CLIMATE CHANGE AND GLOBAL WARMINGshodhganga.inflibnet.ac.in/bitstream/10603/37821/11/11...Climate...
Transcript of CLIMATE CHANGE AND GLOBAL WARMINGshodhganga.inflibnet.ac.in/bitstream/10603/37821/11/11...Climate...
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CHAPTER 2
CLIMATE CHANGE AND GLOBAL WARMING
‘Environment’1 refers to the sum total of condition, which surrounds point in
space and time. The scope of the term ‘Environment’ has been changing and widening
with the passage of time. In the primitive age2, the environment consisted of only
physical aspects of the earth’s land, air and water as biological communities. As the
time passed on, human beings extended the environment through their social,
economic and political activities. Now a day’s environmental issues are growing in
size and complexity, threatening the survival of mankind on earth. The key
environmental concerns today are climate change3, global warming, natural disasters,
and soil and land degradation, loss of biodiversity4, air and water pollution which
disturbs the balance of the living environment in a big way.5
‘Climate change’ refers to a statistically significant variation in either the
mean state of the climate6 or in its variability, persisting for an extended period
(typically, decades or longer). Climate change may be due to natural internal
processes or due to persistent anthropogenic7 activities that brings change in the
1 The natural environment encompasses all living and non-living things occurring naturally on Earth or some region thereof. It is an environment that encompasses the interaction of all living species. 2 The Primitive Age is the starting age for your civilization. The Stone Age is a broad prehistoric period during which stone was widely used to make implements with a sharp edge, a point, or a percussion surface. The period lasted roughly 3.4 million years, and ended between 6000 BCE and 2000 BCE with the advent of metalworking. Stone Age artifacts include tools used by humans and by their predecessor species in the genus Homo. 3 Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. Certain human activities have also been identified as significant causes of recent climate change, often referred to as “global warming.” The term sometimes is used to refer specifically to climate change caused by human activity, as opposed to changes in climate that may have resulted as part of Earth's natural processes. The most general definition of climate change is a change in the statistical properties of the climate system when considered over long periods of time, regardless of cause. Accordingly, fluctuations over periods shorter than a few decades, such as El Nino, do not represent climate change. 4 Biodiversity refers to the variety of life and its processes. It includes the variety of living organisms, the genetic differences among them, the communities and ecosystems in which they occur, and the ecological and evolutionary processes that keep them functioning, yet ever changing and adapting. 5 Santosh Kumar, “Environment and development ” Yojana, May 2012, p.14 6 The term Climate is originated from Ancient Greek term klima, meaning inclination. Climate is commonly defined as the weather averaged over a long period of time. The standard averaging period is 30 years, but other periods may be used depending on the purpose. Climate also includes statistics other than the average, such as the magnitudes of day-to-day or year-to-year variations.[Glossary of Metrology- American Metrological Society.] 7 The term anthropogenic designates an effect or object resulting from human activity. The term is sometimes used in the context of pollution emissions that are produced as a result of human activities but applies broadly to all major human impacts on the environment.
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composition of the atmosphere8. Earth is warming at an unusual rate and evidence of
warming is present in different forms.9
Climate change is perhaps the most serious environmental challenge humanity
has ever faced. While the extent of climate change and its environmental and
economic impacts are subject to debate, it is, nevertheless, clear that humans are
altering the earth’s climate in profound ways through burning fossil fuels 10 that
produce carbon dioxide, a heat-trapping gas, and from activities such as cutting of
forests and agriculture that produces methane, another greenhouse gas (GHG).
2.1 The Climate
Climate is the sum total of the Weather11 experienced at a place in the course
of a year and over the years. It comprises not only those conditions that can obviously
be described as ‘near average’ or ‘normal’ but also the extremes and all the
variations. 12 At the simplest level, the weather is what is happening to the
atmosphere13 at any given time while climate is what would be expected to occur at
any given time of the year based on statistics built up over many years. The frequently
changing extreme weather events14 exert a major influence on the interpretation of
changes in the climate; however, there may be some blurring of the distinction
between weather and climate in considering specific events.
It follows from the definition of weather and climate; that changes in the
climate constitute shifts in meteorological conditions lasting a few years or longer. 8The gaseous envelope surrounding the Earth. The dry atmosphere consists almost entirely of nitrogen (78.1% volume mixing ratio) and oxygen (20.9% volume mixing ratio), together with a number of trace gases, such as argon (0.93% volume mixing ratio), helium and radiatively active greenhouse gases such as carbon dioxide (0.035% volume mixing ratio) and ozone. In addition, the atmosphere contains the greenhouse gas water vapour, whose amounts are highly variable but typically around 1% volume mixing ratio. The atmosphere also contains clouds and aerosols. 9 Dr. Deoki Nandan, Vinod Joon, Vaishali Jaiswal, “Global Warming and the Challenges posed by Climate Change”, World Focus, September 2009, p. 362 10 Fossil fuels are fuels formed by natural processes such as anaerobic decomposition of buried dead organisms. The age of the organisms and their resulting fossil fuels is typically millions of years, and sometimes exceeds 650 million years. 11 Weather is taken to mean the totality of atmospheric conditions at: any particular place and time - the instantaneous state of the atmosphere and especially those elements of it which directly affect living things. Its meaning may be extended to include exposure to radiation from the sun and to the sky, as permitted by the state of the atmosphere. 12 H. H. Lamb, Climate: Present, Past & Future, Vol. 1, London: Methuen & Co. Ltd., 1972, p. 7. 13 An atmosphere is a layer of gases surrounding a planet or other material body of sufficient mass that is held in place by the gravity of the body. 14 Extreme weather includes unusual, severe or unseasonal weather; weather at the extremes of the historical distribution—the range that has been seen in the past. The most commonly used definition of extreme weather is based on an event’s climatological distribution: Extreme weather occurs only 5% or less of the time. According to climate scientists and meteorological researchers, extreme weather events have been rare. Some extreme weather events have been attributed to human-induced global warming, with a 2012 studies indicating an increasing threat from extreme weather.
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Those changes may involve a single parameter, such as temperature or rainfall but
usually accompany more general shifts in weather patterns which might result in a
shift to stay colder; whether, cloudier and windier conditions. Because of the
connection with global weather patterns these changes can result in compensating
shifts in different parts of the world. More often they are, however, part of an overall
warming or cooling of the global climate. But in terms of considering the implications
of changes in the climate, it is the regional variations which provide the most
interesting material as long as they are properly set in the context of global change.
The climate of a locality is defined by long-term statistics of the variables of
the state of the atmosphere at that locality. There are local and regional climates and
planetary or global climate. The regions chosen are generally the natural geographical
regions of the earth’s surfaces. Short time variations of meteorological parameters
entail “weather changes” while their long term variations entail “climate changes”.
The climate may be considered as the sum of a set of weather types, each of these
types having a characteristic frequency distribution over the averaging period.15
The behavior of the Earth’s climate is governed by a wide range of factors all
of which are interlinked in an intricate web of physical processes. Thus there is need
to define the meaning of climate change because various factors assume different
significance depending on the timescale under consideration.16 On the broadest scale,
the rate at which energy is received from the sun and the rate at which it is lost to
space determine the equilibrium temperature and climate of Earth. This energy is
distributed around the globe by winds, ocean currents, and other mechanisms to affect
the climates of different regions.
The climate has always been changing. On every timescale, since the Earth
was first formed its surface conditions have fluctuated. Past changes are etched on the
landscape, have influenced the evolution of all life forms and are a subtext of our
economic and social history. Current changes are a central part of the debate about the
consequences of human activities on the global environment, while the future course
of the climate could exert powerful constraints on economic development, especially
in developing countries.
The carbon dioxide in the atmosphere has increased by 31% since pre-
15 Inadvertent Climate Modification, Report of the Study of Man’s Impact on Climate, Sponsored by Mass Achnetts Institute of Technology, Cambridge, England: The MIT Press, 1971. 16 William James Burroughs, Climate Change- A Multidisciplinary Approach, Cambridge UK: Cambridge University Press, 2001, pp. 1-2.
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industrial times, causing more heat to be trapped in the lower atmosphere. There is
evidence to show that - carbon dioxide levels are still increasing. Human activities
during the last few decades of industrialization and population growth have polluted
the atmosphere to the extent that it has begun to seriously affect the climate.17
Factors that can shape climate are called climate forcings or “forcing
mechanisms.” These include processes such as variations in solar radiation, variations
in the Earth’s orbit, mountain-building and continental drift and changes in
greenhouse gas concentrations. Forcing mechanisms can be either “internal” or
“external”. Internal forcing mechanisms are natural processes within the climate
system itself (e.g., the thermohaline circulation18). External forcing mechanisms can
be either natural (e.g., changes in solar output) or anthropogenic (e.g., increased
emissions of greenhouse gases).19
2.1.1 Natural process of Climate Change
The climate of the earth has never been stable, least of all during the history
and evolution of the human species. Glacial periods20, globally have been 4-5°C
cooler than now, and some interglacial have perhaps been 1-2°C warmer. Changes in
climate were clearly natural in origin (i.e. not related to human behavior) occurring on
a planet inhabited by primitive societies with far smaller populations than at present.
The causes are now dominated by human perturbation of the atmosphere. The
rate of warming already exceeds anything experienced in the last 10000 years and is
set to be more rapid than anything experienced in human history. And the significance
for humanity is qualitatively different from the previously given ecological imprint
made by the current and growing, population of 6 billion and more.21
17 Environmental Studies for Undergraduate Courses, Hyderabad: Universities Press Pvt. Ltd., pp. 177-178. 18 Large-scale circulation in the ocean that transforms low-density upper ocean waters to higher-density intermediate and deep waters and returns those waters back to the upper ocean. The circulation is asymmetric, with conversion to dense waters in restricted regions at high latitudes and the return to the surface involving slow upwelling and diffusive processes over much larger geographic regions. The THC is driven by high densities at or near the surface, caused by cold temperatures and/or high salinities, but despite its suggestive though common name, is also driven by mechanical forces such as wind and tides. 19 http://en.wikipedia.org/wiki/Climate_change#Precipitation accessed on 11th Feb. 2013 20 A glacial period (or alternatively glacial or glaciations) is an interval of time (thousands of years) within an ice age that is marked by colder temperatures and glacier advances. Interglacials, on the other hand, are periods of warmer climate between glacial periods. The last glacial period ended about 15,000 years ago; [1] The Holocene epoch is the current interglacial. 21 Mike Hulme, A Change in the Weather? Coming to Terms with Climate Change, France Harris, Global Environmental Issue, England: John Wiley & Sons Ltd., 2004, p. 21.
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For most of Earth’s history, the planet has been either very cold, by our
standards, or very hot. Fifty million years ago there was no ice on the poles. Over the
last two million years the dominant pattern was the Pleistocene glacial/interglacial
cycle22, with a period of around 100000 years. Global average temperatures varied by
5-7°C between glacial and interglacial and average temperature in some middle and
high latitude regions in the Northern Hemisphere varied by 10 - 15°C. The reason for
the glacial-interglacial cycle23 is believed to be small changes in summer radiation
receipts, caused by periodic variations in the earth’s orbit. The earth emerged from the
latest glacial period between 10000 and 15000 years ago: during the period (since
then the Holocene) there have been a number of significant events.24
Eighteen thousand years ago there was ice two miles thick in Scotland and,
because of the size of the ice sheets; the sea level was 130 m lower. Ice-core studies
show that in some places dramatic changes happened remarkably swiftly;
temperatures rose by as much as 20° C in a decade. Then, 10,000 years ago, the wild
fluctuations stopped, and the climate settled down to the balmy, stable state that the
world has enjoyed since then. At about that time, perhaps coincidentally, perhaps not,
mankind started to progress.25
Global climate varies naturally due to both ‘internal variability’ within the
climate system changes in ‘external forcing’ unrelated to human behavior, for
example, changes in solar irradiance and volcanic activity. The reconstruction of
temperature over the past thousand years suggests, however, that the warming over
the 20th century is unusual and unlikely to be merely the response of the system to
natural forcing.
The world has warmed since 1860, when the instrumental record started.
Warming has continued into the 21st century, and the year 2002 is second only to 22 The glacial period that peaked 21,500 years ago was only the most recent of five glacial periods in the last 450,000 years. In fact, the Earth system has alternated between glacial and interglacial regimes for more than two million years, a period of time known as the Pleistocene. The duration and severity of the glacial periods increased during this period, with a particularly sharp change occurring between 900,000 and 600,000 years ago. Earth is currently within the most recent interglacial period, which started 11,700 years ago and is commonly known as the Holocene Epoch. 23 Large, continental ice-sheets in the Northern Hemisphere have grown and retreated many times in the past. Times with large ice-sheets are known as glacial periods (or ice ages) and times without large ice-sheets are interglacial periods. The most recent glacial period occurred between about 120,000 and 11,500 years ago. Since then, the Earth has been in an interglacial period called the Holocene. Glacial periods are colder, dustier and generally drier than interglacial periods. These glacial-interglacial cycles are apparent in many marine and terrestrial paleoclimate records from around the world. 24 Nigel Arnell, Global Warming River flows and Water resources, West Sussex, England: John Wiley & Sons, , 1996, p.7. 25 “The Heat is On: A special Report on Climate Change”, The Economist, Sept. 9, 2006, p. 9.
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1998 for observed global warming, the 1990 is likely to have been the warmest
decade in the past 1000 years. According to UN meteorologists, year 2012 has ranked
among the nine warmest since records began more than 160 years ago, continuing a
trend for the planet that is increasing the dangers of extreme weather events.
A warming of global climate, of what so ever magnitude will inevitably alter
the characteristics of weather experienced in all regions and localities. The climate
system is fully integrated and warming it by 1°C or more will alter for example; the
distribution of magnitude of precipitation over the earth’s surface, the frequency,
severity and distribution of storms around the world, and the nature of thermal
regimes, especially extreme heat and extreme cold. Human modification of the global
climate will also induce changes in the behavior of natural, large-scale oscillatory
phenomena in the climate system.26
The exchange of carbon between the atmosphere and the biosphere27 is a
major factor in the climate system. The natural exchange, which has been going on for
hundreds of millions of years, is becoming increasingly altered due to human
activities via land use, changes in land use, and forestry. A good description of all
these processes is essential in the understanding of the causes of anthropogenic
climate change.28
2.1.2 Anthropogenic Climate Change
All animals including the Homo sapiens are dependent upon the environment,
particularly the physical environment, i.e., nature. It is well known that the earth’s
surface and the environment surrounding it are important to human health. The
relationship between human health and his environment is a two-way process. We
improve our living conditions and increase our comforts but the alterations to the
environment may be harmful to our health. The nature of the soil, air, water,
temperature, barometric pressure, wind, sunshine, cloud, rainfall, humidity and
latitude, must all in the last resort have determined man’s health and welfare.29
Earth’s climate is changing with the global temperature now rising at a rate
26 Mike Hulme, supra note 21, p. 29. 27 The part of the Earth system comprising all ecosystems and living organisms, in the atmosphere, on land (terrestrial biosphere) or in the oceans (marine biosphere), including derived dead organic matter, such as litter, soil organic matter and oceanic detritus. 28 Koos Verbeek and Rik Leemans, ‘Finding Facts for Policy Makers: IPCC’s Special Reports and the Third Assessment Report’, Change 54, Oct-Nov. 2000, pp. 2-3. 29 Dr. R. Kumar, Environmental Pollution and Health Hazards, New Delhi: Ashish Publishing House, 1987, pp. 1-4.
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unprecedented in the experience of modern human society. Although some historical
changes in climate have resulted from natural causes and variations, the strength of
the trends and the patterns of change that have emerged in recent decades indicate that
human influences, resulting primarily from increased emissions of carbon dioxide and
other greenhouse gases, have now become the dominant factor. These climatic
changes are being experienced particularly intensely in the Arctic region30. The IPCC
(Intergovernmental Panel for Climate Change)31 has noted that “Changes in climate
that have already taken place are manifested in the decrease in extent and thickness of
Arctic sea ice, permafrost32 thawing, coastal erosion, changes in ice sheets33 and ice
shelves34, and altered distribution and abundance of species”.35
Along with world population growth and global economic expansion over the
past century, intensified human activities, particularly energy-intensive activities,
have altered the properties of the earth’s atmosphere by unlocking a vast quantity of
underground fossilized carbon and emitting it into the atmosphere in the form of CO2,
Other greenhouse gases such as methane, nitrous oxide and a variety of halocarbons
have also been injected into the atmosphere by humans, and land cover changes have
impaired the capacity of parts of the biosphere to sequester atmospheric carbon into
living biomass36. This has altered the functioning of the global climate system37.
30 The Arctic is a polar region located at the northernmost part of the Earth. The Arctic consists of the Arctic Ocean and parts of Canada, Russia, the United States (Alaska), Denmark (Greenland), Norway, Sweden, Finland, and Iceland. The Arctic region consists of a vast, ice-covered ocean, surrounded by treeless permafrost. 31The Intergovernmental Panel on Climate Change (IPCC) is the international body for assessing the science related to climate change. The IPCC was set up in 1988 by the World Meteorological Organization (WMO) and United Nations Environment Programme (UNEP) to provide policymakers with regular assessments of the scientific basis of climate change, its impacts and future risks, and options for adaptation and mitigation. 32 Ground (soil or rock and included ice and organic material) that remains at or below 0°C for at least two consecutive years. 33 A mass of land ice that is sufficiently deep to cover most of the underlying bedrock topography, so that its shape is mainly determined by its dynamics (the flow of the ice as it deforms internally and/or slides at its base). An ice sheet flows outward from a high central ice plateau with a small average surface slope. The margins usually slope more steeply, and most ice is discharged through fast-flowing ice streams or outlet glaciers, in some cases into the sea or into ice shelves floating on the sea. There are only three large ice sheets in the modern world, one on Greenland and two on Antarctica, the East and West Antarctic Ice Sheets, divided by the Trans-Antarctic Mountains. During glacial periods there were others. 34 A floating slab of ice of considerable thickness extending from the coast (usually of great horizontal extent with a level or gently sloping surface), often filling embayment in the coastline of the ice sheets. Nearly all ice shelves are in Antarctica, where most of the ice discharged seaward flows into ice shelves. 35 Robert W. Corell, ‘Challenges of Climate Change: An Arctic Perspective’, Ambio, Vol. 35, No. 4, ‘The Royal Colloquium: Arctic under Stress: A Thawing Tundra’, June 2006, p. 148 36 The total mass of living organisms in a given area or volume; dead plant material can be included as dead biomass.
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According to the assessment report of the Intergovernmental Panel on Climate
Change, the earth’s climate system has demonstrably changed on both global and
regional scales since the pre-industrial era, with at least some of these changes clearly
attributable to human behavior.38
Studies consistently find evidence of an anthropogenic signal in the climate
record of last 35-50 years, despite uncertainties in forcing due to anthropogenic
aerosols39 and natural factors. Recent climate-model40 experiments show that natural
causes of global temperature variability cannot, on their own, explain the observed
surface warming of about 0.6°C. On the other hand, when these experiments are
repeated using rising historic concentrations of greenhouse gases and shifting
distributions of sulphate aerosols, much better agreement between observed and
modeled global patterns of temperature change is achieved. Hence, the IPCC Third
Assessment Report concluded that: “there is new and stronger evidence that most of
the warming observed over the last 50 years is attributable to human activities”.41
The theory that certain human activities contribute to warming of the earth’s
atmosphere which will bring about changes in the world climate having serious long-
term physical, biological, economic and social consequences, has been put forward by
climatologists for over 100 years. It is only recently, however, that some scientists
specializing in the great variety of aspects involved in climatic studies began to evince
serious concern that the warming process was so far underway, following the 37 The climate system is the highly complex system consisting of five major components: the atmosphere, the hydrosphere, the cryosphere, the land surface and the biosphere, and the interactions between them. The climate system evolves in time under the influence of its own internal dynamics and because of external forcings such as volcanic eruptions, solar variations and anthropogenic forcings such as the changing composition of the atmosphere and land use change. 38 Mike Hulme, supra note 21, pp. 24-25. 39A collection of airborne solid or liquid particles, with a typical size between 0.01 and 10 μm that reside in the atmosphere for at least several hours. Aerosols may be of either natural or anthropogenic origin. Aerosols may influence climate in several ways: directly through scattering and absorbing radiation, and indirectly by acting as cloud condensation nuclei or modifying the optical properties and lifetime of clouds. 40 Climate model (spectrum or hierarchy) is a numerical representation of the climate system based on the physical, chemical and biological properties of its components, their interactions and feedback processes, and accounting for all or some of its known properties. The climate system can be represented by models of varying complexity, that is, for any one component or combination of components a spectrum or hierarchy of models can be identified, differing in such aspects as the number of spatial dimensions, the extent to which physical, chemical or biological processes are explicitly represented, or the level at which empirical parametrizations are involved. Coupled Atmosphere-Ocean General Circulation Models (AOGCMs) provide a representation of the climate system that is near the most comprehensive end of the spectrum currently available. There is an evolution towards more complex models with interactive chemistry and biology. Climate models are applied as a research tool to study and simulate the climate, and for operational purposes, including monthly, seasonal and inter annual climate predictions. 41 Mike Hulme, supra note 21, p. 26.
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dramatic growth in world population, industrialization and other factors, that dire
consequences for humankind might already be irreversible. Scientific rather than legal
studies have thus dominated research in this field to date.42
“Climate change” means a change of climate which is attributed directly or
indirectly to human activity that alters the composition of the global atmosphere and
which is in addition to natural climate variability observed over comparable time
periods.43
2.2 Global Warming
Global warming, an important aspect of climate change is primarily a
consequence of accumulation of greenhouse gases in the atmosphere. Climate change
is the general term for any persistent change in climate, occurring over decades.
Global warming is one particular type of climate change. 44 The term “global
warming” is a specific case of the more general term “climate change” (which can
also refer to “global cooling”, such as occurs during ice ages). In principle, “global
warming” is neutral as to the causes, but in common usage, “global warming”
generally implies a human influence.45
‘Global warming’ means increase in the temperature of the earth and
according to various reports, the global average near surface temperature has
increased by about 0.5°C over the past 100 years. Scientists believe that this global
warming trend is resulted from the enhanced greenhouse effect. 46 The earth’s
atmosphere alone is being barraged by the effects of almost every human activity
imaginable; from our diets and farming practices to the way we heat and energize our
homes, travel, work and recreate. Projected increase in atmospheric concentrations of
anthropogenic GHGs could have an adverse impact on the earth’s temperatures.47
Global warming became one of the biggest scientific issues during the 1980s.
It has continued to attract scientific attention and also political and public concern.
Global warming is the name given to the possible climatic effect of an increasing
42 Patricia Birnie, International Environmental Law and Global Climate Change, 1st edn, London: Graham & Trotman Publishers Group, 1991, p. 1. 43 UNFCC Article 1(2). 44 Nigel Arnell, supra note 24, p. 1. 45 http://en.wikipedia.org/wiki/global_warming accessed on 12th May, 2012. 46 Dr. Sukanta K. Nanda, Environmental Law, 1st edition, Allahabad: Central Law Publications, 2007, p. 324. 47 R. Ramachandran, ‘The Play of Environmental Politics’, the ICFAI Journal of Environment Law, Vol. 11, Jan. 2003.
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concentration of “greenhouse” gases, primarily carbon dioxide, methane and nitrous
oxide. In the most general terms, these gases are transparent to incoming short-wave
radiation, but they block outgoing long-wave radiation, leading to an increase in both
surface radiation and surface temperature. These increases in turn, it is hypothesized,
lead to changes in climate.
The first speculation that a greenhouse effect might occur was by the Swedish
chemist Svante Arrhenius in 1897, although it did not become a topic of popular
debate until some 90 years later. Concentrations of the greenhouse gases are so named
because they act like the panes of glass in a greenhouse and have been increasing as a
result of human activities such as the burning of fossil fuels, deforestation48, the
application of fertilizers and the growth of particular types of agricultural production.
Water vapor is also a greenhouse gas: although its concentration in the atmosphere is
not directly affected by human activity, it does increase with temperature, and
therefore tends to reinforce the effect of the other greenhouse gases.49
The increased amounts of CO2 and other GHGs are the primary causes of the
human-induced component of global warming. They are released by the burning of
fossil fuels, land clearing and agriculture, etc., leading to an increase in the
greenhouse effect.
2.2.1 The Green House Effect
Certain gases in the atmosphere have similar properties to panes of glass in a
greenhouse: they freely let in the sun’s radiation but allow little heat to escape from
the earth. These gases are called greenhouse gases and their effect is known as the
greenhouse effect. The ‘green house effect’ is a natural feature of our atmosphere and
is the basis for identifying and reducing emissions of gases that contribute to an
increased greenhouse effect. Without it, the average temperature at the earth’s surface
would be -18°C. The earth’s climate is driven by solar radiation50. In the long term the
energy absorbed from the sun must be balanced by outgoing radiation from the earth
and the atmosphere. Part of this outgoing energy is absorbed and re-emitted by radio-
active atmospheric gases (‘greenhouse gases’), thereby reducing net emission of
48 Conversion of forest to non-forest. For a discussion of the term forest and related terms such as afforestation, reforestation, and deforestation see the IPCC Special Report on Land Use, Land-Use Change and Forestry. 49 Nigel Arnell, supra note 24, p. 1. 50 Electromagnetic radiation emitted by the Sun. It is also referred to as shortwave radiation. Solar radiation has a distinctive range of wavelengths (spectrum) determined by the temperature of the Sun, peaking in visible wavelengths.
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energy to space. To maintain the global energy balances, both the atmosphere and the
surface will warm until the outgoing energy equals the incoming energy. This is the
greenhouse effect.51
The greenhouse effect is perfectly natural and has always existed since the
earth took its present form: indeed without it, the earth would be very much colder
and subject to violent fluctuations in temperature so that it would be uninhabitable.
More recently, the term greenhouse effect has taken on a new shade of meaning to
refer to an increase in greenhouse gases in the atmosphere from man-made emissions,
which is leading to more of the sun’s heat being trapped and the earth becoming
warmer.52
Human activities are substantially increasing atmospheric concentrations of
greenhouse gases. Human-made, or anthropogenic, emissions of green house gases
will enhance the green house effect, resulting on average in an additional warming of
the earth’s surface, or “global warming”. This prospect is what is meant by the term
“climate change”.
The concentration of GHGs in the atmosphere has increased significantly over
the last 200 years. The importance of individual greenhouse gases depends not only
on their concentration, but also on how effectively they trap heat and how long they
remain in the atmosphere.53 A number of anthropogenic greenhouse gases contribute
significantly to climate change, even though none is present in the atmosphere at
anything approaching the concentration of carbon dioxide. Thus the greenhouse effect
caused by the difference in absorption rates of long-and short-wave radiation makes
the earth far hotter than it would otherwise be. The general consensus is that the earth
is 33°C warmer than it would be without the natural greenhouse effect that is with the
51 P C. Sinha, Global Warming, International Encyclopedia of Sustainable Development Series, I Edition, New Delhi: Anmol Publications Pvt. Ltd., 1998, p.1. 52 Robin Churchill, Controlling Emissions of Greenhouse Gases, 1st edition, Boston: Graham & Trortman, 1991, pp. 147-148. 53 Ninety-nine percent of the atmosphere is nitrogen and oxygen; however these gases do not affect radiation or the heat energy passing through them. It is the remaining one percent that reflects, absorb and re-emit both solar radiation (incoming) and global heat energy (outgoing).
The earth itself reflects back 6% of the solar energy that reaches it, of the total energy entering the atmosphere. 31% is reflected back by clouds, aerosols and the earth. 23% is absorbed by the atmosphere and 46% heats the earth itself. The earth then releases some of the heat it has absorbed but at the lower wavelength of infrared radiation.
Certain absorbing gases, while transparent to incoming sunlight, absorb the infrared energy directed back from the earth. They radiate this energy in all directions. The top layer eventually transmits energy directly to space. However, the gases effectively trap the infrared radiation around the earth. This is called the greenhouse effect and the gases that cause it, the greenhouse gases. They include water vapor, carbon dioxide, methane, ozone and nitrous oxide.
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mixture of gases in the atmosphere that existed before the industrial revolution.54
Many of the GHGs (carbon dioxide, methane, nitrous oxide) are produced by
both natural and anthropogenic processes, and there are natural mechanisms that
remove significant amounts of GHGs from the atmosphere. However, anthropogenic
emissions have increased the total concentration of GHGs beyond the Earth’s natural
capacity to remove these gases from the atmosphere. Of these GHGs, carbon dioxide
is the most abundant in the Earth’s atmosphere due to burning fossil fuels. CO2 is the
most recalcitrant of the GHGs, since it does not decompose easily in the atmosphere
(taking anywhere from 50-200 years to decompose). This means that a significant
decrease in atmospheric CO2 levels will not be realized for many years after
anthropogenic CO2 emissions drop. Incidentally, the US has ranked first in the world
for CO2 emissions for several decades and has been responsible for about 24% of the
total world CO2 emissions for the past decade and is projected to hover between 23%
and 24% until 2025.
The most important GHG is water vapor.55 However, because the amount of
water vapor is determined by internal mechanisms within the climate system and
because the remaining greenhouse gases are largely imposed on the climate system by
external influences mainly resulting from man’s activities, international concern to
combat the greenhouse effect has discounted water vapor and focused instead on the
other greenhouse gases. These gases are principally carbon dioxide (CO2)56, methane
(CH4)57, chlorofluorocarbons (CFCs)58, ozone (O3)
59 and nitrous oxide60 (N2O). Of
54 Paul Brown, Global Warming (Can Civilization Survive), 1st edition, Hyderabad: University Press India Ltd., 1999, pp. 50-51. 55 Water vapor does not directly affect the greenhouse gas content. However, warm air can hold more moisture. As higher temperatures increase evaporation, the water vapor content of the atmosphere will increase; will form more clouds that will decrease the amount of solar warming felt on earth’s surface, offsetting the addition effect. 56 The power generation industry’s products of combustion from burning coal or natural gas fuel will then be a major contributor to the greenhouse effect. For every ton of carbon burnt, 3.7 tons of CO2 is produced. If combustion is incomplete, soot (carbon particles) is released to the atmosphere just the burning of fossil fuels added 6.2 billion tons of carbon or 23 billion tons of carbon dioxide to the atmosphere annually. Current fossil fuel burning adds about 22 billion tons of CO2 to the atmosphere annually. Global deforestation and organic decay also add to atmospheric CO2. Carbon dioxide resulting from human use produces about 5% the amount produced by nature. The concentrations would be greater, but about half of the carbon dioxide due to human activities finds its way back into the natural carbon cycle. 57 Organic material decay in the absence of oxygen produces methane. Concentrations grow at 0.7% annually and are already 100% higher than pre-industrial values. Swamp and wetlands are primary source. Rotting garbage, industrial processes and fossil fuel extraction are other sources. The digestive processes of certain insects and domestic animals, such as sheep and cattle, produce methane as a by-product. While natural wetlands, like the Florida Everglades are considered a Shrinking wilderness, rice paddy fields are on the sharp increase.
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these gases carbon dioxide is thought currently to account for about 50% of the
greenhouse effect, methane for 18%, CFCs for 14%, ozone for 12% and nitrous oxide
for 6%. According to the IPCC, approximately 75% of the atmospheric CO2
stemming from human activity (world-wide) over the past 20 years is due to burning
fossil fuel, and the other 25% is largely due to changes in land-use, mainly
deforestation. Due to an increase in atmospheric concentrations of CO2, “the globally
averaged surface temperatures have increased by 0.6 to 2 o C over the 20th century.”61
2.2.2 Comparing the greenhouse gases
By sheer volume, carbon dioxide, produced principally by the combustion of
fossil fuels, is the most important of greenhouse gases. It is responsible for about 50%
of the global warming problem. CFCs, however, also contribute to at least 15% of the
global warming. This is because the greenhouse effect of these compounds per
molecule, relative to carbon dioxide, equals several hundred to 20,000, depending on
the compound. That effect is compounded by the fact that their lifetime is 100 years
or more. Moreover, CFCs deplete the earth’s ozone layer. Other greenhouse gases
such as nitrous oxides (NO), sulphur dioxides (SO2), methane (CH4) and ozone (O3),
Atmospheric methane concentration therefore is increasing on a net basis and probably will
continue to, given current global trends. 58 Halocarbons: Halocarbons are compounds that contain chlorine, fluorine and bromine. The best know halocarbons are chlorofluorocarbons (CFCs), which have been extensively used as spray, can propellants, refrigerants solvents and foaming agents. Halons used as fire extinguishers also contribute to this group. Molecules for molecule, halocarbons are the worst greenhouse gases around. Extremely stable, the halocarbons can stay in atmospheric suspension for centuries, until they reach the upper atmosphere and are broken down by ultraviolet radiation. This in turn releases chlorine and or bromine and this depletes the ozone layer by these elements combining with it. 59 Many contradictory factors feature in the part ozone plays in global warming. In the stratosphere, ozone is produced from oxygen directly, in the presence of sunlight. Some of this ozone finds its way down to the troposphere (10 to 15 kilometers from the earth’s surface) where it stays.
Ozone acts as a protection against the detrimental effect of ultra violet radiation from the sun, as well as retains some of the sun’s heat in the upper atmosphere. Ozone is the only trace gas that significantly affects the sun’s energy transmission; the other trace gases do not. Small droplets and particles that remain suspended in the atmosphere for long periods of time are called aerosols. They include carbon soot and sulphur oxides from combustion, sulphuric acid from volcano eruptions, dust and salt from spray. About 8% of incoming solar radiation is reflected back to the atmosphere by aerosols. With ozone they absorb and retain 19% of the incoming solar energy.
In the last hundred years ozone production occurs nearer the earth’s surface as a result of reactions with nitrogen oxides, carbon monoxide, and other gaseous pollutants in the presence of sunlight. Ozone concentrations have increased by as much as 50% in many industrialized areas of the northern hemisphere where industry is heaviest. They have also inexplicably decreased in industrial areas. CFCs have decreased ozone in the stratosphere which may balance ozone increases in the troposphere. The net effect on global warming is difficult to predict. 60 Nitrous Oxide is a colorless gas with a sweet odour. Main sources of nitrous oxide emissions are nylon and nitric acid production, cars with catalytic converters, the use of fertilizers in agriculture and burning of organic matter. 61 Denis G. Arnold and Keith Bustos, “Business, Ethics, and Global Climate Change”, Business & Professional Ethics Journal, Vol. 24, No. 1/2, The Roots of the Obligation of Business to Preserve the Environment (Spring/Summer 2005), p. 105.
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the cause of acid rain62 and of smog63 in the cities, also, result from the production
and use of fossil fuels.64
Although carbon dioxide is the main greenhouse gas, the other gases are more
effective in trapping heat. One molecule of methane traps about 21 times more heat
than one molecule of carbon dioxide. The other gases are even more effective: nitrous
oxide is 150 times, ozone 2,000 times and CFCs 10.000 times more effective. These
gases also last longer in the atmosphere: methane lasts for about 10 years, CFCs for
70-110 years and nitrous oxide for 170 years. The long-lasting effect of these gases in
the atmosphere is particularly significant, because it means that whatever steps are
taken now and in the near future to reduce emissions of greenhouse gases will not
reduce concentrations of greenhouse gases in the atmosphere for several decades.
Merely to maintain concentrations of greenhouse gases in the atmosphere at current
levels would, according to the IPCC, require immediate reductions in the emissions of
the longer-lasting gases of over 60 percent.65
If we compare a molecule of all the GHGs, the CO2 molecule will have the
least contribution to the greenhouse effect. If we call CO2 a ‘baseline’, methane has an
effect of about 21 times greater. Nitrous oxides effect is 206 times greater and CFCs
have an effect 15000 times greater. By total weight, CO2 emissions are the heaviest.
Methane emissions are 1% of CO2’s and that of the other gases are still lower.
There are also the indirect effects of gases on each other. Methane for
instance, reacts with OH molecules to produce CO2 and water. If the atmospheric OH
concentration is reduced, methane will have a longer life. When CFC molecules
deplete ozone, they thus contribute to cooling as well as warming effects.
62 Acid rain is a rain or any other form of precipitation that is unusually acidic, meaning that it possesses elevated levels of hydrogen ions. It can have harmful effects on plants, aquatic animals and infrastructure. 63 Smog is a type of air pollutant. The word “smog” was made in the early 20th century as a portmanteau of the words smoke and fog to refer to smoky fog. The word was then intended to refer to what was sometimes known as pea soup fog, a familiar and serious problem in London from the 19th century to the mid 20th century. This kind of smog is caused by the burning of large amounts of coal within a city; this smog contains soot particulates from smoke, sulfur dioxide and other components. Modern smog, as found for example in Los Angeles, is a type of air pollution derived from vehicular emission from internal combustion engines and industrial fumes that react in the atmosphere with sunlight to form secondary pollutants that also combine with the primary emissions to form photochemical smog. The atmospheric pollution levels of Los Angeles, Mexico City and other cities are increased by inversion that traps pollution close to the ground. It is usually highly toxic to humans and can cause severe sickness, shortened life or death. 64 UN’s conference on Trade and development Programme on Traminatinal Corporations investment Series No 4, ‘Environmental Management in Transnational Corporations Report on the Benchmark Corporate Environmental Survey’, US, New York, 1993, pp. 101 -102. 65 Robin Churchill, supra note 52, p. 148.
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Carbon dioxide’s contribution to global warming for the past ten years is about
2 to 3 times that of methane’s and 15 times that of nitrous oxides. In terms of
percentage volume, CO2 makes up 70% of the GHGs, methane 27%, nitrous oxide 3%
and the halocarbons66 occur in traces. Increases in GHG concentrations alter the
energy budget in the lower atmosphere, resulting in higher temperatures, which in
turn mean changes in global and regional climate patterns.67
2.3 Factors responsible for Global Warming
The entire environmental issue is linked with other issues such as population,
technology, economics, and those of a political, humanitarian and social nature. Some
of the major factors arising from human development and resulting in the change in
the global climate system are the driving forces such as population and life style
which in turn includes technological development and social, political, and economic
approaches to living. These driving forces have effects, in terms of GHG emissions,
on both the natural environment and on the part of the environment that directly
supports human life.68
There are many greenhouse gases, produced by many human activities. Some
are also emitted in large quantities from natural resources. Nevertheless, it is clear that
industrial activity including manufacturing industry; energy production and supply,
transport and construction play a major role in climate change, there are other factors
directly or indirectly responsible too.
2.3.1 Population
A number of causes are responsible for the environmental degradation. The
most important cause, however, is growth of population and resultant rise in poverty.
Besides economic development, urbanization, industrialization, availability of natural
66Halocarbons are best known as destroyers of ozone; however many are also powerful greenhouse gases. Under the Montreal Protocol, emissions of halocarbons are tightly controlled and concentrations of many dual ‘ozone depleting and global warming inducing’ gases are now beginning to decline. Halocarbon is a collective term for the group of partially halogenated organic species, including the chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs), halons, methyl chloride, methyl bromide, etc. Many of the halocarbons have large Global Warming Potentials. The chlorine and bromine containing halocarbons are also involved in the depletion of the ozone layer. Most of the halocarbons encountered in everyday life – solvents, medicines, plastics are man-made. The synthesis of halocarbons in the early 1800s but accelerated when their useful properties as solvents and anesthetics were discovered. The development of plastics and synthetic elastomers led to greatly expanded scale of production. A substantial percentage of drugs are halocarbons. 67 Nigel Arnell, supra note 24, p. 14. 68 Bo R. Doos, Environmental issues requiring International Action, Environmental protection and International Law, edited by W. Lang, H Neuhold, K Zemanek, London: Graham and Trotman, 1995, p. 51.
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resources, and the lifestyle of its people also effect the environment.
World Wildlife Fund (WWF)69 International has observed: The population
explosion, sustained by human science and technology, is causing almost insoluble
problems for future generations. It is responsible for the degradation of the
environment through the pollution of the air and water; it is consuming essential as
well as non-essential resources at a rate that cannot be sustained. Above all, it is
condemning thousands of our fellow living organisms to extinction.70
Degradation of the world’s environment, income and equality, and potential
for conflict exist today because of over-consumption and over-population. If the
unprecedented population growth continues, future generations of children will not
have adequate food, housing, medical care, education, earth resources and
employment opportunities. Humankind cannot continue to grow indefinitely. We are
now adding more people to the world’s population every decade than we used to add
in a century.71
United Nations Environment Programme (UNEP)72 has warned, throughout
the world, there is copious evidence that the carrying capacity of many life support
systems is being overloaded to the breaking point. Where such systems have
collapsed, the option for the poor is starve: either to flee or to stay put and starve.”
Even before this, however, demographic pressures will likely cause large-scale
migration and urbanization, and tax the ability of many countries to provide political
stability. Among the world’s 120 governments studied for political instability, the 31
countries rated the most unstable all had high rates of population growth.
Urbanization73 will aggravate all the problems caused by overpopulation. The key
69 The World Wide Fund for Nature (WWF) is an international non-governmental organization working on issues regarding the conservation, research and restoration of the environment, formerly named the World Wildlife Fund, which remains its official name in Canada and the United States. It is the world's largest independent conservation organization with over 5 million supporters worldwide, working in more than 100 countries, supporting around 1,300 conservation and environmental projects. WWF is a foundation, in 2010 deriving 57% of funding from individuals and bequests, 17% from government sources (such as the World Bank, DFID, USAID) and 11% from corporations. 70 Richard D. Lamm, The Future of the Environment, Annals of the American Academy of Political and Social Science, Vol. 522, The Future: Trends into the Twenty-First Century (Jul., 1992), pp. 59-66. 71 Ibid. 72 UNEP, established in 1972, is the voice for the environment within the United Nations system. UNEP acts as a catalyst, advocate, educator and facilitator to promote the wise use and sustainable development of the global environment. 73 Urbanization refers to the increasing number of people that live in urban areas. It predominantly results in the physical growth of urban areas, be it horizontal or vertical. The United Nations projected that half of the world's population would live in urban areas at the end of 2008. By 2050 it is predicted that 64.1% and 85.9% of the developing and developed world respectively will be urbanized. So the
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factor of this scenario is the inability to change reproductive habits in time to avoid
overtaxing an area’s carrying capacity.
As the population grows, its direct impact on natural surroundings becomes
apparent in various ways. Housing, sub-division of land, cutting of trees, etc., put
biotic pressure on natural environment. For food, it is required to generate more
agricultural products by either destroying forests to use the land for cultivation or
using more fertilizers and pesticides for more production leading to various
environmental problems and specially affecting the earth’s climate system.
2.3.2 Industrialization
All industrial activities involve some energy consumption, but there are large
differences in energy consumption between industrial sectors, depending on their
energy intensity and the sole of production. Economic and population growth have
proceeded much faster, with the result that over all energy use has increased. This, in
turn, means that the pattern of the energy used is the main determining factor carbon
dioxide emissions; especially since world energy demand is largely met by burning
fossil fuels. Use of commercial energy is ubiquitous in developed countries. Released
enormously, global energy demand has multiplied merely 18 times in this century and
that developed countries are the main energy users.74
Industrial Activity, specifically the burning of fossil fuels, accounts for most
of the exponential increase in emissions that has occurred since 1860. It is estimated
that, over the period 1980-1989, fossil fuel burning released 5.4 billion tonnes of
carbon per year, while deforestation, the other main anthropogenic source of carbon
dioxide, led to emission about 1.6 billion tones. The growth of commercial energy use
is closely related to the growth of industry. The continued upward trend in carbon
dioxide emissions is not the only challenge to be faced if harmful climate change is to
be avoided. There are a number of other significant anthropogenic greenhouse gases,
many of them emitted substantially as a result of industrial activity.
Industry is responsible for a significant proportion of anthropogenic methane
emissions, most human made methane is emitted by agriculture a biomass burning,
but about one third is thought to come from gas drilling and transmission, waste
landfills and coal mining. Methane is the major component of natural gas, so leaks
term urbanization can represent the level of urban development relative to overall population, or it can represent the rate at which the urban proportion is increasing. 74 ‘The Greenhouse Effect; Facts and Figures’, UNEP, Industry and Environment, Jan-Mar. 1994, p. 6.
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and deliberate venting of gas inevitably lead to emissions; methane is emitted from
waste landfills as a result of anaerobic decay of organic wastes.
Industrial activity is also an important cause of emissions of several more
minor, but still important, greenhouse gases. Fossil fuel combustion leads to
emissions of nitrous oxide and almost all anthropogenic nitrogen oxides are produced
by fossil fuel burning, with a small amount also from agricultural activities such as
biomass burning. Some industrial process, particularly the manufacture of nylon also
emits nitrous oxide. In countries with significant nylon manufacturing industries, this
can be the largest single source of nitrous oxide emissions. The power generation
industry will add considerably to the CO2 content as the demand for fossil fuel
burning power plants is realized in the developing world.75
Anthropogenic carbon monoxide (CO) emissions derive from incomplete
combustion of fossil fuels and biomass. Non-methane hydrocarbons (volatile organic
compounds) are produced anthropogenically by biomass and fossil fuel burning and
the use of solvent. All these pollutants react with sunlight in the atmosphere to
produce tropospheric Ozone (O3), another important GHG thereby aggravating
climate change. 76
2.3.3 Deforestation
Deforestation is also considered a major contributor to global warming. This
problem is linked to those of land tenure and availability. The causes of deforestation
include population pressure for agricultural land, the demand for industrial timber
production and export, and inappropriate government policies regarding land tenure,
economic incentives, forest settlement, and other population Issues.77
Deforestation also drives climate change. Forest soils are moist, but without
protection from sun-blocking tree cover they quickly dry out. Trees also help
perpetuate the water cycle by returning water vapor back into the atmosphere.
Without trees to fill these roles, many former forest lands can quickly become barren
deserts. Removing trees deprives the forest of portions of its canopy, which blocks the
sun’s rays during the day and holds in heat at night. This disruption leads to more
75 Claires M Soares, Environmental Technology & Economics”, London: Butterworths, 1999, p. 349 76 Ibid, p. 8. 77 P. R. Trivedi, K Chery Sudharshan, “Global Climate Change: An Internal Perspective”, World Environmental Science Series-4, New Delhi: Common Wealth Publications, 1995, p. 53.
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extreme temperatures swings that can be harmful to plants and animals.78
It is believed that carbon dioxide once made up the majority of the
atmosphere. Because these gases trapped so much of the sun’s heat the earth was a
very warm place. It began to change when plants; or tiny specks of living things, used
the carbon dioxide and the energy in sunlight together with the minerals and the,
nitrogen to grow. They discharged oxygen back into the air as a waste product.79
Over billions of years they evolved and grew into larger plants. All the time
they were taking CO2 out of the atmosphere, turning it into carbon and using it to
build leaves and stems. Thus they fixed the carbon in masses of vegetation that in turn
became vast jungles that sunk back into the swamps. 80 Thus green leaves and
vegetation play a critical role in climate change.
During photosynthesis 81 , plants use CO2 and give out oxygen, thereby
reducing atmospheric carbon dioxide. It is said that a big tree uses 1.75 tonnes of
carbon dioxide and releases 2.25 tonnes of oxygen per hour. Land plants create a huge
carbon “sink”82 as they suck carbon dioxide out of the air to build leaves, wood, and
roots. The sink various from year to year, but on an average, it soaks up one-quarter
of the annual CO2 emissions from the burning of fossil fuels.83 If the atmosphere had
not changed because of plants and had remained heavily laced with carbon dioxide, it
is estimated that the world would be 45°C (113°F) hotter than it is now.84
Today, one of the primary drivers of deforestation is the conversion of forests
into agricultural land to feed the world’s growing population. About 50% of today’s
agricultural land has been converted from forest areas in the last 100 years.85
78 http://environment.nationalgeographic.co.in/environment/global-warming/deforestation-overview/ accessed on 21st Dec. 2013. 79 Paul Brown, supra note 54, p. 54. 80 David W. Lawlor, Photosynthesis, 3rd edn, New Delhi: Viva Book Pvt. Ltd., 2001, p. 355. 81 The process by which plants take carbon dioxide from the air (or bicarbonate in water) to build carbohydrates, releasing oxygen in the process. There are several pathways of photosynthesis with different responses to atmospheric carbon dioxide concentrations. C3 plants: Plants that produce a three-carbon compound during photosynthesis, including most trees and agricultural crops such as rice, wheat, soybeans, potatoes and vegetables. C4 plants: Plants that produce a four-carbon compound during photosynthesis, mainly of tropical origin, including grasses and the agriculturally important crops maize, sugar cane, millet and sorghum. 82 A carbon sink is a natural or artificial reservoir that accumulates and stores some carbon-containing chemical compound for an indefinite period. The process by which carbon sinks remove carbon dioxide (CO2) from the atmosphere is known as carbon sequestration. Public awareness of the significance of CO2 sinks has grown since passage of the Kyoto Protocol, which promotes their use as a form of carbon offset. 83 ‘That sinking feeling’, Deccan Herald, May 7, 2013, Spectrum supplement, p. 4. 84 Paul Brown, supra note 54, pp. 54-55 85 ‘Where have all the trees gone?’, Deccan Herald, May 7, 2013, Spectrum supplement, p. 4.
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Forests, which store 20-100 times more carbon per unit area than croplands,
play a critical role in the terrestrial carbon cycle. Each year at least 11.3 million (and
perhaps as high as 15 million) hectares of forest are cleared in the tropics. The rate of
deforestations combined with the exalting growth in demand for forest products is
such that while 33 tropical countries are currently net exporters of wood products, this
may decline to fewer than 10 by the end of the century. If this trend could be halted
and reversed, tropical forests could serve as a vast carbon sink, reducing CO2 levels.
Deforestation has killed hundreds of thousands of species by taking away the
habitat that those species are living in and are adapted to. When trees grow, they take
in CO2 because they need it make the carbohydrates, fat and proteins that are used to
make up the tree. But when trees decompose after they have been cut down, they
release that CO2 back into the atmosphere (increasing the greenhouse effect and thus
accelerating global warming).86
The world is losing its natural forests. So much so that deforestation
contributes more to global carbon emissions every year than the transport sector. Yet
trees are a natural environmental power house. The oxygen they produce removes air
pollution, lowers temperatures and adds moisture to the air. By holding soil in place
and reducing run-off from streams, they prevent soil erosion, control avalanches and
mitigate desertification. 87 With forests storing 283 gigatonnes of carbon in their
biomass alone, curbing deforestation and re-planting trees – is a highly effective way
to reduce carbon emissions.88
Loss of tropical rain forests in the Amazon basin, Central Africa, Indonesia
and other parts of the world has been a pressing environmental issue for two decades,
but the debate has been framed largely in two ways. First, that the loss of the forests
accelerates worldwide climate change by removing a large carbon sink that absorbs
carbon dioxide from the atmosphere. Second, that the deforestation destroys the
86 Dr. S. C. Deb, Environmental Management, Mumbai: Jaico Publishing House, 2003, p. 113. 87 Land degradation in arid, semi-arid and dry sub-humid areas resulting from various factors, including climatic variations and human activities. The United Nations Convention to Combat Desertification defines land degradation as a reduction or loss in arid, semi-arid, and dry sub-humid areas, of the biological or economic productivity and complexity of rain-fed cropland, irrigated cropland, or range, pasture, forest, and woodlands resulting from land uses or from a process or combination of processes, including processes arising from human activities and habitation patterns, such as (i) soil erosion caused by wind and/or water; (ii) deterioration of the physical, chemical and biological or economic properties of soil; and (iii) long-term loss of natural vegetation. 88 Emma Back and Catherine Cameron of Agulhas: Applied Knowledge; Our climate, our children, our responsibility; the implications of climate change for the world’s children; report written for UNICEF UK. p. 32.
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livelihoods of indigenous communities.89
Loss of forests has the biggest effect on the rural poor, for whom forests serve
as “safety nets.” They contribute to poverty reduction and sustainable livelihoods by
providing food, wood fuel, medicines and non-wood products used in the house-holds
of millions of the world’s poorest people or sold in traditional or informal sector
markets. The UN report expresses its concern that deforestation poses a serious threat
to environmental sustainability90 and is jeopardizing progress towards poverty and
hunger eradication.91 On a local and regional scale deforestation will cause a wide
range of environmental damage in addition to the rapid loss of an economically
valuable natural resource like increased erosion of soils, a reduction of the capacity of
the soils to hold water, resulting in increased frequency and severity of floods and a
change of the regional climate.
2.3.4 Desertification
Desertification is a widespread environmental problem that directly affects
over 100 countries on all the inhabited continents. It occurs when productive land in
arid92, semi-arid, or sub-humid dry land regions is degraded by human activities and
by climate variations such as prolonged drought. Dry lands cover around one-third of
the world’s land surface and are inhabited by more than one-sixth of its population.
Every year the world’s population increases by 90 million; and every year 25
billion tons of top soil is lost. The expansion of deserts is linked to the destruction of
forests. Globally we are in the process of skinning the planet alive. Forty years ago,
Ethiopia had a 30% forest cover; 12 years ago, it was down to 4%; today, it may be
1%. Seventy-five years ago, India’s forests covered over half the country; today, they
are down to 14%. In 1961, Thailand’s forests covered 53% of the country; twenty-five
89 ‘Deforestation to hit hydroelectric projects’, Deccan Herald, May 28, 2013, Spectrum , p. 4. 90 Environmental sustainability involves making decisions and taking action that are in the interests of protecting the natural world, with particular emphasis on preserving the capability of the environment to support human life. Environmental sustainability forces businesses to look beyond making short term gains and look at the long term impact they are having on the natural world. You need to consider not only the immediate impact your actions have on the environment, but the long term implications as well. For example, when manufacturing a product, you need to look at the environmental impact of the products entire lifecycle, from development to disposal before finalizing your designs. 91 ‘Forests disappearing at alarming rate, says UN ‘, Deccan Herald, July 7, 2013, p. 11. 92 A region is arid when it is characterized by a severe lack of available water, to the extent of hindering or preventing the growth and development of plant and animal life.
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years later, in 1986, they covered only 29% - and were going fast. In the tropics today,
10 trees are being cut for every one planted. In Africa, the ratio is 29 to 1.93
For the millions of people whose livelihoods depend on the productivity of these
marginal areas, desertification creates additional environmental stress. Declining
vegetation and soil quality can result in the release of carbon. These effects are small
compared to impact of global energy use, although at the national level they may be
the most important source of greenhouse gas emissions for certain states.
Thus Desertification may influence global climate change by altering the
emission and absorption of greenhouse gases and also contributes to a variety of
global environmental problems, including greenhouse-gas-induced climate change,
loss of biodiversity and pollution of international waters. Global climate change may
also in turn accelerate desertification if higher temperatures increase evaporation or if
rainfall decreases.
2.3.5 Agriculture
Agriculture contributes to the emission of GHGs through three primary means
rice cultivation, nitrogenous fertilizer use, and enteric fermentation94 in domestic
animals. Estimates place the annual contribution of the cultivation and domestic
animals at approximately 20 and 15%, respectively of global methane production.
Global methane emissions from rice and enteric fermentation increase about 35% and
65% respectively, by 20-25; and N2O emission from fertilizer use are projected to
increase by 133% by 2025. It has been found out the emission from all three
categories i.e., emissions from rice, enteric fermentation, and nitrogenous fertilizer
would increase by approximately 40%, 125% and 175%, respectively by 2100.95
Rice is grown during the warm, humid season between June and October and
wheat in the cold, dry months from November to March. A major farming practice
followed in Asia is the rice-wheat system (RWS)96 under which the two cereals are
grown one after the other on the same piece of land. The use of such combine
93 Jim Mac Neill, ‘The Greening of International Relations’, International Journal, Vol. 45, No. 1, The Greening of World Politics (Winter,1989/1990), pp. 1-35. 94 Enteric fermentation is a digestive process by which carbohydrates are broken down by microorganisms into simple molecules for absorption into the bloodstream of an animal. It is one of the factors in increased methane emissions. 95 P. R. Trivedi, K Chery Sudharshan, supra note 77, p. 54. 96 Rice-wheat rotations are the most important cropping system of the Indo-Gangetic plains. The expansion of rice–wheat cropping that occurred under the green revolution, and turned Punjab and surrounding states into the food bowl of India, has led to degradation of the natural environment.
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harvester in India for rice and wheat is also generating millions of tones of crop
residue every year. To dispose the waste, farmers usually burn it. This causes
significant loss of nutrients in the soil and destroys its microbes97, besides adding to
greenhouse emissions according to a study by scientists from Delhi based National
Physical Laboratory and the Rice Wheat Consortium of the International Maize and
Wheat improvement Center in Mexico.98
In India, livestock accounts for 78% of the total methane emissions from the
agricultural sector and 50% of emissions overall. India has a per capita cattle
population of 185 cattle/1000 people. Methane is produced during fermentation of
feed in the stomach. Methane emission from livestock in India has been found to be
much lower than the estimates of the IPCC: 46 kg per animal per year. A recent study
estimates that the amount is much less-between 20 kg and 33 kg, taking into account
state-wide variations in methane emission per animal per year, also called the
methane emission coefficient.
Keeping methane in aerobic conditions and creating unfavorable conditions
for its generation by turning the manure often can decrease methane generation by 30
to 40 % if properly followed, and for this Country-specific methane emission factors
were first developed in 1992 for the agricultural sector and improved thereafter.99
Global warming is a major concern due to increase in atmospheric
concentration of greenhouse gases, mainly due to anthropogenic activities. Methane is
one of the most harmful greenhouse gases and India and China have been accused of
being the largest emitters of methane. Indian scientists on the other hand have been
trying to make more accurate estimations of methane emissions from livestock and
agriculture.
2.3.6 Vehicular Pollution
Air pollution can be attributed broadly to rapid industrialization, energy
production, urbanization, commercialization, and an increase in the number of
motorized vehicles. Vehicles are a major source of pollutants in cities and towns.
Apart from the sheer numbers, other factors contributing to the increasing vehicular
pollution in urban areas include the types of engines used, age of vehicles, density of 97 A microorganism or microbe is a microscopic organism, which may be a single cell or multicellular organism. 98 ‘Poor soil, Global Warming’, Down to Earth, Feb. 28, 2005, p. 21. 99Archita Bhatta, ‘Errors of Emission: New research finds Indian Cattle Produce Less Methane’, Down to Earth, Jan 15, 2007, p. 36.
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traffic, road conditions, and the status of automotive technologies and traffic
management systems.100
Ozone in the lower atmosphere layer called the troposphere101 is regarded as a
serious pollutant that can cause respiratory problems, and even damage masonry and
agricultural crops. The principal originating source is the emissions from road
vehicles. These include the exhaust gases such as nitrogen oxides, non-methane
volatile organic compounds and carbon monoxide. Ozone is the product of these
gases participation in a complex series of chemical reactions where sunlight and heat
act as catalysts. Summer months are generally worse for ozone.102
But going by a recent report from Center for Science and Environment
(CSE)103, the uncontrolled vehicular growth on Indian roads is causing very visible
impact on the environment. The report talks of how the car industry is pushing diesel
cars in the name of fuel-efficiency, even when these cars are several times more
polluting than petrol cars. India’s most popular small diesel car is more than 20-30%
less fuel-efficient and 50% more polluting than its counterparts in Europe, said the
report.104
Summers in Delhi are now predicted to be more polluted than winters because
the nature of vehicular and domestic emissions has changed, leading to production of
more oxides of nitrogen, the culprits that trigger heightened chemical reactions in the
summer heat. According to the World Health Organization (WHO)105, Delhi is one
among the top ten most polluted cities in the world and almost all-major Indian cities
are above the prescribed standard limit of the SPM (Suspended Particulate Matter).
The vehicular pollution accounts for nearly 70% of the total air pollution in India.
There by affecting the climate system.
100 Dr. S. C. Deb, supra note 86, p. 104. 101 The lowest part of the atmosphere, from the surface to about 10 km in altitude at mid-latitudes (ranging from 9 km at high latitudes to 16 km in the tropics on average), where clouds and weather phenomena occur. In the troposphere, temperatures generally decrease with height. 102 ‘London’s clue to stubborn ozone levels’, Deccan Herald, Dec.18, 2012, Spectrum Supplement, p.4 103 The Centre for Science and Environment (CSE) is a public interest research and advocacy organization based in New Delhi. CSE researches into, lobbies for and communicates the urgency of development that is both sustainable and equitable. CSE’s efforts are specifically designed to create awareness about problems and propose sustainable solutions. 104 Jayalakshmi K, ‘Guilty or Not?’, Deccan Hearlad, Science & Technology, March 13, 2007, p. 3 105 The World Health Organization is a specialized agency of the United Nations that is concerned with international public health. It was established on 7 April 1948, with its headquarters in Geneva, Switzerland. It is responsible for providing leadership on global health matters, shaping the health research agenda, setting norms and standards, articulating evidence-based policy options, providing technical support to countries and monitoring and assessing health trends.
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2.3.7 Ozone Depletion
The creation and destruction of ozone is a regular natural process, which never
disturbs the equilibrium level of ozone in the stratosphere.106 But when the destruction
of ozone exceeds the level of ozone creation, serious consequences are bound to crop
up due to disequilibria in the level of ozone. Any change in the equilibrium level of
the ozone in the atmosphere will adversely affect life in the biosphere.107
Ozone depletion describes two distinct but related phenomena observed since
the late 1970s: a steady decline of about 4% per decade in the total volume of ozone
in Earth's stratosphere (the ozone layer), and a much larger springtime decrease in
stratospheric ozone over Earth’s Polar Regions. The latter phenomenon is referred to
as the ozone hole. In addition to these well-known stratospheric phenomena, there are
also springtime polar tropospheric ozone depletion events.
The details of polar ozone hole formation differ from that of mid-latitude
thinning, but the most important process in both is catalytic destruction of ozone by
atomic halogens. The main source of these halogen atoms in the stratosphere is photo
dissociation of man-made halocarbon refrigerants, solvents, propellants, and foam-
blowing agents (CFCs, HCFCs, freons, halons). These compounds are transported
into the stratosphere after being emitted at the surface. Both types of ozone depletion
have been observed to increase as emissions of halo-carbons increased.
CFCs and other contributory substances are referred to as ozone-depleting
substances (ODS). Since the ozone layer prevents most harmful UVB wavelengths
(280–315 nm) of ultraviolet light (UV light) from passing through the Earth’s
atmosphere, observed and projected decreases in ozone have generated worldwide
concern leading to adoption of the Montreal Protocol108 that bans the production of
CFCs, halons, and other ozone-depleting chemicals such as carbon tetrachloride and
trichloroethane. It is suspected that a variety of biological consequences such as
increases in skin cancer, cataracts, damage to plants, and reduction of plankton
populations in the ocean’s photic zone may result from the increased UV exposure
106 The highly stratified region of the atmosphere above the troposphere extending from about 10 km (ranging from 9 km at high latitudes to 16 km in the tropics on average) to about 50 km altitude. 107 Dr. S. C. Deb, supra note 86, p. 119. 108 The Montreal Protocol on Substances that Deplete the Ozone Layer was designed to reduce the production and consumption of ozone depleting substances in order to reduce their abundance in the atmosphere, and thereby protect the earth’s fragile ozone Layer. The original Montreal Protocol was agreed on 16 September 1987 and entered into force on 1 January 1989.
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due to ozone depletion.109
The ozone layer serves as a shield protecting the troposphere and earth’s
surface from most of the ultra violet radiation found in the sun’s rays. If these ultra
violet rays reach the earth’s surface in full intensity, all exposed bacteria would be
destroyed; plants and animal tissues would be severely damaged. In this protective
role, the presence of ozone layer is an essential factor in man’s environment
especially the global climate system.110
2.3.8 Consumption patterns
Industrial processes enable swift production of different commodities;
improvements in transportation, logistics, and information technologies resulted in an
increasing volume and variety of goods and services sold in the market place and the
emergence of new forms of markets.
Consumerism111 plays a role in securing the economic and individual well-
being. Consumer choices and actions may influence social and environmental
relations at the time of purchase and use, or in the future. Similarly, consumer actions
may impact environments positively or negatively in local contexts (such as in
households and communities), or at a distance (for example, via connections through
production or disposal processes.
Concern about carbon dioxide and other greenhouse gas emissions and their
contribution to global warming have coincided with a continuing recognition of limits
to growth based on the use of nonrenewable resources, and evidence of the negative
impacts of commodity consumption on the environment. The global proliferation of
commodities and consumerism has become a source of social and environmental
concern. The promotion of green commodities as a distinct alternative to other goods
and services are available in the market under the concept of green consumerism
which intends to reduce harmful effects on the environment in relation to the
production or consumption processes.
For example: It is estimated that, on a global average, 18 to 20% of the
electricity produced is used for lighting and 80% of the lighting is done using in
candescent bulbs. In an incandescent bulb the electric current passing through the fila- 109 http://en.wikipedia.org/wiki/Ozone_Depletion accessed on 12th March, 2014. 110 Environmental Pollution: Sources and effects, Civil Services Chronicle, special edn, 2012, p. 95. 111 Consumerism is sometimes used in reference to the anthropological and biological phenomena of people purchasing goods and consuming materials in excess of their basic needs, which would make it recognizable in any society including ancient civilizations.
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ment heats it up to about 2500o C. The heat excites the atoms in the filament causing
it to emit light. In the process, however, nearly 90% of the electricity is converted to
waste heat, making the bulb highly energy inefficient.
Presently High Pressure Sodium Vapour (HPSV) lamps are in the wide use in
most of the cities and towns of our country. They are available in many versions. The
250W and 150W type are popularly used. The actual wattage used depends on the
type of street.112 More than 60% of the global electricity is obtained by burning coal.
The seven thermal power plants in Raichur each producing 210 Megawatts burn about
21,000 tons of coal every day. Every ton of coal burnt produces 3.7 tons of CO2, in
addition to other pollutants like oxides of sulphur and nitrogen. According to an
estimate by Scientific American every Kwh of electricity produced releases 0.25 kg of
carbon. Hence, switching over to CFL can have global impact.
The latest avatar of the florescent lamp is the compact fluorescent lamp
(CFL)113. They are small user friendly and can be flitted into existing bulb holders
without the need for additional fixtures. But critics point out that used CFLs during
recycling may release mercury, one of the most toxic elements, to the environment.
However, according to a report from the General Electric Company it is about four
times less than the quantity of mercury released during coal burning to produce the
amount of electricity required to use an incandescent bulb. Henc