Greenhouse Gases and Global Warming | Essay | Geography

Read this essay to learn about how the emissions of greenhouse gases in the atmosphere lead to global warming. Also learn about the management methodologies adopted for reducing global warming.

Essay on Greenhouse Gases and Global Warming:

The ecological cycles maintain the concentration ranges of the normally present atmospheric greenhouse gases, through emission and absorption by natural sources and sinks respectively. However, the increase in the emission of greenhouse gases by expanding sources and the decrease in the absorption by sinks have led to monotonous increase in greenhouse gases in the atmosphere.

The increase in greenhouse gas concentration at far greater rate than that would occur through natural processes, shall increase the atmospheric temperature at a higher rate, alter the natural carbon and other cycles, and upset the ecological balance. The atmospheric temperature rise would also adversely affect the climate across the globe.

The main sources of anthropogenic emissions include the industries, such as, power generation, transport, manufacturing industries (steel, aluminum, cement, chemical, paper & pulp) and agriculture. Anthropogenic activities, such as deforestation, pollution of water resources, destruction of biomes, are mainly responsible for the shrinkage in the capacities to absorb greenhouse gases by the major sinks like forests and ocean.

The management methodologies to negate existing faster rate of global warming include emission control by the industries while improving absorption capacities of the major sinks. Emission control by various industrial sectors include innovative processes to produce more by using less energy and the use of alternative green fuels. The measures to improve sink capacities include prevention of deforestation and destruction of other biomes along with afforestation and preservation of flora and fauna.

Fourth IPCC report in 2007 warns that serious effects of warming have become evident; and the cost of reducing emissions would be far less than the damage they will cause.

Salient features on origin and significance of global warming by GHGs are as follows:

i. The Earth’s atmosphere have different layers and the layer just above the earth’s surface, called troposphere dictates weather on the Earth. This layer contains 99% of fixed gases (mainly nitrogen and oxygen) and the rest consists of variable quantities of gases like carbon dioxide and moisture. Variations in the quantities of these two residual gases cause weather change.

ii. Weather is the prevailing condition of the atmosphere with respect to temperature, pressure and precipitation. Long time average of weather over the years is climate. An important factor in determining climate is atmospheric temperature. Planetary rotation results in the development of three atmospheric circulation cells in each hemisphere rather than one.

These three circulation cells are known as the Hadley cell, Ferrell cell and Polar cell. From equator to poles, these three distinct patterns of wind circulation are present at around 30° apart in latitude on either side of the globe. The temperature decreases from equator to poles, and the average temperature in each zone results in different climatic regions.

The globe is divided into six climate regions in the three circulatory cells based on average temperature and precipitation values. The increase in average temperature in any region would affect the temperature in other regions due to wind circulation and heat exchange amongst the regions. Therefore, the effect of high GHG emissions in any circulatory cell would be felt in others.

iii. Solar beams are responsible for heating the atmosphere. Harmful UV-ray of solar beam is filtered by ozone layer in the stratosphere. The heat producing infra-red portion of the solar beam is absorbed by ubiquitous carbon dioxide thus providing the necessary heat to the atmosphere in order to keep the ambient temperature at optimum level.

Solar beams produce plant’s food by photosynthesis converting absorbed carbon dioxide into carbohydrate, thus reducing atmospheric carbon dioxide content. Thus solar beam while responsible for heating the atmosphere is essential for heat sinks to absorb carbon dioxide by photosynthesis.

iv. Carbon dioxide, responsible for heat absorption by the atmosphere has been found to be steadily increasing over the years. The convincing data on the increase of greenhouse gases in the atmosphere were collected for the first time by Charles David. Keeling, an US Scientist, who is considered as the father of global warming issues.

v. Some gases in the atmosphere, such as, carbon dioxide and methane are similar to ‘green house’ or enclosed glass vessel, since they allow the visible sunlight to come through, while absorbing heat from the solar beam, and are therefore called greenhouse gases. The different greenhouse gases differ in their global warming potentials and life cycles. The higher is the heat absorbing capacity and longer they stay in the atmosphere, greater is the heating effect. The increasing quantities of man-made or anthropogenic GHGs are responsible for global temperature rise.

vi. The world’s major communities, classified according to the predominant vegetation and characterized by adaptations of organisms to that particular environment are called biomes. Biomes can be grouped in six major types, each of which provides space for different communities of flora and fauna with congenial atmospheric/climatic/soil conditions to their growth. Biomes are responsible for keeping the ecological balance and maintaining of optimum quantities of carbon dioxide in the atmosphere. Hence they need to be preserved.

vii. The four major spheres of natural activities on the Earth include geosphere, biosphere, hydrosphere, and atmosphere. To these natural spheres, another addition is anthrosphere or the areas of human activities. All these areas are inter­linked with each other in their activities.

The major activities include natural cycles, such as, carbon, nitrogen, water and food cycles, cover flow of material through these spheres. Oceans are the largest reservoir of water, occupying 70% of the Earth’s surface. Water vapor belongs to GHG family and thus its formation leads to trapping of heat by the ocean surface.

Evaporation leads to increase humidity and the rain. Rainwater mostly falls on ocean and rest eventually finds its way to ocean. Ocean currents move both vertically and horizontally, thus tending to equalize temperature in different zones. Phytoplankton in the ocean water acts as sink for carbon dioxide by photosynthesis.

Nature provides us the ideal atmosphere in which we live in harmony with all other biomes and other spheres. However the activities in man-made sphere, i.e., anthrosphere have affected all other spheres, such as biosphere (de-forestation), geosphere (depletion of mineral resources, degradation of soil quality), hydrosphere (pollution of water by industries) and atmosphere (GHG emissions).

In recent times, the increased activities in anthrosphere have greatly affected the natural cycles and activities in the other spheres leading to a large increase in greenhouse gases in the atmosphere. Anthropogenic GHG emissions, if not managed within a reasonable limit, may significantly change the climate with accompanying hazards.

Essay on Greenhouse Gases and Global Warming (Management Methodologies):

The basic information on the origin and significance of global warming provide the keys in formulating management strategies & guidelines to control global warming by limiting emissions.

1. Limit Emission:

Management efforts need to be directed towards the reduction of anthropogenic or man-made, enhanced greenhouse gas emission within certain limits. The stipulated emission limits have been set by Kyoto Protocol to the signatories to reduce their collective emissions of six greenhouse gases by at least 5 per cent of 1990 levels by 2012. The signatory countries have set their emission reduction targets and accordingly assigned the emission limits to individual industries and organizations. The limits for industrial sectors are set according to their current emission figures.

The EU figure on CO₂ emissions by various sectors are given in table 8.1. Similar trend in emissions is expected in other industrialized countries. Industries and transports are the major emitters accounting for almost 86% of the total emissions. In EU (group of major industrialized nations & signatories to Kyoto Protocol) major carbon dioxide emitters include the energy sector (34%) and transport (27%) (table.8.1).

These two vital sectors account for more than 61% emissions and therefore need special attention. Other industries account for less than a quarter of total global emissions, although the worst emitters like cement & steel plants belong to this group. The basic trend is similar across the globe.

The methodology to be adopted to limit emission in each sector would depend on type and other characteristics of the sector. Fossil fuels are major sources for energy generation as well as emissions. The improvement in energy efficiency is an important factor in controlling emission.

2. Increase or Preserve Absorption Capacities of Sinks:

The nature can possibly cope with, if not fully at least partly, some extra quantities of anthropogenic GHGs in the atmosphere, the amount depending on the available resources for absorbing GHGs in bio-, hydro- and geo- spheres. However human activities have led to depletion of resources in these spheres, thus restricting their capacities to deal with extra GHGs.

Along with controlling emissions, it is necessary not only to prevent depletion but also encourage enrichment of resources in other spheres, which are responsible for directly or indirectly acting as sinks. Two most important sinks are the forest and ocean. Each one can absorb enormous quantities of carbon dioxide. The preservation of resources like forests, ocean and associated flora and fauna can lead to absorption of higher quantities of greenhouse gases.

Twin objectives:

With the twin objective of reducing emission and enhancing sink capacities, the management techniques require to adopt comprehensive measures, including those stipulated in the Kyoto Protocol and beyond.

We cannot give up our necessities of traveling by car or rail or plane, neither we can give up using electricity, gas etc., in our home. For sustaining these and other activities and to cater to the needs of growing population, we need industries to grow, infrastructures to be built and the urbanization to continue.

The best management practice is to find out the ways and means to minimize the greenhouse effect in keeping up with increasing industrial and other activities required by the growing population across the world. The current practices need to be oriented towards savings in energy, while looking for alternate green source of energy.

United Nations Framework Conventions on Climate Change, from Rio to Bali have provided basic norms to minimize greenhouse gas emissions, which the participating nations are expected to follow. Agencies like ‘Intergovernmental Panel on Climate Change’ (IPCC) have been established in 1988 jointly by the World Meteorological Organization and the United Nations Environmental Programme, to oversee the activities connected with the stipulations made at various conventions at national and international levels.

3. Developmental Activities to Counter Global Warming:

While it is the collective responsibility of the corporate, societies and government to reduce energy consumption, encourage afforestation, preserve water resources, and reduce depletion of non-renewable resources, the challenges to scientific communities involve development of viable technologies for energy conservation and reduction of GHG emissions.

The Kyoto Protocol was enacted in February 2005 and thus legally obligates, all the signatories (mainly industrialized nations), to reduce greenhouse gas emission by 6% of 1990 figure. Japan established NEDO (New Energy and Industrial Technology Development Organization) where extensive work has been carried out on ‘global warming countermeasures’.

The NEDO report covers voluntary energy conservation action plans for each sector and global warming technology (energy conservation technology and GHG emissions reduction technology). EU sponsored R&D programmes on these areas have also contributed substantially in developing counter-measures for global warming. Countries like USA and Australia, although not signatories to Kyoto Protocol are also actively pursuing the development work on counter measures to global warming.

Major steps in managing global warming:

The few major steps in the management of global warming include the followings:

1. Reduce man-made emissions of greenhouse gases by reducing energy consumption and capping the emitted GHGs. Use alternatives to ozone depleting GHGs.

2. Develop alternate sustainable source of energy based on solar radiation, wind and hydroelectricity, which are completely green and partly green bio-fuel.

3. Conserve forests and actively support aforestation. Forests with its diverse plants and animal is a major sink for carbon dioxide.

4. Conserve water resources, particularly, the sea water constituting 3/4^th of the earth, from pollution. Sea water, like forest is a buffer and can absorb large quantity of greenhouse gases.

5. Ensure longer life of equipments & machineries, so as to reduce the carbon footprints of the products. This step also leads to conservation of material and energy by reducing the need for new equipment’s and machineries.

The methodologies adopted to manage global warming are to be discussed along with the guidelines provided in Kyoto Protocol.

The brief outlines of the management of global warming are as follows:

i. Global efforts to formulate strategies on the management of global warming have been discussed in various conventions sponsored by the UN and other international bodies. A major convention is the Kyoto Protocol, which has made significant contributions in the management of global warming.

ii. Limiting Carbon Emissions is mandatory to signatories of Kyoto Protocol & voluntary for other nations. It is necessary to follow the standard methods for determination of the quantities of greenhouse gas emissions and the approved methods of reporting in emission reductions. Economic incentive in terms of carbon credit has been the prime mover in reducing emissions as can be seen by the ever growing market for trading on carbon credit.

iii. Geosequestration of carbon dioxide, by large emitters has been of some help in reducing the release of carbon dioxide to atmosphere. Clean coal technology is also aimed at reducing carbon-dioxide emission.

iv. Current energy sources are mainly based on fossil fuels. The efforts are being directed towards improving power generation efficiencies of plants using fossil fuels. The hydroelectric power generation is not only the zero-emitter of carbon dioxide, but also based on alternative clean and sustainable resources.

Other alternative zero emitting energy sources such as, solar beam, and wind power are yet to be commercialized as large scale alternative to fossil fuels Nuclear power generation does not involve carbon dioxide emission but is not based on sustainable resources. The development and use of biofuels from various sources have been stepped up.

v. Large number of manufacturing and construction industries, such as, mineral products (steel & aluminum), chemical industry, metal production, cement production, with very high emission figures in their efforts to cope with mandatory and or voluntary emission cuts have introduced innovative processes.

vi. Transportation industries, including, automobiles, aircrafts, shipping have been active in reducing emission either by making the process more fuel efficient or using alternate fuel. Efforts are being made by automobile manufacturers to reduce GHG emissions per liter of fuel consumed either voluntarily or to conform to mandatory limits set by various countries, such as EU.

Research efforts are directed towards reducing transmission losses which can be as high as 40% in automobiles. Aircrafts industry has introduced measures to increase fuel efficiency and also to use partly alternative fuel. Fuel efficient engines have been introduced in the diesel run ships.

vii. Biomes are the important sinks for GHGs, esp., forests and oceans.

Forest management is an important subject in the context of global warming in view of fast depleting tropical forests. Carbon atlas shows high carbon storage associated with biodiversity, hence protection of flora and fauna constitutes an important part in preserving forest and ocean resources.

Ocean absorbs both direct heat through evaporation from the surface as well as absorption of heat plus carbon dioxide in photosynthesis by phytoplankton. Efforts are being directed towards the use of seeding process for the growth of phytoplankton.

i. Agricultural practices result in GHG emissions through enteric fermentation, manure, rice cultivation, and field burning of agricultural residue. Appropriate methods are available to reduce GHG emissions.

ii. Management of waste include recycling, reuse and proper treatment & disposal of the waste materials. Recycling of metallic waste reduce carbon footprints of products made, such as stainless steel made from utilizing 70% stainless steel scraps.

iii. Business has grown in the area of carbon project, green marketing, green trading and green projects (e.g., building, power plants) and ecotourism indicating positive growth in the carbon reduction area. Markets for trading carbon directly or indirectly have steadily grown.

iv. Corporate Social Responsibility is the buzzword today esp., in the area of corporates’ involvement in global warming Current practice of Corporate undertaking voluntary responsibilities for cutting down the emission figures in their corporations would in long run provide the solution pertaining to the problem of global warming without cutting down the GDP.