09202869d

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09202869d

  1. 1. LSGI4321 Individual AssignmentTopic:It has been argued that theincreasing urbanization isunsustainable.Discuss how GITcan help plan a green/low carbonsustainable city? SHEH WING YIN 09202869D
  2. 2. It is estimated that around half of the world’s population are now living in urbansettlements. (Cohen, 2005)With the increasing density of population in urbanareas,urbanizationbenefits the local communities both economically andsocially. The economy of scale,the desire to improve living condition andthedevelopment of new information technologies are the examples of thedriving forces behind this process. Because of the advantages of the economyof scale, the employment opportunities have attracted large amount of peoplefrom rural area to seekbetter job opportunities in urban area for better livingstandards. At the same time, the proximity of every household has encouragedthe development of social services and community infrastructures, which helpstrengtheningsocial network. These twofactors have been the major drivingforces inshaping societies.However, the planning of economic and socialdevelopments ismainly inshort term without paying attention to long termimpacts.Urbanization may be beneficial to society, but itcan also bring adverse impactsto the general public. Over the recent few years, the drawbacks of urbanizationhave drawn public’s attentionbecause ofthe adverse impacts brought byunsustainable urban development, such as air and noise pollution. Theamount of the emission of greenhouse gases has also caughtthe public’sattention as it is found that the composition of the atmosphere has changedgradually, which may lead to climate changes.Climate changes can poseserious threats to human beings, for example, unexpected long drought, longraining season and rise of sea level.The impacts brought by climate changeare long-term in global scale. (Ryan, Turton, 2007) The influences are moresevere in developing countries. Therefore, there is a need for governments totake measures to tackle this issue in order to stop deteriorating the situation.Thus, decision makers and planners have begun to concern about developingof an urban area or a city in a sustainable manner. According to ESRI (2007),sustainable development is “the balance of meeting humankinds presentneeds while protecting the environment to ensure the fulfillment of futuregenerations needs”. In other words, sustainable development aims at
  3. 3. achieving economic development, environmental protection, and socialwelfare in a balanced way. Since the increases in human population and thedemandfor the natural resources have never slowed down, the need to makethe planning of the society development sustainably cannot be ignoredso thatthere are sufficient natural resources for our next generations.Green, low-carbon city is anew practical concept which is deemed as one ofthe solutions to tackle climate changes. With this concept, the developmentplanning can bemade with consideringthe ecological cycle, which providesgreen and low carbon solutions indifferent aspects such as energy andtransportation.There are a number of indicators describing the concept ofgreen, low-carbon city, including the level of pollutions, the proportion of greenspace to urban areas, efficiency in using energy, the sustainability of energyused, and recycling rates (Meadows, 1999) Building a green, low-carbon citycan further benefit the social development, especially environmentalaspects.Environmental benefits include reduced pollution, which helpsimprove public health and quality of life. In addition,striking for ecologicalbalance can reduce the risks of natural hazards. For instance, more vegetationcovers can help reduce soil erosion, and hencethus reduces the risk offlooding during rainy season.As the relationship between humans and the environments involves spatialfactors, it is vital to utilize the spatial technology to conduct the developmentplanning.Geo-Information Technology (GIT) is useful in this extent astechnologies likeGIS is capable in analyzing the spatial data and realization ofterrain features by modeling and visualization.The ability of this technology inintegrating different types of spatial datahas also helpedthe planners in dealingwith the complexity involvedin the decision making processes related tosustainable development.By using GIT, decision makers will be able not only tosee the current state of the resources that they managed but also see theimpacts of their decisions and the future state of those resources.
  4. 4. To concentrate on the green and low carbon development framework, differentpolicy areas should be considered. Renewable energy andland use design willbe discussed in the following paragraphs.Renewable Energy – Wind PowerEnergy is essential for human beings to generate electricity for different uses,such as domestic use and industrial use. However, the main energy resourcesused by humans, such as fossil fuels, are non-renewable and theirsupplyislimited.In other words, the demand for energy resources is increasing due torapid population growth and non-stop developments over the world while theamount of energy resources available are decreasing rapidly. As a result, it isnecessary to developalternativesustainable energy sourcesto reduce thedependency on the existing energy sources.Renewable energy has become a suitable substitute for energy generation,which includes energy uses natural resources like solar energy and windenergy. Unlike non-renewable energy, renewable energy will not be completelyused up.Furthermore, they do not emit exhaust gas whichaccelerate globalwarming. Therefore, the trend of developing and researching on renewableenergy is expected to continue.(Hardcastle, Waterman-Hoey&Kunkle, 2009)In this essay, wind farm projectwill be usedas an example to discuss how GITcan provide assistance in the project to generate electricity via wind energy.To determine the most suitable area for the project, some criticalinformationhas to be collected, such as population statistics, the distribution of land use,wind intensitydata andthe network of transmission line. After collecting thosecritical data, different GIS tools can be used for further analysis and evaluation.To start with, the critical data may include both spatial and non-spatial data.Therefore, spatial analysis, instead of traditional analysis, should be done toanalyze the relationships between them. By knowing the relationships betweendifferentvariables, future trend may also be predicted statistically. For instance,
  5. 5. population statistics and land use distribution are calculated and collected topredict the demand for regional energy use. If some regions do not have highdemand on energy, it may not be economically efficient to carry out the projectfor those regions.Another example is to use spatial analysis to describe andshow the trend of the wind intensity for ensuringthe stable supply of wind forthe power generation system. (Martin, Purellku & Gehlhaar, 2010)In this way,spatial analysis is a useful tool in identifying the regions with high demand forenergy.Furthermore,buffering can be used to estimate whether some protected areaswill be affected.Theoretically, buffering can also be used to highlightarea withcertainproximity of the selected feature.For example, there are evidencesshowing that the construction of wind turbines will impose influence on the airpressure around a certain distance. (Mountain Communities for ResponsibleEnergy, 2010) Since birds can be easily affected by the air pressure, it isthusimportant to locate the construction areas having the least impacts on thebirds. With the data of bird populationof different districts, buffers can becreated and the areas inside the buffer will not be selected after consideringenvironmental aspect.Overlay function is another powerful tool, which can integrate different datalayersto create a new layer by combining the attributes of the datalayers. Forinstance, Harron(2008) has created a map which can overlay the windintensity layer withlayers of landscape sensitivity, archaeological and amenitydesignations. With this map, project planners can spot out thearea aroundconstraints like steep slope and historical sites.Thus,project development willnot be carried out around those constraints.Since the energy generated by a wind turbine can vary with environmentfactors, it is essential to testvoltage fluctuation and other aspects by creatingsimulation. Voltage fluctuation can then be predicted with different differentscenarios in the simulation model. In this way, solutions can be obtained for
  6. 6. dealing with the situations.Building DesignUrban heat island is one of the threats faced by humans nowadays. It isresulted from slower cooling rate in urban areas than rural areas. Hightemperature in urban areas can lead to an increase in the demand of energyfor cooling purpose.As a result, vicious circleoccurs.Since the urban heatisland is partly contributed by dense buildings in urban areas, especiallycommercial districts, buildingsshould be designed carefully consideringenvironmental aspects.To begin with, the high density buildings in these districts usually have narrowbuilding gaps, blocking the natural air flow and wind. Therefore, air ventilationis an important factor for making urban districts “cooler”. Without air flowbringing away the heat, the heat will be concentrated in the urban areas, whichwill directly increase the temperature of the whole district.Apart from ventilation,building height is another problem - high rise buildingsusually block the air flowof the low rise buildings in theirneighborhoods.Waterfront high rise building is a good example, which hasblocked the sea breeze from flowing inland.To tackle this problem, the areaplan should be designed with wider building gaps between the buildings andtheir neighborhoods with to allow the passage of breeze. In this way,simulation model can be used to test and predictthe air pathbyinputtingpotential locationsand heights of the buildings.Hence, betterlocationswithsuggested heights for the new buildings can be determined withthe minimal impacts on the natural air flow.Better air ventilation can thenbringaway the heat in the crowded areamore effectivelyto lower the overalltemperature of the entire district. Thus,less energy will be required for coolingpurpose.To sum up, not only can decision makers be able to know more about the
  7. 7. current state of the resources managed by them, but they can also understandthe impacts of their decisions and future state of those resources.Limitations of using GIT tools and techniques for the planning of a greenand low carbon cityBeyond the usefulness of GIT technology in the sustainable planningdesign,there are several challengesand obstacles that may be faced by theplanners.Firstly, the cost of data acquisition can be very high. The raster data like highresolution satellite image and aerial images are expensive products.They cancontribute around 80% - 90% of the project budget. (Masters,Hirsch & Wong,1994).After finish collecting the critical data for the project, the stageof dataprocessing is time consuming. It is due to the fact that differentdistricts havedifferent economic, social and environmentalelements.Hence, huge amount ofspatial and non-spatial data have to be collected, which needs a largeproportion of time to do the data processing throughout the project.In addition, the products of 3D animations and visualization arehardware-demanding in nature and have very large file size.If3D products arenot createdand displayed inthe computers with goodhardwarequality,this mayimpose difficulties in creating 3D products. Theproject members may need tospend a lot of time on the stage of creating 3D models, which decrease workefficiency as a whole.ConclusionSustainable development is an urgent issue to be addressed by our society.The effectiveness of GIT to provide tools and techniques to support the spatialanalysis, decision-making and spatial display for the development project hasbeen examined. To plan for a green and low carbon sustainable city, different
  8. 8. policy areas should be focused. Renewable energy and building design areused as the examples of how GIT assist in the planning of the developmentproject and it is shown that tools and techniques of GIT are useful to a largeextent.However, this technology has a number of limitations, which mayimpose challenges to the planners. To overcome the obstacles of the existingtechnology, more researches should be carried outto improve the efficiency oftools and techniques so that better urban planning can be achieved in thefuture.
  9. 9. Reference:Cohen, B. (2005). Urbanization in developing countries: Current trends, futureprojections, and key challenges for sustainability. Technology in Society,28 (2006), 63-80.Ryan, L. & Turton, H. (2007). Sustainable Automobile Transport.Cheltenham:Edward Elgar Publishing Limited.GIS for sustainable development (2007). Retrieved October 20, 2011 fromESRI, Web site:http://www.esri.com/library/bestpractices/sustainable-development.pdfMeadows, D. (1999). Indicators and information systems forsustainable development. In: Satterthwaite, D., ed. The Earthscanreader in sustainable cities. Earthscan, LondonHardcastle, A., Waterman-Hoey, S. &Kunkle,R.(2009). Renewable EnergyIndustry Trends and Workforce Development in Washington State ., .Negative impacts on Wind Farms (2010). Retrieved November 4, 2011 from,Mountain Communities for Responsible Energy Web site:http://www.wvmcre.org/neg_imapcts/neg_impacts.htmHarron, S. (2008). Planning for Wind Energy in Donegal. Retrieved November4, 2011 from Donegal County Council, Web site:http://www.donegalcoco.ie/NR/rdonlyres/21B39DE5-C26A-4885-B7AC-32206A4F37D7/0/PlanningforWindEnergyinDonegal.pdfMartin, F., Purellku, I. & Gehlhaar, T. (2010). Modelling of and Simulation withGrid Code validated Wind Turbine Models.A submission on HK’s Climate Change Strategy & Action Agenda (2010).Retrieved October 20, 2011 from Civic Exchange, Web site:http://www.civic-exchange.org/wp/wp-content/uploads/2010/12/101217ClimatePaper.pdf
  10. 10. Masters, E., Hirsch, B. & Wong, K. (1994). GPS/GIS and Space Time Data.Retrieved November 5, 2011 from The University of New South Wales, Schoolof Geomatic Engineering Web site:http://webone.novatel.ca/assets/Documents/Papers/File36.pdf

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