2018年6月英语四级听力美文：Hotter or Colder ?思维导图
Hotter or Colder ? It was once thought that air pollution affected only the area immediately around large citieswith factories and/or heavy automobile traffic. Today, we k
树图思维导图提供 2018年6月英语四级听力美文：Hotter or Colder ? 在线思维导图免费制作，点击“编辑”按钮，可对 2018年6月英语四级听力美文：Hotter or Colder ? 进行在线思维导图编辑，本思维导图属于思维导图模板主题，文件编号是：a60b1be1986c344698020967fd97d0b1
思维导图大纲
2018年6月英语四级听力美文：Hotter or Colder ?思维导图模板大纲
HotterorColder?
Itwasoncethoughtthatairpollutionaffectedonlytheareaimmediatelyaroundlargecitieswithfactoriesand/orheavyautomobiletraffic.
Today,weknowthatalthoughthesearetheareaswiththeworstairpollution,theproblemisliterallyworldwide.
Onseveraloccasionsoverthepastdecade,aheavycloudofairpollutionhascoveredtheentireeasternhalfoftheUnitedStatesandledtohealthwarningseveninruralareasawayfromanymajorconcentrationofmanufacturingandautomobiletraffic.
Infact,theclimateoftheentireearthmaybeaffectedbyairpollution.
Somescientistsfeelthattheincreasingconcentrationofcarbondioxideintheairresultingfromtheburningoffossilfuels(coalandoil)iscreatinga“greenhouseeffect”—holdinginheatreflectedfromtheearthandraisingtheworld'saveragetemperature.
Ifthisviewiscorrectandtheworld'stemperatureisraisedonlyafewdegrees,muchofthepolaricecapwillmeltandcitiessuchasNewYork,Boston,Miami,andNewOrleanswillbeunderwater.
Anotherview,lesswidelyheld,isthatincreasingparticulatematterintheatmosphereisblockingsunlightandloweringtheearth'stemperature—aresultthatwouldbeequallydisastrous.
Adropofjustafewdegreescouldcreatesomethingclosetonewiceageandwouldmakeagriculturedifficultorimpossibleinmanyofourtopfarmingareas.
Atpresentwedonotknowforsurethateitheroftheseconditionswillhappen(thoughonerecentgovernmentreportpreparedbyexpertsinthefieldconcludedthatthegreenhouseeffectisverylikely).
Perhaps,ifweareverylucky,thetwotendencieswilloffseteachotherandtheworld'stemperaturewillstayaboutthesameasitisnow.
相关思维导图模板
树图思维导图提供 904名中国成年人第三磨牙相关知识、态度、行为和病史的横断面调查 在线思维导图免费制作，点击“编辑”按钮，可对 904名中国成年人第三磨牙相关知识、态度、行为和病史的横断面调查 进行在线思维导图编辑，本思维导图属于思维导图模板主题，文件编号是：10b9a8a2dd2fb4593f8130ef16c320fc
树图思维导图提供 销售经理半年规划 在线思维导图免费制作，点击“编辑”按钮，可对 销售经理半年规划 进行在线思维导图编辑，本思维导图属于思维导图模板主题，文件编号是：e614d6bcf03e9318109240a18697c5d1
沪公网安备 31011502019485号
上海工商