文章翻譯

1、Coolroofs:ManyoftheroofsacrossLondonaredarkincolourprobablyreachtemperaturesinexcessof5060oConhotsunnydays.Consequentlytheywillstereleaseaconsiderableamountofenergybackintotheatmosphere.Highrooftemperatureswillaccelerate

2、thedeteriationofroofmaterialsinbuildingswithporoofinsulationcontributetoincreaseddemfcoolingenergyadecreaseinindothermalcomftonupperflos.Incontrastcoolroofsbuiltfrommaterialswithhighsolarreflectancealbedohighthermalemitt

3、ancemayreachtemperaturesconsiderablylowerthantheirlowreflectancecounterparts.Thisisbecausetheyabsbstelesssolarenergyduringthedaythusarenotmajemittersofheatintotheurbanatmosphereatnight.Apartfromtheirreducedcontributionto

4、thedevelopmentofthenocturnalheatislcoolroofshaveobviousbenefitsfthelifetimeofroofsasexcessivecontractionexpansionisavoidedthroughadampeddailytemperaturerangeabsptionofultravioletradiationisreduced.Alsotherewillbegainsint

5、ermsofindothermalcomftthroughthereducedtransferofheatthroughroofstotheupperflosofbuildingsreduceddemfactivecoolingsystems.Toensuretheeffectivenessofcoolroofsasaclimatemanagementstrategytheirreflectivitymustbemaintainedas

6、thisdeclineswithroofageroofsneedtobekeptcleanasdirtpollutionlowerreflectivity.冷屋頂：倫敦許多建筑的屋頂顏色很深，在溫暖的天氣里溫度可能達(dá)到5060攝氏度。因此這些屋頂會儲存并釋放相當(dāng)大的能量到至大氣中，并且較高的屋頂溫度會加速屋頂材料的老化，建筑中老化的屋頂隔熱材料會消耗更多的冷量并且降低樓上的室內(nèi)熱舒適性。相比之下，由較高太陽反射率或反照率和較高的熱輻射材

7、料建成的冷屋頂，可以達(dá)到一個相對于低反射率屋頂較低的溫度。原因是它們在白天吸收并儲存較少的太陽能，因此夜間不是大氣的主要熱輻射源。冷屋頂除了控制夜間的熱島效應(yīng)外，它的壽命也更長，這是由于它對氣溫日較差的阻尼作用和對紫外線輻射吸收的減少，從而避免了過度的收縮和膨脹而造成的。同時冷屋頂減少了建筑物屋頂向上層房間傳遞的熱量和空調(diào)系統(tǒng)的運(yùn)行，因而會增加室內(nèi)熱舒適感。為了保證冷屋頂作為建筑氣候控制策略的有效性，隨著屋頂壽命的減少需要維持其反射特性

8、，并且保持屋頂清潔，因為灰塵和污染物的反射率低。GreenRoofs:Likecoolroofsgreenroofswhichconsistofagrowingmediumplantedoverawaterproofmembranecanhaveamarkedimpactontheclimateoftheupperflosofbuildingstheirimmediateenvirons.Onhotsunnydaysrooftoptem

9、peraturesmaybeupto2040oCcoolerthanaconventionalflatdarkcolouredroof.Aswellasthegainsachievedintermsofclimatethroughtheircoolingeffectasaresultofevapotranspirationgreenroofsreducerainwaterrunoffbyabsbingslowlyreleasinglar

10、geamountsofwateractasinsulatsreducenoisefupperflooccupantsincreaseurbanbiodiversitythroughprovidinghabitatspacefbirdssmallanimalsincreaseurbanaestheticscontributetoqualityoflife.Astheclimateimpactsofgreenroofsarelikelyto

11、begreatestduringprolongedperiodsofhotdryweathertheirefficacyasamicroclimatemanagementstrategywilldependverymuchonthemaintenanceofaregularprogrammeofwateringvegetationcare.Oncewaterbecomeslimitedvegetationhealthdeteriates

12、theirclimatebehaviourwillapproachthatofadrybaresoilsurfacewhichalthoughnotidealwillstillmaintaintemperaturesatalowerlevelthanthemeusualroofingmediums).像冷屋頂一樣，綠化屋頂由防水膜上培育的生長物質(zhì)組成，可以影響上層房間及其周圍氣encouragingwaterstageintheurba

13、nsurfacethusevapativecooling.Highalbedoroadspavementsmayalsohavebenefitsfnighttinestreetlighting.Asyetlittleisknownabouttheclimateimpactsofcoolpavementsatthestreetcanyontoneighbourhoodscaleasresearchonpavementclimateprop

14、ertiesisstillverymuchinitsinfancy.HoweverdemonstrationprojectsincitiessuchasPhoenixArizonahaveclearlyshowntheclimatebenefitsofcoolparkinglotsfexample.FLondondiscernibleclimateimpactsofcoolpavementscouldbeachievedflargepa

15、rkingareasterminalfacilitiesairptsurbanroadwayswithlargeexpansesofpavedsurfaceswhenresurfacingnewsurfacingisplanned.冷鋪路面：像倫敦許多的屋頂一樣，街道和小尺度的路面鋪裝使用典型的暗色冷鋪裝，它們由較高太陽反射率的材料組成，并且具有良好的透水性，所以它們對于減輕城市高溫是非常有效的辦法，它降低對太陽能的吸收和促進(jìn)城市地表水

16、的貯存因而易于蒸發(fā)冷卻。高反照率的路面和鋪裝也會對夜晚城市的燈光有益處。至今沒有人知道，作為路面氣候特性研究，鄰里尺度的街道胡同冷鋪路面的氣候影響研究還處于初期。無論如何，亞利桑那州鳳凰城的示范工程已經(jīng)清晰的顯示了冷色地面停車位的氣候益處。對于倫敦來說，在重建或新建大型鋪裝路面時，冷鋪路面的氣候影響可以應(yīng)用于大型停車場、終端設(shè)備、機(jī)場和城市道路的建設(shè)中。Skyviewfact:Inadditiontotheabovelocaltonei

17、ghbourhoodscaleinterventionswhichcanbeappliedtoexistingnewurbandevelopmentarethoseconcernedwithurbanmphologythearrangementofbuildingstransptroutes.Animptantdeterminantoftherateofreleaseofheatfromtheurbanenvironmentatnigh

18、tthustherateofurbancoolingisskyview.Thisdescribestherelativeopennessbetweenbuildings.Arestrictedskyviewasfoundfnarrowstreetstallbuildingswillpreventthefreeescapeofheatemittedfromstreetbuildingsurfaces.Thiswillcontributet

19、otheaccumulationofheatwithin‘streetcanyons’thustheelevationofairtemperatures.Inadditionifstreetsareientedatananglethatisperpendiculartotheprevailingwindduringintenseurbanheatisleventsthiswillreducethechancesofventilation

20、ofthestreetcanyonremovalofheatpollutantsthataccumulatebetweenbuildings.Fthisreasonnewdevelopmentsshouldoptimiseskyviewconsiderstreetientation.視角（天空可視）系數(shù)：除了上述鄰里尺度的相互作用，可體現(xiàn)在現(xiàn)存和新興城市發(fā)展影響中的，還有包括城市形態(tài)，以及建筑群和交通道路的布局。夜間城市環(huán)境放熱速率即城

21、市冷卻速率的決定性因素是視角。它反映了建筑物之間的開闊性。有限的狹窄街道和高樓間的視角，會抑制街道和建筑表面放熱向外的自由擴(kuò)散。這就導(dǎo)致了“街道峽谷”中熱量的堆積并因此造成空氣溫度升高。此外，如果街道朝向與風(fēng)向垂直，在較強(qiáng)的城市熱島效應(yīng)時，會減少該街道峽谷的通風(fēng)，同時減少了堆積在建筑物間熱量和污染物的排放?；谝陨显?，城市新的發(fā)展應(yīng)該優(yōu)化視角并考慮街道的走向。Heatwavedetectionpreparedness:Inparall