HIGH WATERS: Nashville, Tenn., on May 3, 2010.
Image: Mark Humphrey, AP Photo
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The Best Science Writing Online 2012
Showcasing more than fifty of the most provocative, original, and significant online essays from 2011, The Best Science Writing Online 2012 will change the way...
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In the past year floods have submerged cities as far apart as Nashville, Tenn., and Nowshera, Pakistan. An epic heat wave touched off peat fires in Moscow that wreathed the capital in smoke. A drought in northeastern China ruined the wheat crop. Blizzards left the U.S. buried in snow—and collapsed the roof of a football stadium. “It is a reasonable question: Is human influence on climate anything to do with this nasty bit of weather we’re having?” physicist Myles Allen of the University of Oxford said in a recent press briefing.
It hasn’t been an easy question to answer. But now, after years of research, scientists have begun to detect a human fingerprint in many extreme weather patterns. In a study written up in February in Nature (a sister publication of Scientific American), researchers examined daily records of rainfall, snowfall and sleet from more than 6,000 weather stations between 1951 and 1999.
They found a rise in cases of extreme precipitation, such as rainstorms that deliver 100 millimeters of rainfall or more in 24 hours. The uptick could not be explained by natural climate fluctuations; instead it more closely matched what the patterns that computer models of climate predict for increasing concentrations of greenhouse gases. Humanity, in other words, has likely loaded the weather dice in favor of severe storms.
The study suggests that record-breaking downpours, blizzards and sleet storms will continue—though by how much and how soon remain a mystery. The U.K.’s Met Office, the U.S. National Center for Atmospheric Research and other partners aim to bridge that knowledge gap by making regular assessments—much like present evaluations of global average temperatures—of how much a given season’s extreme weather is from human influence.
Linking a particular weather event to human-induced climate change remains problematic.
“We shouldn’t expect that human influence should be a factor in all of these events,” says climatologist Francis Zwiers of the University of Victoria in British Columbia, who led the research published in Nature. Still, we don’t get off scot-free.
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14 Comments
Add CommentBull-Pucky! Another attempt by the editors of Sci-Am to blame any climate change on man. When will the editors of Sci-Am get serious? At least they admit that, "It hasn't been an easy question to answer", which is an admission they haven't wanted to make in past issues of Sci-Am. All they offer is daily records of rainfall, snowfall and sleet between 1951 and 1999. Dang, Boys, that's only 48 years of record keeping. Most of the little-people alarmists only want to retrace global temperatures back to 1000 CE because they are afraid to go back any farther. BUT, we can objectively calibrate climate change as far back as the Egyptians. It is easy to use C-14 to measure tree rings for dating and eyes to measure the width of the same rings. We can establish these facts:
Reply | Report Abuse | Link to thisA. Egyptian Cooling - 750 - 450 BCE
B. Roman Warming - 200 BCE - 600 CE
C. Dark Ages Cooling - 440 CE - 900 CE
D. Medieval Warming - 900 CE - 1300 CE
E. Little Ice Age Cooling - 1300 CE - 1900 CE
F. Modern Warming - 1900 CE - Present
It is easy to see, even by the purposely blind editors of Sci-Am, that the earth has gone through many warmings and coolings and there weren't enough humans around for most of the time to make a difference to the climate. The editors quote their silly 48 years of record keeping as if they didn't have a brain. The editors fawn over the IPCC's future wacked-out predictions of dire flooding, sea-rising, and global warming as if it was a fact. It is time to get off the global warming bandwagon and become educated. It's the sun, STUPID!
They say it can't be explained by natural variation, but have only 48 years of data. I guess they are claiming that 48 years gives a complete picture of natural variation. Somehow I doubt that.
Reply | Report Abuse | Link to thisMr. Amalcr, according to your data, the pre-industrial era cycles of cooling and warming vary from 300 to 600 years. Admittedly, not lacking ample historical documentation of their catastrophic effects on human populations, you, however, failed to include historical data on Chinese and other Asian cycles of mass human extinction due to extreme weather, which do not adhere to the schedule you provided (being that they were far more frequent and devastating than can even be described by the Bible's propensity for hyperbole). Thus, if we know that Asian societies have been tragically and repeatedly decimated by the effects of climate change due to overpopulation and deforestation, then it takes very little imagination to assume that technology has bequeathed us in the West the power to recreate similar conditions of climate instability in just two or three generations what took the Asians at least 10. The above SA article merely states that the chickens have come home to roost, the all-mighty Babylon has been shaken to its very foundations, it's time to pay the piper, appointment with destiny, what goes around comes around, yada, yada, yada...
Reply | Report Abuse | Link to thisAmalcr: Most of the little-people alarmists only want to retrace global temperatures back to 1000 CE because they are afraid to go back any farther.
Reply | Report Abuse | Link to thisTrent Says: A blatantly false statement. Here take a look at the IPCC. See where they have an entire chapter devoted to palaeoclimate? Oh, look! most of the chapter is devoted to climate before 1000 C.E. Why is it you feel entitled to lie with such abandon?
IPCC Chapter 6:
http://www.ipcc.ch/publications_and_data/ar4/wg1
/en/ch6.html
AmalCr Says: It is easy to see, even by the purposely blind editors of Sci-Am, that the earth has gone through many warmings and coolings and there weren't enough humans around for most of the time to make a difference to the climate.
Trent Says: Logic Fail: Just because climate has changed in the past without human inputs does not mean human can not be changing climate now.
Soccer Days Says: They say it can't be explained by natural variation, but have only 48 years of data. I guess they are claiming that 48 years gives a complete picture of natural variation. Somehow I doubt that.
Reply | Report Abuse | Link to thisTrent Says: Argument from Incredulity. You have offered no critique of the article other than to proffer up your disbelief. You need to start trying harder. That is think harder about what you write.
Glad to see what I have always believed, coming to pass. Since the late 1960s after reading Garrett Hardin's books I was convinced that over-population would ruin our planet. I am glad to be alive to actually see it happening.
Reply | Report Abuse | Link to thisPlease do not do anything to reverse the situation. Life exists across our universe, natural selection controls the way it evolves. Every now and then lifeforms develop intelligence similar to what caused our scientific development, but it can not be allowed to proceed. We are now experiencing the limit to which natural selection will allow selective intelligent but generally stupid lifeforms to go. The irrational urge to breed undoes all the advances of the few rational minds.
So here we are living the sixth extinction, which will result in our elimination, and I love the way we deny our impending doom till it is now too late. Wish Carl Sagan was around, he would understand why he never heard from intelligent aliens.
The late Prof. Stephen Jay Gould wrote the following rejoinder against creationists: “A set of ideas that cannot, in principle, be falsified is not science.”
Reply | Report Abuse | Link to this[1981. Evolution as Fact and Theory. DISCOVER, May, p. 35]
What data set(s) would falsify the allegation of anthropogenic global warming? It seems to me, there is no weather- or climate-related event that cannot be “explained” on the basis of agw.
Bill Crofut Says: What data set(s) would falsify the allegation of anthropogenic global warming
Reply | Report Abuse | Link to thisTrent Says:
1. A twenty or more year trend of global cooling.
2. An empirically based explanation that tells why the stratosphere is cooling while the troposphere is warming.
3. An empirically bases explanation of why Winters are warming faster than Summers.
4. An empirically based explanation that explains why the Suess Effect can not explain the declining ratios of C13/c14 to C12.
That is four right off the top of my head.
Trent1492: Its not science to just make claims, you need to substantiate them. Just making a technical point.
Reply | Report Abuse | Link to thisStill no harm done, I like people like you who believe things on a whim, you assure me the outcome I desire for this little planet. A multitude of lifeforms with no one trying to outdo natural selection, seeding the rest of the universe before this planet can no longer support life, which will continue elsewhere till the universe finally dies.
Trent1492,
Reply | Report Abuse | Link to thisscientific earthling stated the case as well as anyone in my experience. However, you may wish to check out why, contrary to the so-called consensus, agw has been disputed by 9029 Ph.D. scientists and 22,458 others: http://www.petitionproject.org/
Please don't insult us with that tired petition. I took a random sample of two name from the list: The first was a pharmacist - no credentials in climate science. The second is either Nazi who is a conspiracy theorist - or an unknown scientist with no internet record. A 2001 survey of 26 randomly selected names found that only 11 then supported the petition language.
Reply | Report Abuse | Link to thisOf the 30,000 names on the list, 39 are climate scientists - the rest have other interests. The minimum requirement for signing is a B.S. With that in mind, the number of signatories represents 0.3% of the scientific population - a fairly clear minority.
There isd a very simple scientific explanation for climate change.
Reply | Report Abuse | Link to thisContrary to popular belief, the sun is NOT the centre of the solar system. However, like all its members, everything revolves around the centre of gravity (cog)of the solar system. Remember, planets of other solar systems are found by this same natural phenomenon.
When the gas giants of our system are together on the same side of their solar orbits, the sun moves away from the cog. This means that the orbital distance between the sun and the earth can vary, in extreme cases by over 2%, which gives a greater than 4% change in the amount of solar energy reasching the earth.
At present, most of the 4% variation is in northern summers and winters, because of the location of those same gas giants.
Learn to live with it, because you have another 5 to 10 years to go.
ConserVit,
Reply | Report Abuse | Link to thisPlease accept my apology for insulting you and anyone else who may have been offended by my action. It was my (mis?)understanding, the minimum requirement for signing was an M.S. Did you happen to check out how many of the 39 climate scientists have received
climate research grant funding?
Do the following statements impress you as contradictory as they seem to me?:
In a study published in the journal Nature, April 27, a global team of scientists led
by University of Miami (UM) Rosenstiel School of Marine & Atmospheric Science Associate Professor Lisa Beal, suggests that Agulhas Leakage could be a significant player in global climate variability....Recent research points to an increase in Agulhas leakage over the last few decades caused primarily by human-induced climate change.
[Threading the Climate Needle: The Agulhas System
http://www.rsmas.miami.edu/news-events/press-releases/2011/threading-the-climate-needle-the-agulhas-system
para. 1, 2]
"Linking a particular weather event to human-induced climate change remains problematic." That is true since sea level is rising. Rising sea level means that global cooling is occuring, not global warming.
Reply | Report Abuse | Link to thisEarth's poles are heated by moisture instead of sunlight. Since oceans are rising, less ice is forming at the poles, which indicates less heat transport towards the poles, which occurs as the Earth cools.
Also, we know that CO2 emissions cannot affect climate because CO2 already blocks all 15-micron photons (see Dr. Hertzberg report, Lynching of CO2).
Less moisture transport towards the poles means more rain in the United States instead.