戈尔-难以忽视的真相课件.ppt

1、Al Gores An Inconvenient Truth:A Skeptical TourBy Marlo LewisSenior FellowCompetitive Enterprise Institute1001 Connecticut Ave.NW,Suite 1250Washington,DC 20036202-331-1010mlewiscei.org“By far the most terrifying movie you will ever see.”“The whole aim of practical politics is to keep the populace al

2、armed,and hence clamorous to be led to safety,by menacing it with an endless series of hobgoblins,all of them imaginary.”H.L.MenckenWhat An Inconvenient Truth(AIT)isand is not An Inconvenient Truth(AIT)purports to be a non-partisan,non-ideological presentation of climate science and moral common-sen

3、sea meditation on“what matters.”In reality,AIT is a colorfully illustrated lawyers brief for climate alarmism and energy rationing.The only facts and studies considered are those convenient to Gores scare-them-green agenda,and he often distorts the evidence he cites.This Power Point presents a few h

4、ighlights from my Skeptics Guide to An Inconvenient Truth,available at CEI.org.Carbon dioxide(CO2):a“pollutant”?AIT introduces CO2 with a picture like this(pp.24-25).The black stuff is steam,not smoke,and CO2 is as invisible as oxygen.AIT never mentions that CO2 is plant food,an aerial fertilizer.Ri

5、sing CO2 levels help trees,crops,and green things generally grow faster and larger,produce more fruit,use water more efficiently,and resist pollution stress.Experimental data indicate that the 100-ppm increase in CO2 levels since pre-industrial times has increased average yields by 60%for wheat,33%f

6、or fruits and melons,and 51%for vegetables.An extraordinary positive externality,courtesy of the Industrial Revolution!Source:Idso et al.(2003)Kilimanjaro:a victim of global warming?AIT“blames”CO2-induced warming for the disappearing Snows of Kilimanjaro(pp.42-43).But snows have been disappearing si

7、nce 1880 due to a sudden shift from moist to dry conditions.There was“no evidence of a sudden change in temperature at the end of the 19th century.”20th century temperature records“do not exhibit a uniform warming signal.”Source:Molg et al.(2003)The Snows of Kilimanjaro have been disappearing since

8、1880decades before mankind could have had much impact on global climateMore snow disappeared before Hemmingway published his famous novel(1936)than after.Source:Kaser et al.(2004)In 1880,CO2 levels were approximately 290 parts per million,only slightly above pre-industrial levels(280 ppm).Source:Eth

9、eridge et al.(1998)Even in recent decades there has been virtually no warming at the Kilimanjaro summit Satellite measurements of air temperatures at Kilimanjaro show a trend of+0.01C/decade since 1978,essentially zero.“Rather than changes in 20th century climate being responsible for their demise,g

10、laciers on Kilimanjaro appear to be remnants of a past climate that was once able to sustain them.”Source:Cullen et al.(2006)“Within the next half-century40%of the worlds people may well face a very serious drinking water shortage”(AIT,p.58)The water that feeds Asias seven major river systems comes

11、from melting snow,not melting glacial ice.Data going back four decades show no trend in Eurasian snow cover for the months of November,December,January,February,and March.Figure based on Rutgers University Global Snow Lab Snow cover in southern China increased 2.3%annually during 1951-1997.Source:Da

12、he et al.(2006)“as Dr.Lonnie Thompsons thermometer analysis of the ratio of oxygen-16 to oxygen-18 in ice cores shows,the vaunted Medieval Warm Period MWP.was tiny compared to the enormous increase in temperatures of the last half-century”(AIT,p.64)Thompson analyzed the isotopic oxygen ratios in thr

13、ee Andean and three Tibetan ice cores.Data from four of the six cores indicate the MWP was as warm as or warmer than the late 20th century.The graph illustrates data from the Quelccaya ice core.Source:CO2Science.Org,analysis of Thompson et al.(2003)“Its a complicated relationship,but the most import

14、ant part of it is this:When there is more CO2 in the atmosphere,the temperature increases because more heat from the Sun is strapped inside.”(AIT,p.67)Ironically,Gores 650,000-year graph shows that each of the previous four interglacial periods was warmer than the present,even though CO2 levels were

15、 lower.Example:During the peak of the last interglacial(130,000-127,000 years ago),summer surface temperatures in Arctic Canada and Greenland were 4-5C warmer than the present,and large portions of Siberia were 4-8C warmer.Source:Otto-Bliesner et al.(2006)AIT implies that changes in CO2 levels were

16、the key driver of climate change over the past 650,000 years.In reality,temperature changes preceded CO2 level changes by hundreds to thousands of years.Source:Fischer et al.(1999)“And in recent years the rate of increase has been increasing.In fact,if you look at the 21 hottest years measured,20 of

17、 the 21 have occurred within the last 25 years.”(AIT,p.72)There has been no increase in the rate of warming since the mid-1970s,when the second 20th century warming period began.For the past 30 years,the planet has warmed at a remarkably constant rate of 0.17C(or 0.31F)per decade.Source:World Climat

18、e Report.Most models predict a constant warming rate.We can reasonably expect 1.7C of warming in the 21st century.“We have already begun to see the kind of heat waves that scientists say will become much more common if global warming is not addressed.In the summer of 2003 Europe was hit by a massive

19、 heat wave that killed 35,000 people.”(AIT,p.75)The 2003 European heat wave was due to an atmospheric pressure anomaly,not global warming:“This extreme weather was caused by an anti-cyclone firmly anchored over the western European land mass holding back the rain-bearing depressions that usually ent

20、er the continent from the Atlantic Ocean.it conveyed very hot dry air from south of the Mediterranean.”Source:United Nations Environment ProgramIn the U.S.,where air conditioning is prevalent,heat-related mortality has declined as urban temperatures have risen,whether due to global warming,expanding

21、 heat islands,or both.Source:Davis et al.(2003)“There is now a strong,new consensus emerging that global warming is indeed linked to a significant increase in both the duration and intensity of hurricanes.”(AIT,p.81)The jury is still out.Graphs at right show Accumulated Cyclone Energy index values f

22、or six ocean basins.ACE is a measure of a storms energy over its lifetime.Average ACE has increased in the North Atlantic,decreased in the Northeast Pacific,and changed little else.Source:Klotzbach(2006)“The emerging consensus linking global warming to the increasingly destructive power of hurricane

23、s has been based in part on research showing a significant increase in the number of category 4 and 5 hurricanes.”(AIT,p.89)Gore refers to Webster et al.(2005),who found a significant increase in the number of major hurricanes during 1970-2004.Pat Michaels found that,in the Atlantic basin,Websters t

24、rend disappears once data going back to 1940 are included.See graphs below.Scientists“Statement on the Hurricane Problem”Ten hurricane scientists including Kerry Emanuel and Peter Webster issued this statement,available at http:/wind.mit.edu/emanuel/Hurricane_threat.htm.Key points:Dont let debate ov

25、er the“possible”influence of global warming on hurricanes distract us from the“main”problem:subsidized development in high risk areas.Policymakers should reform building practices,land use policies,and insurance and disaster relief policies that promote“lemming like”behavior.This science-based persp

26、ective is absent from AIT.“Textbooks had to be re-written in 2004.They used to say,Its impossible to have hurricanes in the South Atlantic.But that year,for the first time ever,a hurricane hit Brazil.”(AIT,p.84)AIT implies that rising sea surface temperatures(SSTs)due to global warming caused Catari

27、na.In fact,in 2004,SSTs were cooler than normal during Brazils summer months(Jan.-Feb.).However,air temperatures were“the coldest in 25 years.”The air was so much colder than the water that it caused the same kind of heat flux from the water to the air that fuels hurricanes in warm seas.Hurricane Ca

28、terina hits BrazilSource:UCAR Quarterly,Summer 2005 Did global warming make the water cooler than normal and the air even colder?“Also in 2004,the all-time record for tornadoes in the United States was broken.”(AIT,p.87)Tornado frequency has not increased;rather,the detection of smaller tornadoes ha

29、s increased.If we consider the tornadoes that have been detectable for many decades(i.e.F-3 or greater),there is actually a slight downward trend since 1950.Source:National Climate Data Center“Over the last three decades,insurance companies have seen a 15-fold increase in the amount of money paid to

30、 victims of extreme weather.”(AIT,p.101)AIT presents a graph similar to the one at right.These losses are not adjusted for increases in population,wealth,and the consumer price index.Once losses are adjusted,there is no evidence of an increase in the severity or frequency of extreme weather.Source:K

31、unkel et al.(1999);Pielke,Jr.et al.(2006)AIT neglects to mention that aggregate weather-related mortality and mortality rates have declined dramatically over the past eight decades.Source:Glokany(2006)“In July 2005,Mumbai Bombay,India,received 37 inches of rain in 24 hoursthe largest downpour any In

32、dian city has received in one day.”(AIT,p.110)It is scientifically illegitimate to link any particular rainfall event to a gradual increase in global CO2 levels.If global warming were affecting rainfall in Mumbai,we would expect to see it in long-term precipitation records.Data from two Mumbai weath

33、er stations show no trend in July rainfall over the past 45 years.AIT blames global for the disappearance of Lake Chad.(AIT,p.117)Causes of Lake Chads disappearance include a change from a wet to dry climate starting in the late 1960s i.e.,during a period of global cooling,increased consumption of l

34、ake water to compensate for the drier climate,and the predictable tragedy of the commons as local users raced to consume a diminishing resource.Source:Hillary Mayell,“Shrinking African Lake Offers Lesson on Finite Resources,”National Geographic News,April 26,2001.“Temperatures are shooting upward in

35、 the Arctic faster than at any other place on the planet.”(AIT,p.126)This is what we would expect whether global warming is due to rising CO2 emissions or natural variability.Polar ice is white and reflects incoming short-wave radiation from the sun;sea water is dark and absorbs it.When sea ice melt

36、s,the Arctic ocean absorbs more radiant energy,amplifying the initial warming.Conversely,cooling expands sea ice,producing more cooling.Arctic climate swings!Arctic climate is naturally variableThe Arctic was as warm as or warmer in the late 1930s than it was at the end of the 20th century.Source:Po

37、lyakov et al.(2003)Greenland was warmer in the 1930s-1940s.Source:Chylek et al.(2006)“A new scientific study shows that,for the first time,polar bears have been drowning in significant numbers.”(AIT,p.146)“Have been drowning”suggests an ongoing problem.“Significant numbers”suggests lots of dead bear

38、senough to affect population dynamics.Actually,the study reports that four polar bears were seen floating offshore in Sep.04,apparently drowned after“an abrupt windstorm.”Source:Monnett et al.(2005)“Some scientists are now seriously worried about the possibility of this phenomenon a shut down of the

39、 Atlantic Thermohaline Circulation recurring.”(AIT,p.149)AIT refers to a cooling event that took place 8,200 years ago after an ice dam in North America broke,allowing lakes Agassiz and Ojibway to drain swiftly through the Hudson Strait to the Labrador Sea.However,that event injected more than 100,0

40、00 km3 of fresh water into the ocean,compared to about 240 km3/yr from Greenland ice melt.Sources:Barber et al.(1999);Rignot and Kanagaratnam.(2006)Is the THC slowing down?Bryden et al.(2005)say yes;Meinen et al.(2006)and Schott et al.(2006)say no.“Global warming is disrupting millions of delicately

41、 balanced ecological relationships among species in just this way.”(AIT,p.153)AIT cites a study showing that,in the Netherlands,caterpillar hatching season now arrives two weeks earlier than it did 25 years ago,making it harder for migratory birds to find food for their chicks.“As a result,”says Gor

42、e,“the chicks are in trouble.”But,the study says:“The gap between the schedules of the caterpillars and the birds has had no demonstrable effect so far on bird numbers.”Source:D.Grossman,“Spring Forward,”Scientific American,January 2004.Robins today are thriving in areas of Alaska and Canada where n

43、o robins were seen only a few decades ago.Global warming is for the birds!AIT predicts doom for coral reefs from CO2-induced warming and acidification(AIT,pp.166-69)Todays main reef builders emerged in the Mesozoic Period:CO2 levels and global temperatures were much higher.Graphic source:http:/ the

44、Baltic Seamany resorts had to be closed in the summer of 2005 as a result of toxic algae blooms.”(AIT,p.170)AIT presents three photos like this one.Yuck!An international expert panel convened by Swedens EPA concluded the blooms were due to record high levels of phosphorus(which Cyanobacteria eat),an

45、d a record low nitrogen to phosphorus ratio(giving Cyanobacteria,which process nitrogen directly from the air,a competitive edge over other plankton).Source:Eutrophication of the Swedish Seas“In KenyaI heard growing concerns about the increased threat from mosquitoes and the diseases they can transm

46、it in higher altitudes that were formerly too cold for them to inhabit.”(AIT,p.141)Malaria outbreaks were common in such northerly climes as Minnesota,Canada,Britain,Scandinavia,and Russia during the 19th century,when the world was colder.Source:Reiter,P.2001.Malaria resurgence is primary due to dec

47、reased spraying of homes with DDT,anti-malarial drug resistance,and the breakdown of public health programs,not to any ascertainable changes in climate.Sources:Roberts et al.1997.Hay,et al.2002.Outpatient treatments for Malaria at two Nairobi medical facilities during the 1920s and 1930sSource:WHO“S

48、ome 30 so-called new diseases have emerged over the last 30 years.And some old diseases that had been under control are now surging again.”(AIT,p.174)AIT does not cite any evidence or study linking those diseases to climate change.Correlation is not causation.Keyboard use has also increased during t

49、he past 30 years.“Each green splotch identified by year represents an ice shelf the size of Rhode Island or larger that has broken up since 1978.”(AIT,pp.181-182)“Size of Rhode Island”sounds very big;hence very scary.Rhode Island is the smallest state.Since 1978,the Antarctic Peninsula lost ice shel

50、ves totaling 4,825 square miles.Source:Eurekalert,“Collapse of Antarctic Ice Shelf Unprecedented,”3 August 2005.For perspective,that is 1/55th the area of Texas.Larson-B was about 1/220th the size of Texas and 1/246th the size of the West Antarctic Ice Sheet.“Two new studies in 2006 showed overall v