,
6. Impact on agriculture – Change in climate on crops,
7. Lives stock pests,
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8. Soil, water supplies.
Science Fair Project # 4. Effects of Global Warming:
The adverse effects of global warming are under mentioned:
(i) Effect of Global Warming on Earth’s Climate:
In 1890s, many scientists in Sweden and United States discussed about the problems of carbon dioxide concentration in the atmosphere, which was likely to increase through the combustion of coal. Now the increase in carbon dioxide has brought about global warming.
Global warming may be referred to as global climate change. It is unfortunate that man has been treating the atmosphere as a dumping ground for the pollutants. Moreover, we have not been able to predict the adverse impact of the concentration of these pollutants in the atmosphere.
Several workers have studied the impact of these pollutants on the environmental factors. It has been noticed that average temperatures have slightly increased during the first four decades of the last century.
Global warming has emerged as the most serious environmental threat of the 21st century. Data collected so far indicate that the temperature of the earth has increased by 0.5°C over the past century, mainly due to the accumulation of green house gases. Initially CO2 thought to be exclusively responsible for green house effect, is now known to cause only half the problem.
The rest comes from other gases like chlorofluoro carbons, nitrous oxides and methane. Carbon dioxide is added to the atmosphere both naturally and unnaturally. Naturally through volcanoes and unnaturally as a result of human activity.
About 200 years ago, CO2 was added to the atmosphere by only natural processes sufficiently to be absorbed by forests and oceans. But after the industrialisation, coal burning factories started releasing CO2 faster than the forests and oceans absorb CO2.
(ii) Effects on Weather and Climate:
The global mean temperature has increased about 0.6°C in the twentieth century. It is thought, that mean global temperature may increase by 1.4 to 5.8°C by the end of twenty first century (i.e., 2100 AD).
The projected change in mean surface temperatures may appear insignificant because variations of this magnitude are experienced in course of seasonal or even daily weather. The world climate was very much different from what it is today. The transition from the great Ice Age to present-day climate during which average surface temperature rose by 5°C took about twelve thousand years.
But the variations of almost similar magnitude shall be experienced within a course of single century if greenhouse gases continue to rise at the present rate. The rise in global temperatures would not be uniform all over the surface area of the earth. Temperature changes are expected to be most marked in regions of middle and higher altitudes.
It is thought that polar regions of the world would undergo larger increase in temperature, about ten to twelve times as much as the tropics. This shall bring unprecedented changes in wind and precipitation patterns within a span of a single century.
Warming of atmosphere will considerably increase its moisture carrying capacity. While the troposphere warms up, the stratosphere will cool down. Precipitation is expected to increase at higher latitudes in both summer and winter and in southern and eastern Asia in summer.
The effect of global warming on agriculture will be of varied type in different parts of the world. Wheat and maize crops may suffer from moisture stress. More fertilizers shall have to be used to sustain productivity.
The climate change will increase threats to human health, particularly in tropical and sub-tropical regions of the world, due to change in ranges of disease vectors, water-born pathogens, etc. Global warming shall bring with it an entirely new environment in which life though not impossible yet its existence shall be tougher to maintain.
(iii) Sea Level Change:
Though there are so many uncertainties regarding the consequences of global warming, one of the obvious results of the general heating up of earth’s surface shall be a rather rapid rise in mean sea level. Evidences suggest that in Ice Age, about 12,000 years back it was nearly 100 m lower than the present-day level.
It is expected that global rise in temperature shall further enhance the rate of already rising sea level in two ways:
(i) Large deposits of ice present on earth’s surface shall melt, which will add more water to the oceans.
(ii) Rise in temperature shall also cause thermal expansion of the upper layers of the water.
Sea level has been raised by 1 to 2 mm per year during the twentieth century. It is expected that by the end of twenty first century (i.e., 2100 AD.), the global mean sea level can increase up-to 0.88 m over the 1990 level. A rise of even half a meter in sea level would largely effect human population, one-third of which lives within 60 km of a coastline.
Thus, many of the world’s important cities and coastal areas will come under the threat of flood, and several low-lying islands will be submerged.
The flooding of coastal salt marshes and estuaries will deprive many important birds and fish their breeding grounds and their extinction will be imminent.
Thus, sea-level rise is predicted to have negative impacts on human settlements, such as tourism, fresh-water supplies, fisheries, wetlands, etc.
(iv) Effects on Distribution and Phenology of Species:
As the climatic belts shift away from equator towards poles, vegetation will also shift in the same direction to stay in favourable climatic conditions. Those species, which will not do so shall die. There will be losses of genetic resources on large scale.
Only hardy and resistant forms shall come up and survive. For example, with a global temperature rise by 2 to 5°C during the twenty first century, the temperate region vegetation may shift 250-600 km poleward.
As trees are more sensitive to temperature stress, a rapid rise in temperature may cause large scale death of trees and there replacement by scrub vegetation.
As temperature changes will affect wind and precipitation patterns also water could play an important role in altering the biotic communities.
It has been suggested that some rise in precipitation, however, shall be balanced by an enhanced evaporation and this could lead to water deficit and moisture stress in many regions of the world. Insects and pests may increase as warmer conditions could be more favourable to their growth and coupled with higher humidity pathogens shall multiply.
(v) Food Production:
Increased temperature will cause eruption of plant diseases and pests. Besides, there will be explosive growth of weeds and increased basal rate of respiration of plants. Thus, all these factors will be responsible for decrease of crop production.
However, small temperature increase may slightly enhance crop productivity in temperate regions, but larger temperature changes will reduce crop productivity there also.
Even a small rise in temperature will have detrimental effect on crop-productivity, both in tropical and sub-tropical regions.
It is expected that rice yield alone, in south-east Asia will go down by 5 per cent for each 1°C rise in temperature. However, in spite of beneficial carbon dioxide fertilization effect, the overall world crop productivity will decline considerably due to projected global warming, and the food supply of the whole world shall be affected.
As the climatic belts will shift away from equator towards poles, vegetation will shift in the same direction to stay in favourable climatic conditions. Those species which shall be unable to do so, they will die.
There will be losses of genetic resources on large scale. Only hardy and resistant species shall come up and survive. An altogether changed biotic spectrum shall replace the earlier ones and almost all important biomes shall be affected.
Alterations in cropping pattern shall occur and pest resistant varieties more suitably to warmer conditions shall have to be developed. In brief greenhouse warming (global warming) shall bring with if an entirely new environment in which life though not impossible yet its existence shall be tougher to meet with.
Science Fair Project # 5. Impact of Global Warming:
Some of the impacts of global warming are:
i. Rise in Sea Levels:
This is a major consequence of global warming arising out of green house effect.
Four major changes may take place as a consequence of the rise in temperature:
(i) Mountain glacier melting,
(ii) Greenland ice sheet melting,
(iii) Antarctic ice sheet melting, and
(iv) Thermal expansion.
Since oceans act as reservoir of heat, it would result in rise of sea level by as much as 2 metres due to expansion of sea water. This rise of the sea level due to the above and also due to the melting of glaciers, ice caps of Greenland and Antarctica, would threaten coastal countries.
Some 60 odd island nations, like Maldives, Bangladesh may totally get submerged. In India, coastal areas such as Chennai and Goa would also meet with a similar fate. In these above affected areas the building technology and conditions for road and pipeline constructions would alter.
ii. World Food Production:
A slight increase in surface temperature of about 1°C can adversely affect the world food production. For example, wheat growing zones in the northern latitude will be shifted from Russia and Canada to the poles. The northern pole will thus shift from fertile to poor soils.
The US would also produce less grain. At the same time the productivity of the oceans would also decrease due to warming of the surface layer, which, in turn, would reduce the nutrients transport from the deeper layers to the surface, through vertical circulation.
On the other hand, North and East Africa, the Middle East, India, West Australia and Mexico would be warmer and wetter, enabling them to produce more grains. An increase of 60-80 per-cent crop yield has been predicted. There is also a prediction of regional climatic changes along the ecosystem.
This climatic change is likely to be beneficial, due to dominance of C3 crops such as barley, wheat, rice and soya beans. This enhanced production would also receive a boost as the C4 plants (comprising of weeds) will not be directly benefitted from the CO2 fertilisation (that is, increase in CO2) effect. The potentially limiting factors would include changes in insect life cycles and an increase in the survival, growth and spread of pathogens.
iii. Water Balance:
It has been predicted that in future, warmer world will have water crisis in some parts, while other regions will be wetter than today. The problems of water availability in drier areas are likely to be serious and more perhaps would be more expensive to solve.
iv. Human Health:
Recently there are reports of spreading of diseases due to climactic changes. As the globe will become warmer, there is every likeliness that more and more people would be affected by tropical diseases in the years to come.
v. Other Effects:
(i) As winters would be warmer there would be a decrease in the cost of heating.
(ii) An increase in air-conditioning cost would take place as summers would be prolonged and more hotter.
(iii) Much easier navigation and for a longer period during the summer in the Arctic seas.
(iv) Easier conditions for offshore oil and gas development.
(v) Coral reefs in 32 countries have experienced dramatic bleaching in 1997 to 1998. Bleaching is due to the loss of microscopic algae that both colours and nourishes living corals. Water that is warmer than normal by 2° to 3°F has been linked to bleaching.
It is seen that although CO2 (and other greenhouse gases) constitutes only a fraction of the atmospheric gases (0.03%), it however, plays an climate-important role in changing the global climate and affecting other drastic changes. It is thus, essential that the greenhouse gases be kept under control.
The problem is that, the developing world do not have economic resources and they are responsible for the discharge of 2/5th of the global carbon emissions each year, which is increasing by over 100 million tonnes a year. The UNEP has indeed chosen the appropriate slogan “GLOBAL WARMING: GLOBAL WARNING” to alert the people on world Environment Day, June 5, 1989.
Estimate the Impact of Global Warming:
General Circulation Models (GCM) have been developed by using sophisticated computer programmes. This is one of the best methods to estimate the impacts of global warming. As a basis for predicting future global impacts, most models assume that the concentration of green house gases is likely to double than their present level.
Most of the models predict an average global warming up to 4.2°C, and an overall increase in the precipitation of about 10 per cent by the year 2050. It is also expected that global warming will create more active hydrological cycle, increasing cloudiness as well as precipitation.
If the average global temperature continue to rise, then two important potential impacts of global warming include the effects on sea levels and on the ecosystems. Recent estimates suggest that global sea level has risen by about 15cm during the 20th century, with most of the rise occurred since 1930.
Some scientists believe that because of green house warming, average sea level may rise by at least 30cm and as much as 1.4m by the year 2030. This is likely to cause extensive instability in the economic and social life in the coastal areas throughout the world.
Science Fair Project # 6. Approaches to Deal with Global Warming:
Some strategies which could reduce the global warming are as follows:
(i) Reduction of the greenhouse gas emissions by the use of limited fossil fuels, by developing alternative renewable sources of energy, such as solar energy, wind energy, etc.
(ii) By increasing the vegetation cover, particularly the forests, for photosynthetic utilisation of carbon dioxide.
(iii) By using minimum nitrogen fertilisers in agriculture, so that, the N2O emissions may be reduced.
(iv) By developing substitutes for chlorofluorocarbons (CFCs).
Besides, above mentioned strategies, adaptations to address localised impacts of climate change shall be important.
Science Fair Project # 7. Prevention and Control of Global Warming:
Prevention:
(i) Drastic cut in the consumption of fossil fuels.
(ii) Technical alteration in industrialization and transportation.
(iii) Use of Methanol in automobile
(iv) Use of solar energy, Biogas.
(v) Forestation.
Control:
(i) Cutting down the use of fossil fuels.
(ii) Improving energy efficiency.
(iii) Reducing deforestation.
(iv) Planting trees and slowing down the growth of human population.
(v) International initiatives are also being taken to curb the emission of greenhouse gases.