Here is a compilation of essays on ‘Global Warming’ for class 7, 8, 9, 10, 11 and 12. Find paragraphs, long and short essays on ‘Global Warming’ especially written for school and college students.
Essay on Global Warming
Essay Contents:
- Essay on the Introduction to Global Warming
- Essay on the Meaning of Global Warming
- Essay on the Causes of Temperature Changes (Global Warming)
- Essay on the Effects of Global Warming
- Essay on Global Warming and Solar Radiation
- Essay on Global Warming and Malnutrition
- Essay on the Politics of Global Warming
- Essay on You Can Also Reduce Global Warming
1. Essay on the Introduction to Global Warming:
The origin of global warming or enhanced heating of the atmosphere has been ascribed to the steady increase in carbon dioxide in the atmosphere over the decades – a fact firmly established by Charles David Keeling (US Scientist, considered as the father of global warming).
Carbon dioxide and few other gases, such as, methane, nitrous oxide, can absorb heat from sunlight and are known as ‘greenhouse gases’. Greenhouse gases have high global warming potential and they can stay in the atmosphere for 100 years and more.
The most significant effect of global warming is the climate change and consequent disasters. The weather is current atmospheric conditions with respect to prevalent humidity, pressure, precipitation and temperature. Climate is an average of these conditions over the years. Atmospheric temperature plays a major role in determining the climate at a particular location.
Atmosphere circulates from equator to poles in three separate closed loops, 30 degree latitude apart, which are known as the Hadley, Ferrel and Polar cells, leading to the formation of six climate zones, such as, Tropical, Dry, Temperate, Microthermal, Polar and Highland. The climatic conditions of the zone over a long period have resulted in the formation of biome with a wide spectrum of biodiversities.
With the increase in global temperature, the wind circulation cell containing hot tropical belt would expand accompanied by expansion of climate zones in this region. According to recent findings the tropical hot belt or Hadley’s cell has shown an expansion by 2 to 4.5 degrees in latitude, beyond the 1979 figures. This can lead to fundamental shift in ecosystem, biodiversity and climate.
Biomes and ecosystems are created by various climatic conditions. Forests and oceans are two major biomes and also the sinks for carbon dioxide. Biomes are dynamic entities, and prolonged environmental disruptions, such as, that caused by climate change, may alter a specific ecosystem irreversibly.
Nature’s spheres of activities, including carbon cycle, are confined to geosphere, biosphere, hydrosphere, and atmosphere. To these natural spheres, a more recent addition is anthrosphere or the areas of human activities. Anthrospheric emissions are mainly responsible for increase in greenhouse gases in the atmosphere.
Industries are here to stay & grow to cater to the increasing needs of growing populations and also to the changing life style in modern urban settings using power hungry devices. Therefore, the management objective in limiting emission is to strike a balance between anthropogenic emissions and industrial (GDP) growth.
The successive UN- sponsored conventions on climate change are held to formulate strategies on the management of global warming. Of all the conventions held so far, Kyoto Protocol has made significant contributions in the management of global warming. Kyoto Protocol have set the goals, norms and action plans to reduce directly and indirectly GHG emissions.
The signatory nations gave the commitments of time-bound programme to reduce the emission figures as stipulated in the protocol. Non signatories have resorted to voluntary emission reduction schemes. The goal is to reduce emissions from all possible sources of greenhouse gases while preserving their sinks, such as, forests, oceans and associated biodiversities. Economic incentive in terms of carbon credit has been a prime mover in reducing emissions as can be seen by the ever growing market for trading on carbon credit.
The major sources of anthrospheric emissions include power generation industries and transport systems, which are based on burning fossil fuels. Other large contributors are manufacturing industries, like, steel, cement, chemicals etc. To cater to the needs of growing population, these industries need to grow.
Large-scale deforestation and pollution of ocean water have caused shrinkage in their capacities to absorb carbon dioxide. The emission management practices adopted so far include the use of cleaner energy sources, geosequestration of carbon dioxide, adoption of energy efficient processes in manufacturing, efficient agricultural practices, waste management, preservation of major sinks like forest and ocean.
Current practice of corporate undertaking voluntary social responsibilities for cutting down the emission figures in their companies would in long run help in providing the solution pertaining to the problem of global warming without cutting down the GDP.
India’s race to become an economic power has propelled it to number three in the list of top carbon polluters by 2011. India’s greenhouse gas emissions will keep rising as it tries to lift millions out of poverty and connect nearly half a billion people to electricity grids. Government of India would introduce soon new carbon trading scheme called, called Perform, Achieve and Trade (PAT). India is starting a mandatory scheme that sets benchmark efficiency levels for 563 big polluting from power plants to steel mills and cement plants that account for 54 percent of the country’s energy consumption.
The most important challenge of this century is how to limit global warming. In evolving a techno-ecological viable solution to this burning problem it is important to know how and why it is happening and then how to control the same.
2. Essay on the Meaning of Global Warming:
Global warming is the rise in the average temperature of Earth’s atmosphere and oceans since the late 19th century and its projected continuation. 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 more than 90% 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. These findings are recognized by the national science academies of all major industrialized nations.
Climate model projections were summarized in the 2007 Fourth Assessment Report (AR4) by the Intergovernmental Panel on Climate Change (IPCC). They indicated that during the 21st century the global surface temperature is likely to rise a further 1.1 to 2.9°C (2 to 5.2°F) for their lowest emissions scenario and 2.4 to 6.4°C (4.3 to 11.5°F) for their highest. The ranges of these estimates arise from the use of models with differing sensitivity to greenhouse gas concentrations.
Future warming and related changes will vary from region to region around the globe. The effects of an increase in global temperature include a rise in sea levels and a change in the amount and pattern of precipitation, as well a probable expansion of subtropical deserts. Warming is expected to be strongest in the Arctic and would be associated with the continuing retreat of glaciers, permafrost and sea ice.
Other likely effects of the warming include a more frequent occurrence of extreme-weather events including heat waves, droughts and heavy rainfall, ocean acidification and species extinctions due to shifting temperature regimes. Effects significant to humans include the threat to food security from decreasing crop yields and the loss of habitat from inundation.
Proposed policy responses to global warming include mitigation by emissions reduction, adaptation to its effects, and possible future geo engineering. Most countries are parties to the United Nations Framework Convention on Climate Change (UNFCCC), whose ultimate objective is to prevent dangerous anthropogenic (i.e., human-induced) climate change.
Parties to the UNFCCC have adopted a range of policies designed to reduce greenhouse gas emissions and to assist in adaptation to global warming. Parties to the UNFCCC have agreed that deep cuts in emissions are required, and that future global warming should be limited to below 2.0°C (3.6°F) relative to the pre-industrial level.
Reports published in 2011 by the United Nations Environment Programme and the International Energy Agency suggest that efforts as of the early 21st century to reduce emissions may be inadequate to meet the UNFCCC’s 2°C target.
Observed Temperature Changes:
The increase in ocean heat content is much larger than any other store of energy in the Earth’s heat balance over the two periods 1961 to 2003 and 1993 to 2003, and accounts for more than 90% of the possible increase in heat content of the Earth system during these periods.
The Earth’s average surface temperature rose by 0.74 ± 0.18°C over the period 1906-2005. The rate of warming over the last half of that period was almost double that for the period as a whole (0.13 ± 0.03°C per decade, versus 0.07 ± 0.02°C per decade).
Climate proxies show the temperature to have been relatively stable over the one or two thousand years before 1850, with regionally varying fluctuations such as the Medieval Warm Period and the Little Ice Age.
Global warming signs include sea level rise (water expands as it warms), widespread melting of snow and ice, increased heat content of the oceans, increased humidity, and the earlier timing of spring events etc.
Temperature changes vary over the globe. Since 1979, land temperatures have increased about twice as fast as ocean temperatures (0.25°C per decade against 0.13°C per decade). Ocean temperatures increase more slowly than land temperatures because of the larger effective heat capacity of the oceans and because the ocean loses more heat by evaporation.
3. Essay on the Essay on the Causes of Temperature Changes (Global Warming):
The following are some of the main causes of global warming:
(i) External Factors:
The climate system can respond to changes in external factors which can ‘push’ the climate in the direction of warming or cooling. These factors include changes in atmospheric composition (e.g., increased concentrations of greenhouse gases), solar luminosity, volcanic eruptions, and variations in Earth’s orbit around the Sun.
Orbital cycles vary slowly over tens of thousands of years and at present are in an overall cooling trend which would be expected to lead towards an ice age, but the 20th century instrumental temperature record shows a sudden rise in global temperatures.
(ii) Greenhouse Gases:
The greenhouse effect is the process by which absorption and emission of infrared radiation by gases in the atmosphere warm a planet’s lower atmosphere and surface. Naturally occurring amounts of greenhouse gases have a mean warming effect of about 33°C (59°F).
The major greenhouse gases are water vapour, which causes about 36-70% of the greenhouse effect; carbon dioxide (CO2), which causes 9-26%; methane (CH4), which causes 4-9%; and ozone (03), which causes 3-7%. Clouds also affect the radiation balance through cloud forcing similar to greenhouse gases.
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. The concentrations of CO2 and methane have increased by 36% and 148% respectively since 1750.
These levels are much higher than at any time during the last 800,000 years, the period for which reliable data has been extracted from ice cores. Fossil fuel burning has produced about three-quarters of the increase in CO2 from human activity over the past 20 years.
The rest of this increase is caused mostly by changes in land-use, particularly deforestation. Over the last three decades of the 20th century, gross domestic product per capita and population growth were the main drivers of increases in greenhouse gas emissions. CO2 emissions are continuing to rise due to the burning of fossil fuels and land-use change.
Emissions scenarios, estimates of changes in future emission levels of greenhouse gases, have been projected that depend upon uncertain economic, sociological, technological, and natural developments. In most scenarios, emissions continue to rise over the century, while in a few, emissions are reduced.
Fossil fuel reserves are abundant, and will not limit carbon emissions in the 21st century. Emission scenarios, combined with modelling of the carbon cycle, have been used to produce estimates of how atmospheric concentrations of greenhouse gases might change in the future.
The popular media and the public often confuse global warming with ozone depletion, i.e., the destruction of stratospheric ozone by chlorofluorocarbons. Although there are a few areas of linkage, the relationship between the two is not strong. Reduced stratospheric ozone has had a slight cooling influence on surface temperatures, while increased troposphere ozone has had a somewhat larger warming effect.
(iii) Particulates and Soot:
The effect of particulates and soot leads to a phenomenon called global dimming, which is a gradual reduction in the amount of global direct irradiance at the Earth’s surface. It was observed from 1961 until 1990. The main cause of this dimming is particulates produced by volcanoes and human made pollutants, which exerts a cooling effect by increasing the reflection of incoming sunlight.
The effects of the products of fossil fuel combustion – CO2 and aerosols – have largely offset one another in recent decades, so that net warming has been due to the increase in non-CO2 greenhouse gases such as methane.
Radiative forcing due to particulates is temporally limited due to wet deposition which causes them to have an atmospheric lifetime of one week. Carbon dioxide has a lifetime of a century or more, and as such, changes in particulate concentrations will only delay climate changes due to carbon dioxide.
Soot may cool or warm the surface, depending on whether it is airborne or deposited. Atmospheric soot directly absorbs solar radiation, which heats the atmosphere and cools the surface. In isolated areas with high soot production, such as rural India, as much as 50% of surface warming due to greenhouse gases may be masked by atmospheric brown clouds.
When deposited, especially on glaciers or on ice in arctic regions, the lower surface albedo can also directly heat the surface. The influences of particulates, including black carbon, are most pronounced in the tropics and sub-tropics, particularly in Asia, while the effects of greenhouse gases are dominant in the extra tropics and southern hemisphere.
(iv) Solar Activity:
Since 1978, output from the Sun has been precisely measured by satellites. These measurements indicate that the Sun’s output has not increased since 1978, so the warming during the past 30 years cannot be attributed to an increase in solar energy reaching the Earth.
In the three decades since 1978, the combination of solar and volcanic activity probably had a slight cooling influence on the climate. Climate models have been used to examine the role of the sun in recent climate change. Models are unable to reproduce the rapid warming observed in recent decades when they only take into account variations in solar output and volcanic activity.
Another line of evidence against the sun having caused recent climate change comes from looking at how temperatures at different levels in the Earth’s atmosphere have changed. Models and observations show that greenhouse warming results in warming of the lower atmosphere (called the troposphere) but cooling of the upper atmosphere (called the stratosphere).
Depletion of the ozone layer by chemical refrigerants has also resulted in a strong cooling effect in the stratosphere. If the sun was responsible for observed warming, warming of both the troposphere and stratosphere would be expected.
(v) Feedback:
The climate system includes a range of feedbacks which alter the response of the system to changes in external factors. There are a range of feedbacks in the climate system, including water vapour, changes in ice-albedo (snow and ice cover affect how much the Earth’s surface absorbs or reflects incoming sunlight), clouds, and changes in the Earth’s carbon cycle (e.g., the release of carbon from soil). Feedbacks are an important factor in determining the sensitivity of the climate system to increased atmospheric greenhouse gas concentrations.
4. Essay on the Effects of Global Warming:
Global warming effects can be detected and analysed by observing the changes in various natural effects. ‘Detection’ is the process of demonstrating that climate has changed in some defined statistical sense, without providing a reason for that change. Detection does not imply attribution of the detected change to a particular cause.
‘Attribution’ of causes of climate change is the process of establishing the most likely causes for the detected change with some defined level of confidence. Detection and attribution may also be applied to observed changes in physical, ecological and social systems.
Major effects of global warming are:
(i) Natural Systems:
Global warming has been detected in a number of natural systems. Some of these changes are receding of glaciers since the early 1800s. Other effects include sea level rise and widespread decreases in snow and ice extent. The melting of ice sheets could result in even higher sea level rise. Partial de glaciation of the Greenland ice sheet, and possibly the West Antarctic Ice Sheet, could contribute to sea level rise.
(ii) Ecological Systems:
In terrestrial ecosystems, the earlier timing of spring events, and pole-ward and upward shifts in plant and animal ranges, have been linked with high confidence to recent warming. Future climate change is expected to particularly affect certain ecosystems, including tundra, mangroves, and coral reefs. It is expected that most ecosystems will be affected by higher atmospheric CO2 levels, combined with higher global temperatures.
Overall, it is expected that climate change will result in the extinction of many species and reduced diversity of ecosystems. Dissolved CO2 increases ocean acidity. This process is known as ocean acidification. Increased ocean acidity decreases the amount of carbonate ions, which organisms at the base of the marine food chain, such as foraminifera, use to make structures they need to survive.
(iii) Effects on Social Systems:
Vulnerability of human societies to climate change mainly lies in the effects of extreme-weather events rather than gradual climate change. Impacts of climate change so far include adverse effects on small islands, adverse effects on indigenous populations in high-latitude areas, and small but discernable effects on human health.
Over the 21st century, climate change is likely to adversely affect hundreds of millions of people through increased coastal flooding, reductions in water supplies, increased malnutrition and increased health impacts.
(iv) Effect on Food Security:
With the fast growing population all over the world, global warming can affect the crop yield at many places and it will be difficult to meet the food demand of increased population in the future.
(v) Habitat Inundation:
In small islands and mega deltas across the world, inundation as a result of sea level rise is expected to threaten vital infrastructure and human settlements. This could lead to issues of statelessness for populations in many small island countries such as the Maldives and Tuvalu and homelessness in countries with low lying areas such as Bangladesh.
Reducing Global Warming Effects:
Climate Change Mitigation:
Reducing the amount of future climate change is called mitigation of climate change. The IPCC defines mitigation as activities that reduce greenhouse gas (GHG) emissions, or enhance the capacity of carbon sinks to absorb GHGs from the atmosphere.
Studies indicate substantial potential for future reductions in emissions by a combination of emission-reducing activities such as energy conservation, increased energy efficiency, and satisfying more of society’s power demands with renewable energy and/or nuclear energy sources. Climate mitigation also includes acts to enhance natural sinks, such as reforestation.
In order to limit warming to within the limit, it will be necessary to adopt policies that will limit greenhouse gas emissions to one of several significantly different scenarios described in the full report. This will become more and more difficult with each year of increasing volumes of emissions and even more drastic measures will be required in later years to stabilize a desired atmospheric concentration of greenhouse gases.
5. Essay on Global Warming and Solar Radiation:
Recently the UN scientific team has warned that massive flooding; disease and drought could hit rich and poor countries around the world over coming decades if global warming is not halted. “Projected climate changes during the 21st century have the potential to lead to future large-scale and possibly irreversible changes in Earth systems, resulting in impacts on continental and global scales” the report said.
The scientists said they foresaw glaciers and polar icecaps melting, countless species of animals, birds and plant life dying out, farmland turning to desert, fish supporting coral reef destroyed and small island states sunk beneath the sea. However, many other scientists do not believe in such bleak future of the earth. These scientists have just reverse opinion on the sources and impacts of global warming and greenhouse effects.
According to Accu-Weather, the world’s leading commercial forecaster, “Global air temperatures as measured by land-based stations show an increase of about 0.45°C over the past century. This may be no more than normal climatic variations.”
On the contrary, satellite data indicate a slight cooling in the climate in the last 18 years. These satellites use advanced technology and are not subject to the “heat island” effect around major cities that alters ground-based thermometers.
Many scientists point out that during the past 150 years the earth’s temperature has gone up by 1.5°F due to ever increasing greenhouse gases in the atmosphere. Other scientists point out that of the 1.5°F, two-thirds of that increase, or 1°, occurred between 1850 and 1940.
In the last 50 years, the planetary temperature increased at a significantly slower rate of 0.5°F—precisely when dramatically increasing amounts of man-made carbon dioxide emissions should have been accelerated warming. Further buttressing the arguments for future cooling is the evidence from NASA satellites that the global temperature has actually fell 0.04°F since 1979.
Many scientists are of the opinion that those looking for the culprit responsible for global warming have missed the obvious choice—the sun. While it may come as a newsflash to some, scientific evidence conclusively shows that the sun plays a far more important role in causing global warming and global cooling than any other factor, natural or man-made. Atmospheric circulation, the cause of weather, is driven by the sun’s energy.
Climate is the integral of weather over periods of more than a year. This integral also depends on the flux of solar energy. There is a strong correlation between the variations in solar irradiant and fluctuations in the earth’s temperature. When the sun gets dimmer, the earth gets cooler; when the sun gets brighter, the earth gets hotter. So important is the sun in climate change that half of the 1.5°F temperature increases since 1850 is directly attributable to changes in the sun.
According to NASA scientists David Lind and Judith Lean, only one-quarter of a degree can be ascribed to other causes, such as greenhouse gases, through which human activities can theoretically exert some influence. Many scientists are of the view that as much as 98% of total greenhouse gas emissions are natural (mostly water vapours) and only 2% are from man-made sources.
By most accounts, man-made emissions have had no more than a minuscule impact on the climate. A Gallup survey indicated that only 17% of the members of the American Meteorological Society and the American Geophysical Society thought the warming of the 20th century was the result of an increase in greenhouse gas emissions.
Solar radiation is driven mainly by two types of cycles. The correlation between major changes in the earth’s temperature and changes in solar radiance is quite compelling. A perfect example is the Little Ice Age that lasted from 1650 to 1850. Temperatures in this era fell to as much as 2°F below today’s temperature. Interestingly, this dramatic cooling happened in a period when the sun’s radiance had fallen to exceptionally low levels.
Between 1645 and 1715, the sun was in a stage that scientists refer to as the Maunder Minimum. In this minimum, the sun has few sunspots and low magnetism, which automatically indicates a lower radiance level. When the sun began to emerge from the minimum, radiance increased and by 1850 the temperature had warmed up enough for the Little Ice Age to end.
The Maunder Minimum is not an isolated event; it is a cyclical phenomenon that typically appears for 70 years following 200-300 years of warming. With only a few exceptions, whenever there is solar minimum the earth gets colder. For example, Europe in the 13th and 15th Centuries experienced significantly lower temperatures and in both cases the cold spells coincides with a minimum.
Similar correlation was found in the 9th Century and again in 7th Century. Since 8700 B.C., there have been at least ten major cold periods similar to the Little Ice Age, and nine of these cold spells coincided with Maunder Minima. Dr. Sallie Baliunas, an astrophysicist with the Harvard-Smithsonian Centre for Astrophysics, believes that we may be nearing the end of a solar warming cycle.
Since the last minimum ended in 1715, Baliunas says there is a strong possibility that the earth will start cooling off in the early part of the 21st Century. Dr. Theodor Landscheidt of the Schroeter Institute for Research in Cycles of Solar Activity, Canada, forecasted as early as in 1982, that we should expect declining temperatures after 1990 and probably a new Little Ice Age around 2030. He also predicted considerably weaker sunspot activity after 1990. The slowly ascending new sunspot cycle, which started in May 1996, seems to follow the predicted trend.
Changes of solar irradiant have been directly observed since 1978 and are mainly linked to the variability of magnetic activity, which is manifested by the number of sunspots. The amplitude of the irradiant variations is approximately 0.1 percent over the 11-year cycle. This variation may appear insignificant, but its indirect influence on climate is great. Variability in the ultraviolet radiation affect the ozone in upper atmosphere and thus may lead to temperature change.
Solar variability also modulates the cosmic rays, which in turn may affect the cloud cover and thus also leads to a temperature change. Clouds have a hundred times stronger effect on weather and climate than carbon dioxide in the atmosphere. Even if the atmosphere’s carbon dioxide content doubled, its effect would be cancelled out if the cloud cover expanded by 1 percent. These indirect effects are highly nonlinear and therefore may well be larger than the direct effect.
Changes in the ultraviolet radiation of the sun are much greater than in the range of visible radiation. The ultraviolet range of the spectrum lies between 100 Å and 3800 Å. Wavelengths below 1500 Å are called extreme ultraviolet (EUV). The variation in radiation between extreme of the 11 -year sunspot cycle reaches 35 percent in the EUV-range, 20 percent at 1500 Å and 7 percent around 2500 Å.
At wavelengths above 2500 Å, the variation reaches still 2 percent. At the time of energetic solar eruptions, the UV radiation increases by 16 percent. At a sunspot maximum the EUV radiation raises the temperature in the ionosphere by 300 percent in relation to minimum, but most important factor is that the UV radiation below 2900 Å is completely absorbed by ozone in the stratosphere. The resultant rise in temperature is augmented by positive feedback, as the UV radiation also generates new ozone. Satellite observations show that the ozone content grows by 2 percent from sunspot minimum to maximum.
At the time of current sunspot cycle, levels of solar radiation appear not to have reached those seen in the two previous cycles, said Judith Lean of the Naval Research Laboratory in Washington, D.C. The consensus drawn from long-term observations in space and independent calculations is that the increase will likely be about 30 percent less during the present activity cycle than during the peaks of two prior cycles.
Before the current sunspot cycle started, the previous two cycles occurred during the periods 1974-1985 and 1985-1996. Those two cycles turned out to have two of the three highest peaks of activity ever recorded. The reduction in peak solar radiation levels is consistent with a peak in sunspot activity that also is expected to be lower than the last two cycles.
It is certain that much more study is required on the subject of global warming and greenhouse effects. While supporters of global warming cite the examples, such as 1997 and 1998 have consequently been the warmest years on record, 1990s was the warmest decade and 1900s was the warmest century during the last 1,000 years, the opponents simply ignore the greenhouse gases emissions.
Its possible impacts are seen as more hurricanes and drought, climate change, irregular precipitation, large scale melting of polar ice caps and rise in sea levels, but other scientists see the arrival of Ice age. Yet, there is a point of general agreement—greenhouse effect.
All scientists believe in the greenhouse effect, and without it the planet would be largely frozen. It is because of this greenhouse like function of the atmosphere that the average global temperature of the earth is 15°C. Without the atmosphere and these gases, the average global temperature would be a frigid—18°C, and life would not be possible on earth.
6. Essay on Global Warming and Malnutrition:
Agriculturally, many scientists believe that global warming is good for human race, because it helps increase food production. The most determinant factor in agricultural production is climate. History reveals that for food production warming is better than cooling. Carbon dioxide is an essential nutrient for production of food and food is one of the most important things in our lives.
As the temperature increases, more farmland will be open towards the poles and the length of the growing season will also lengthen. Many recent studies indicate that agricultural productivity will increase in most parts of the USA. In India too, the States of West Bengal, Orissa and Andhra Pradesh are predicted to benefit to a small extent from warming.
About three decades ago, Dr. R.W.F. Hardy and his team at E.I. du Pont de Nemours and Company have experimented with soybean plants under different CO2 concentrations to see if increases in photosynthesis also lead to increase in nitrogen in the seeds. Their results show that doubling the CO2 concentration lead to a slight increase in the total weight of the plant body and the number and weight of seeds.
Carbon Dioxide (CO2) is a colorless, odorless, non-flammable gas and is believed to be the most prominent Greenhouse gas in Earth’s atmosphere. It is recycled through the atmosphere by the process photosynthesis, which makes human life possible. Photosynthesis is the process of green plants and other organisms transforming light energy into chemical energy.
Light Energy is trapped and used to convert carbon dioxide, water, and other minerals into oxygen and energy rich organic compounds. Carbon Dioxide is emitted into the air as humans exhale, burn fossil fuels for energy, and deforests the planet. Every year humans add over 30 billion tonnes of carbon dioxide in the atmosphere by these processes, and it is up thirty percent since 1750.
An isolated test at Mauna Loa in Hawaii revealed more than a 12% (316 ppm in 1959 to 360 ppm in 1996) increase in mean annual concentration of carbon dioxide. Mauna Loa, located in Hawaii, is the largest volcano at 40,000 cubic km and 4,170 meters above sea level. Ice core samples have also shown a dramatic increase in carbon dioxide levels.
Drilling deep into glaciers and polar ice caps and taking out samples of ice, then melting the ice and capturing the gas has shown an increase in carbon dioxide concentrations over the past 100 years. Ice core samples are essentially “drilling through time,” because the deeper the ice is, the older the ice is.
Fossil Fuels were created chiefly by the decay of plants from millions of years ago. We use coal, oil and natural gas to generate electricity, heat our homes, power our factories and run our cars. These fossil fuels contain carbon, and when they are burned, they combine with oxygen, forming carbon dioxide. The two atoms of oxygen add to the total weight.
Deforestation is another main producer of carbon dioxide. The causes of deforestation are logging for lumber, pulpwood, and fuel wood. Also contributing to deforestation is clearing new land for farming and pastures used for animals such as cows. Forests and wooded areas are natural carbon sinks. This means that as trees absorb carbon dioxide, and release oxygen, carbon is being put into trees. This process occurs naturally by photosynthesis, which occurs less and less as we cut and burn down trees.
As the abundance of trees declines, less carbon dioxide can be recycled. As we burn them down, carbon is released into the air and the carbon bonds with oxygen to form carbon dioxide, adding to the greenhouse effect. About 860 acres of forestland, is destroyed every 15 minutes in the tropics.
A new study also suggests that crop productivity will increase with carbon dioxide increase, but warns that nutritional quality of some crops will decrease under such circumstances. Under high CO2 concentrations the plants produce more seeds with less nitrogen content.
Nitrogen is a critical component for building proteins in plants, humans and animals. Many scientists believe that under the rising CO2 scenario, livestock and humans would have to increase intake of plants to compensate for the loss of nitrogen.
The proteins are made up of amino acids, which are composed of carbon, hydrogen, oxygen, nitrogen and sometimes sulphur. Proteins play many important roles, as enzymes, as structural components of the cells and as regulators of a variety of body functions. On a global scale, plants directly provide 88 percent of the calories and 80 percent of the protein that human beings consume; the rest comes from animal products.
This study has been conducted by a team of experts led by Peter Curtis, Professor of evolution, ecology and organismal biology at Ohio State University. The researchers analyzed eight different ways plants respond to higher CO2 levels—number of flowers, number of fruits, fruit weight, number of seeds, total seed weight, individual seed weight, amount of nitrogen in seeds and plants capacity to reproduce.
The team found that the plants grown at higher CO2 levels had more flowers, more seeds, greater individual seed weight, greater total seed weight but lower concentration of nitrogen in the seeds.
Individual crops varied in their response to increased CO2 levels. Rice seemed to be most responsive and its seed production increased by 42 percent. Soybeans followed with a 20 percent increase in seeds, wheat by 15 percent and corn increased by 5 percent. Nitrogen level decreased by an average of 14 percent across all plants except cultivated legumes.
The concentrations of carbon dioxide within the leaf, and the affinity of the photosynthetic enzymes for CO2, are important variables that affect the rate of photosynthesis in plants. The concentration of CO2 in the leaf is limited by the concentration of this gas in the atmosphere and by its diffusion through the stomates into the leaf cells.
At high light intensities, increase in CO2 concentration up to 01 percent (normal CO2 concentration in air is about 0.03%), increases the rate of photosynthesis because CO2 can enter the leaf more rapidly. Higher concentrations of CO2 (beyond 1%) are definitely poisonous to plants.
Peter Curtis concludes the report as “that’s bad news. Nitrogen is important for building proteins. A growing global population demands more food, but humans would have to eat more of the food to get the same nutritional benefits.”
7. Essay on the Politics of Global Warming:
“It is not in Australia’s interest to ratify the Kyoto Protocol,” said Australian Prime Minister John Howard while celebrating the World Environment Day this year. The reasons cited by him were that the protocol would cost jobs and damage the industry.
Under the Kyoto Protocol, an addition to the United Nations Framework Convention on Climate Change, 37 industrialized nations have agreed to cut their emissions of six greenhouse gases linked to global warming. Thirty- nine nations were to have been governed by the original agreement signed in Kyoto, Japan in December 1997, but the Bush administration said that the United States would not ratify, and now Australia, too, has backed away from the agreement.
Recently a report brought out by the US Environmental Protection Agency (EPA) clearly states that “Greenhouse gases are accumulating in earth’s atmosphere as a result of human activities, causing global mean surface air temperature on rise.”
Just next day after the release of the report, President Bush rejected it and called it a “product of bureaucracy.” “I do not support the Kyoto Treaty, it would severely damage the United States economy” Bush said, reiterating the position he has held since his election.
The EPA report, Climate Action 2002, warns that total US greenhouse gas emissions are expected to increase by 43 percent between 2000 and 2020, despite Bush administration programs to encourage voluntary reductions in greenhouse gas emissions and the use of technology to store or sequester excess carbon dioxide. The United States is the world’s largest emitter of carbon dioxide, the major heat trapping gas released by burning fossil fuels and the main cause of global warming.
The countries that ratify the agreement must reduce emissions of carbon dioxide to an average of 5.2% below 1990 levels during the five-year period 2008 to 2012. Countries of the European Union, which ratified the protocol recently, agreed to cut their emissions by eight percent. Australia had secured the right to increase its emissions to a limit of eight percent by 2012, but even that target is not generous enough for the Howard Government to support ratification.
In the beginning of June 2002, Japan ratified the Kyoto Protocol, following close on the heels of 15 members of the European Union. Russia has said it will ratify the pact as soon as possible. For the protocol to become legally binding, it must be ratified by at least 55 countries and by industrialized nations that emitted at least 55% of the world’s CO2 in 1990. If Russia ratifies the protocol, it could take effect before the end of the year.
Kyoto Protocol is completely based on the assumption that the earth is warming up and climate is changing. But many scientific studies indicate that the science, reason and impact of global warming are still not clear.
New Facts on Global Warming Reveal that:
i. The surface temperature of the earth has gone up about 0.7°C in the last 100 years, but one-half of that occurred before human influence could have contributed much, and about one- tenth of the more recent warming was also contributed by solar changes, as noted by Judith Lean and David Rind in the Journal of Climate. That leaves a grand total of about 0.3°C from humans.
ii. The majority of warming in recent decades is in winter.
iii. The U.N. made 245 separate climate forecasts for this century. The Intergovernmental Panel on Climate Change (IPCC) concludes that the earth’s average temperature can be expected to rise between 2.5 and 10.4°F this century. It was based upon a totally outlandish assumption about the amount of energy used per capita.
This assumption has not been true since carbon dioxide measurement was started. This amount of warming would require unprecedentedly large changes in per capita energy use. NASA’s James Hansen estimates that the likely warming for the next half-century is only about three- quarters of a degree Celsius.
iv. Many recent studies have demonstrated that the large glaciers in Antarctica are growing, not shrinking, and overall temperature of the region is going down.
v. The IPCC has stated that in last 40 years, the global average sea level has risen ocean heat content has increased and snow cover and ice extent has decreased. But IPCC also notes that there has been no acceleration in the rate of sea level rise in the last century. The satellite data show that the UN estimates of sea-level rise are generally too high and that the rise from the warming in the last 100 years is likely to be a mere 2.5 inches, compared with commonly cited 6 inches.
Scientists also found no net change in Greenland ice, the second largest ice field in the world. The change in oceanic heat content largely occurred in a temperature jump in 1976 known as the “great pacific climate shift,” a phenomenon with no known scientific link to greenhouse gas changes.
vi. Countless scientific studies demonstrate that an increased greenhouse effect would greatly increase crop yields worldwide. Sanitation improvements, possible with economic development, are far more effective at quelling the spread of tropical diseases than attempting to control local climate.
Industrialized countries always try to push their environmental standards and guidelines in developing countries. They even put environment on business agenda. But, they fail to appreciate a fundamental truth, richer nations including the US have the resources to avoid or clean up environmental pollution.
Poorer nations such as China or Ghana or even India, which must devote a much larger portion of their resources just to subsistence, do not have that luxury. Imposing expensive environmental mandates like the Kyoto Treaty on industries will only make us poorer, and reduce our ability to control pollution.
When the environmental status of China and the US is compared, China’s environment seems to be more degraded. China is considered a wasteland of pollution as images from space taken by NASA show the eastern part of the country choked in brown smog. While Beijing— where coughing is routine—had completely disappeared under the haze. China produces twice the carbon dioxide as America does.
The US has an $8.9 trillion economy with the population or roughly 285 million people, while China’s economy is only one-ninth of the US spread over about 4.5 times as many people. In the US air particulate declined 65 percent from 1970 to 1998, toxic release fell by nearly half between 1988 and 1998, and since 1980 most of the air pollutants have decreased. While the US economy in 1999 was more than 30 percent larger than it was in 1991, carbon dioxide emissions per Dollar of Gross Domestic Product (GDP) were about 85% of their 1991 level.
For the past two decades, global warming is seen as biggest threat to our environment. Almost every month international conferences are being organized on the topic, but concrete evidence about man-made warming is still lacking.
Richer countries, like Australia and the USA, find it difficult economically to follow the Kyoto Protocol but at the same time want India and China should cut their carbon dioxide emissions. It seems that the whole issue has acquired a political dimension, and developed countries are pressurizing to developing countries for an unproven subject.
8. Essay on You Can Also Reduce Global Warming:
If only one-third of the US population would simply tweak a few daily habits, enough carbon dioxide would be saved to achieve the United States’ original emission reduction target under the Kyoto Protocol, according to the authors of a new book, You Can Prevent Global Warming- 51 Easy Ways. What is more, according to the book, each household that makes the effort could save as much as US $2000 each year.
This book is written by Jeffrey Langholz, environmental policy expert at Monterey Institute of International Studies, California and Kelly Turner, an environmental writer based in New York City. Through this book the authors have also tried to prove that economic growth and environmental protection can go hand in hand.
This issue is important because in March 2001, the United States formally withdrew support for the international global warming treaty, called the Kyoto Protocol. One of the major concerns cited was that reduction of gas emissions could hurt the economy.
You Can Prevent Global Warming focus entirely on conserving energy, reducing the demand for fossil fuels by becoming more careful and efficient in everyday usage of electricity, heating and gasoline. Reduced burning of fossil fuels will cut the greenhouse gases released into the atmosphere, especially in the form of carbon dioxide.
According to the book, making a contribution to reducing the use of fossil fuels can be as simple as changing a light bulb. As compared to traditional bulbs, the compact fluorescent lamps last ten times longer, use one-fourth of the energy and produce more light per watt.
Although the purchase price of compact fluorescent lamps initially cost more than incandescent ones, they quickly pay for themselves and start saving consumers money thanks to their long life and lower energy consumption. The authors conclude that if every household in the United States replaces its next fused light bulb with a compact fluorescent lamp, more than 13 billion pounds of carbon dioxide can be prevented escaping into the atmosphere.
There are many ways to reduce the energy consumption of the household refrigerators. Dialing up the appliance’s temperature by 1 degree, placing the fridge in a cool spot, checking that the seals work properly and keeping the doors closed, are just some of the tips. Simply dusting off the condenser coils at the back of the fridge twice a year would make it more efficient.
Letting the sink run while you brush your teeth or shave wastes water and energy. Just one leaky joint that drips every three seconds can waste 110 litres of water a month. An 8-minute shower compared with a 10-minute shower will save about 1,100 litres of water a month. Installing low-flow showerheads can save much more water.
The appliances that are switched off consume at least 5 percent of the annual electricity bill, according to the authors. One-fourth of the’ electricity consumed each year by the TV is used when it is turned off. Most of the people are ignorant about this leaking effect. Any appliance or piece of electronic or office equipment that has a remote control, battery charger, internal memory, AC adapter plug, instant-on feature, permanent display, or sensor will use electricity even when it is switched off.
The only way to stop wasting that energy is to unplug them. The annual amount of money saved as a result of enabling the sleep feature on your computer, monitor and printer to go on after 5 minutes of inactivity is US $22, the authors have calculated.
Improving the fuel efficiency of your car is the single best thing you can do to prevent global warming. You can also make a difference by choosing what kind of car you drive, how often you drive and how you drive it. A tune-up could improve the car’s efficiency by 15 to 50 percent. The more smoothly you drive the less gasoline the car will use. Accelerating or braking rapidly can worsen the fuel efficiency by 33 percent. Keeping the tires properly inflated can reduce the gasoline consumption by 6 percent.
The book suggests several other ways to reduce the emission of greenhouse gases. For example, an American eats 120 kilograms of beef per year. By eating half a kilogram less per week a substantial amount can be saved. The electricity needed to water, feed, slaughter, and package just half a kilogram of beef is equivalent of burning 3.8 litres of gasoline in your car’s engine.
We can follow following easy steps to reduce global warming:
i. Avoid wastage of electricity and water;
ii. Turn off the light when it is not required;
iii. Maximum use of solar light;
iv. Use air-conditioners only when it is really required;
v. If sunlight is available in plenty, avoid using dryers of washing machine;
vi. Use your car judiciously;
vii. Do not burn the garbage.
Never consider your contribution too small, only the small contributions when joined together make appreciable impact.