Effects Of Urbanization On The Environment Environmental Sciences Essay

When worlds interact and alter the universes natural landscape it doubtless has inauspicious effects on assorted environmental facets. In relation to this essay subject I can place that urbanization likewise has damaging effects on the environment, in peculiar the urban ambiance. In order to truly understand the effects nevertheless it is critical to measure precisely what is meant by the term urbanization and later the term urban atmosphere.

Urbanization is basically the term used to mention to the physical growing in the size and distribution of metropoliss and towns. The rapid addition in the urban population came to the bow after the industrial revolution of the 18th and 19th centuries. Prior to the industrial revolution the bulk of the universe ‘s population lived and worked in the rural countryside. The outgrowth of mill occupations nevertheless acted as a pull factor and attracted people to shack in these countries. In kernel a move from rural to urban is basically what is in inquiry here and these towns and metropoliss accordingly grew in other to provide for the ever-growing urban population. The urban population soon is estimated to be turning about 2.5 times faster than the rural population. Table 1 below indicates the planetary urban population ( GUP ) of the old ages 1960, 1985, 2009 and indicates the projection of what the planetary universe population will be in 2050.

From this we can clearly see the extent to which urbanization is happening and at present merely over half of the universe ‘s population is urbanized. In fact urbanization has been happening at such a big graduated table that megacities have emerged as a consequence. Megacities refer to metropolitan countries with a population excess of 10 million and there are presently 21 megacities worldwide. A big population concentration within an country indisputably will hold damaging impacts on all environmental facets. With specific mention to the urban ambiance at that place has been much concern and it has so been the focal point of attending in recent decennaries. The urban ambiance refers to the air or atmosphere in the immediate locality of the urban country and this undoubtedly differs significantly from the rural ambiance. Urbanization along with the activities and maps of the town or metropolis have a diverse scope of effects on the urban ambiance, which accordingly can impact the local micro-climate and is so a serious cause for concern amongst scientists and conservationists likewise. From my research in this capable country I have come to the decision that there are chiefly two ways in which urbanization has an consequence on the urban ambiance ; it affects the initial temperature and micro-climate of the town or metropolis and it besides affects the quality of the air. Throughout this essay I will discourse these effects in more item whilst doing direct mentions to the instance surveies such as Atlanta, Kolkata ( once Calcutta ) and Los Angeles in order to exemplify these effects.

Harmonizing to the United Nations Department of Economic and Social personal businesss, in 2009 50.1 % of the Earth ‘s land surface was urbanized significance that merely over half of the part of the universe surface represents towns or metropoliss ( United Nations, 2009 ) . If urbanisation tendencies continue at the same gait this part is said to increase to 56.6 % in 2025 ( United Nation, 2009 ) . This may look like a little addition but metropoliss are undeniably debatable. They cause jobs within and outside the metropolis utilizing resources from the environing countries and upseting the natural landscape which as briefly mentioned earlier can hold negative effects on all environmental facets. In kernel these metropoliss and towns represent their ain clime, a micro-climate which can be easy distinguished and differentiated from environing rural countries, yet a clime which is rather complex. This is known as an Urban Heat Island ( UHI ) and is so one of the most normally discussed effects of urbanization. What is meant by this term is that the urban country by and large possesses a heater temperature than the immediate locality and this is due to a figure of grounds. First these towns and metropoliss represent an unreal environment. If we look at their urban cloth or what they consist of, we can place that they comprise of big black surfaces and stuffs including concrete edifices and pavings, tarmacadam and asphalt and by and large possess small or no flora or green countries. The reflective power, which refers to the coefficient of reflection of a surface is hence low. Their high thermic capacity and their dark nature consequences in the stuffs absorbing the heat alternatively of reflecting it back out into the ambiance. In add-on the absence of trees is a critical constituent besides. Trees shade the land and suppress the urban surfaces form absorbing the heat and hence without these soaking up degrees are increased. Industrial processes within a town or metropolis every bit good as visible radiations and air conditioning in retail units and other little industries besides contribute and generate unreal heat, impacting the overall temperature of the country ( as indicated in Fig 1. below ) .

Fig 1. Exemplifying the heat island phenomenon.

Beginning: hypertext transfer protocol: //heatisland.lbl.gov/HighTemps/

As you can see clearly from the above diagram there is a crisp addition in temperature straight over the immediate metropolis or within the urban heat island. As one moves from the urban Centre or possibly the cardinal concern territory ( CBD ) there is a general lessening with the exclusion of suburban residential countries with the addition here due to the burning of fossil fuels for usage in domestic warming. The urban-rural temperatures differ most significantly during still eventides and darks. This is chiefly due to, one time once more, the urban cloth which retains heat throughout and therefore the towns and metropoliss by and large take much longer to chill off than the rural locality. It besides has been shown that air current velocity, along with cloud screen, are the most of import meteoric parametric quantities that contribute to the strength of an urban heat island. ( Grady Dixon and Mote, 2003 ) . The being of the high edifices affects the air current form and air flow of the urban ambiance. These edifices form a unsmooth urban construction with streets and lanes dissecting these tall edifices. This is known as an ‘urban canon ‘ as these edifices represent a natural canon. Every edifice disturbs and disrupt the air flow which ab initio slows down the atmospheric air currents and consequences in metropoliss and towns being less windy than the rural countryside, once more impacting the initial temperature. However when strong air current conditions are present near tall edifices, the air is funnelled down the windward sides of these edifices, taking to an addition in wind currents and Eddies through narrow passageways ( Perry and Perry, 1986 ) and therefore ensuing in the blasts of air currents which we experience in about every metropolis today.

An first-class illustration of an urban heat island is Atlanta, Georgia which is situated in the southern US. Atlanta so has been a focal point point for survey in which to exemplify the effects of the urban heat island on the urban ambiance and later the micro-climate. In recent decennaries, Atlanta has experienced big scale urbanization and rapid growing with an explosive growing in commercial, retail and industrial services every bit good as transit services. Population increased significantly in 1000s from 101,242 in 1950 to about 261,375 in 2010 doing it the most populated urban country of south-eastern United provinces ( United Nations, 2009 ) . It was because of this big graduated table urbanization that Atlanta developed an urban heat island ( Grady Dixon and Mote, 2003: 1273 ) and it has been shown to increase and possibly incite electrical storms. Undertaking Atlanta ( Atlanta Land Analysis: Temperature and Air Quality ) , a survey funded by the National Aeronautics and Space Administration Earth Observing System ( NASA ) was established in 1996 in order to indentify, step and analyze how urbanization has impacted the micro-climate and air quality of the metropolitan country and in bend to research the relationship between the urban heat island, its induced convergence zone and electrical storm induction ( Bornstein and Lin, 1999: 507 ) As cited by Grady Dixon temperatures are 5oC greater in Atlanta than environing countries due to the urban heat island consequence ( Grady Dixon and Mote, 2003: 1276 ) . Study was carried out in Atlanta over a five twelvemonth period, 1996- 2000 during warm periods as UHI is more distinguishable during summer months. During the Atlanta Olympics of 1996, between 26 July and 3 August, six major precipitation events were recorded over the immediate metropolis within this nine twenty-four hours period and analysis has shown that Atlanta ‘s urbanization instigated or initiated these. “ Thunderstorms traveling with threading regional flows, nevertheless, tended to bifurcate and travel around the metropolis du tot its edifice barrier consequence ” ( Bornstein and Lin, 1999: 515 ) . Harmonizing to Grady Dixon since the happening of these events Atlanta and its urban heat island is said to be “ making its ain conditions. ” ( Grady Dixon and Mote, 2003: 1273 ) .

As mentioned in my debut to this try the quality of the air is another widespread consequence of urbanization on the urban ambiance. This basically refers to aerate pollution and more specifically to anthropogenic air pollution which undisputedly increases with increasing urbanization. Undoubtedly the degree of anthropogenetic air pollution is much greater within an urbanized metropolis where there is a high concentration of population and in add-on a much higher degree of activity. There are three primary ways in which anthropogenetic air pollution is increased ;

The burning of fossil fuels including coal, oil and gas in both industries and the domestic place for heat and energy.

Transportation systems and vehicles straight breathing pollutants into the ambiance.

The disposal of solid waste via incineration.

There is a broad assortment of pollutants emitted into the atmosphere day-to-day through these procedures, with each and every one holding an consequence on the urban ambiance. Some of the chief pollutants include sulphur dioxide, oxides of N, C monoxide, suspended atom affair and lead as indicated in Table 1.2 below.



Sulphur Dioxide ( SO2 )

Combustion of fossil fuels

Oxides of N ( NO+NO2 )

Combustion of fossil fuels

Carbon monoxide ( CO )

Combustion of fossil fuels


Vehicle emanations


Vehicle emanations

Suspended particulate affair

Combustion of fossil fuels and vehicle emanations.

Table 1.2. List of the chief pollutants that contribute and add to atmospheric pollution in the urban ambiance.

Undoubtedly these chemicals and atoms have a damaging impact on the urban ambiance and later the air quality of the country. For a really long period anthropogenic air pollution has been an inauspicious consequence of urbanization. Since the industrial revolution, urbanized metropoliss and towns have been fouling the Earth ‘s ambiance in a figure of ways. Smoke is the most common and the most seeable pollutant emerging from both houses and industries likewise. However it is important to observe that fume, developing from the burning of fossil fuels, viz. coal and oil contains a broad scope of other assorted unsafe pollutants and chemicals including sulfur dioxide which is a byproduct of coal, oxides of N and in add-on it besides contains gases such as C monoxide. Pollution generated by these procedures and maps becomes trapped in the heater air and is hence blown or transported across the town or metropolis. Smoke besides contributes to the formation of another pollutant known as smog. Smog is a job of quickly increasing towns and metropoliss and is so a common signifier of anthropogenetic air pollution that affects the urban ambiance. It is a combination of both fog and fume and is an index of the bed of air pollution that lies over most urbanized countries. There are by and large two types of smog referred to today ; industrial smog and photochemical smog, with both sorts holding harmful effects on the urban ambiance. Industrial smog, arising from the industrial revolution, is chiefly due to the burning of fossil fuels such as coal for heat and energy ensuing in the byproduct of sulfur dioxide being emitted in to the ambiance. The domestic usage of fossil fuels for warming intents is besides a part to this affair. Industrial smog has increased quickly over the last 300 old ages in developing states. In December 1952 London experienced ‘one of the most ill-famed smogs of recent times ‘ known as the ‘pea souper ‘ ( Pickering and Owen, 1994: 108 ) . The status continued for five yearss due to the stationary air that laid over the capital metropolis pin downing the pollutants from the burning of fossil fuels near to the land ( Jackson and Jackson, 2000: 344 ) . The 2nd type of smog is known as photochemical smog which is produced as a consequence of the burning procedure of conveyance vehicles and by and large affects countries of high sums of sunlight for illustration Los Angeles. Harmonizing to Middleton, vehicle pollution in the Los Angeles Basin has contributed significantly to the formation of smog. In 1990, Los Angeles was recognised as the ‘area with the worst quality air in USA ‘ ( Middleton, 1999:229 ) . With a population of about 14million people and 10 million vehicles in the urban country at this clip it is so conclusive as to why Los Angeles was sing such huge sums of smog. The name ‘Los Angeles smog ‘ has emerged due to the fact that this type of smog originated here and harmonizing to Jackson it is common in lower latitudes with Mexico metropolis and Baghdad amongst the worst ( Jackson and Jackson, 1994: 345 ) . It is conclusive that primary pollutants reach their maximal concentrations during the forenoon and eventide haste hours ( ibid ) .

Fig 1.2. Picture exemplifying the strength of smog in Los Angeles, California.

Beginning: hypertext transfer protocol: //www.engin.umich.edu/~cre/web_mod/la_basin/index.htm

Transport is a major issue that is straight linked to urbanization today and is so a major cause for concern. Transportation links and systems are increasing in about every metropolitan country yet ‘such mobility comes with an environmental monetary value ticket ‘ ( Middleton, 222 ) seting utmost sums of force per unit area on the urban ambiance. It is a cardinal beginning of air pollution due to its high dependence on the burning of fossil fuels ( Middleton, 1999: 227 ) and harmonizing to Ghose is the chief cause of the anthropogenetic air pollution crisis ( Ghose et Al, 2004:345 ) . Increasing urbanization within a metropolis can take to increased employment and therefore increased wealth. This has a major impact on auto ownership and in the twelvemonth 2000 the universe motor population hit a milepost when it exceeded 700 million ( Ghose, 2004: 345 ) . The chief pollutants originating from the burning of fuel in vehicles are ;

Carbon dioxide

Carbon Monoxide

Nitrogen oxides


Sulphur oxides


Suspended atom affair

Kolkata, the capital of the West Bengal State, India suffered from terrible anthropogenetic air pollution due to vehicle emanations and is believed to be one of the worst contaminated megacities in the universe ( Ghose, 2004: 346 ) . Surveies were undertaken during the period from October to December 2002 in North Kolkata in order to convey the extent to which vehicular emanations have contributed to air pollution. The northern portion of Kolkata is a residential suburb yet is place to a figure of little industries. As a consequence big figure of vehicles pass through this intersection daily, breathing the above pollutants. The survey indicated that emanation degrees exceeded their legal bound and have reached threatening degrees. 70 % of the entire pollution burden in Kolkata is chiefly due to emanations from vehicle fumess ( Ghose, 2004: 349 ) with vehicles including coachs, car jinrikishas and autos increasing at a rapid gait. In add-on it is besides important to see that India as a state is still developing and over 90 % of air pollution in developing states it attributable to transport and vehicular emanations. In add-on in developing states older vehicles is by and large what is in inquiry with hapless vehicle care, therefore ensuing in higher degrees of air pollution.

Fig 1.3 Picture bespeaking vehicle emanations which contribute to pollution of the urban ambiance.

Beginning: hypertext transfer protocol: //www.ec.gc.ca/EnviroZine/english/issues/54/feature2_e.cfm

From what I have discussed throughout this essay it is conclusive that urbanization has an consequence on the urban ambiance and it is a world-wide issue impacting both developing and developed states. The micro-climate of the urban town or metropolis and the air quality are amongst the primary jobs associated with urbanization and so are rather important. The illustrations which I discussed, Atlanta, Kolkata and Los Angeles are all clearly declarative of these effects and highlight the extent of the job and accordingly stress the demand to turn to it. Peoples have been utilizing the ambiance as a landsite for a really long clip and fortuitously are now going aware of the existent harm they are doing to our urban atmosphere. The Oslo Protocol was initiated in 1994 and so marked a considerable milepost in international control of pollution. Different marks were set for all take parting states based on the ability of the environment to digest pollution. There are ways to cut down emanations which have been put in topographic point. The most evident method for assailing the effects of urbanization is to cut down the degree of pollutant emanations from their beginnings. There are many engineerings today than can cut down emanations from power workss including fuel desulphurisation ( the remotion of sulfur from coal before firing ) , fluidised bed engineering ( cut downing emanations during burning ) and fuel gas desulphurisation ( take sulfur gases before they are admitted into the air ) .In relation to vehicular emanations catalytic convertors have been introduced and used in vehicle engines and harmonizing to Middleton this method has been successful in cut downing emanations in Los Angeles ( Middleton, 1999:230 ) . In add-on a lead-phase out program was initiated in 1970 to take lead from gasoline. This has been really successful and harmonizing to the United Nations Environment Programme leaded stage out: planetary position January 2011, the bulk of the universe is now utilizing leadless gasoline, ( therefore combating the job of urbanization and conveyance on the ambiance. Indisputably it is still a planetary job, nevertheless with more cognition and see the extent of this job could be reduced.