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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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Roughly 1,000 years ago, Europe enjoyed several centuries of balmier average temperatures. Dubbed the "Medieval Warm Period," it was the last time before the present that agriculture could flourish in Greenland. This era also shows yet again that changes to natural systems can drive local climate change—and provided fodder for countless misunderstandings about the nature of present day global warming.
But new research shows that the MWP, as it is affectionately known in acronym-happy science circles, as well as the "Little Ice Age" that almost immediately followed it (and spelled doom for the Greenland Norse) were likely the result of fluctuations in the sun's strength and the frequency of volcanic eruptions, among other natural causes.
Cores drilled from ancient ice sheets as well as of the coral reef and lake sediment varieties show that at the same time as Europe enjoyed average temperatures as warm as today, the tropical Pacific was unusually cold. This suggests that natural cycles—such as the succession of El Nino and La Nina conditions in the Pacific Ocean—forced these climate anomalies.
Unfortunately, neither the sun nor other natural cycles can entirely explain the recent warming trend that has brought potatoes back to coastal Greenland. To date, the only explanation that matches those observations are a concurrent rise in greenhouse gas concentrations in the atmosphere.
CO2 and its peers now are responsible for trapping an extra three watts per square meter of planet. And if that continues, the MWP will end up looking like an ice age.
—David Biello
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44 Comments
Add CommentGlobal Warming, is not caused by humans. In fact there hasn't been warming since 2001. Global warming is a political tool to collect money for democrats. They have been pushing this green lifestyle for the past 30 years, costing americans jobs and causing small business to go bankrupt.
Reply | Report Abuse | Link to thisYou are so wrong..even if global warming isn't caused by humans...common sense tells us that burning fossil fuels is non renewable, polluting and will eventually bring the world economy to a stand still...unless alternatives can be found..Imbiciles who stick with the status quo will have nothing left!!!
Reply | Report Abuse | Link to thisAm I the only one who finds this article to be virtually incomprehensible?
Reply | Report Abuse | Link to thisIn the first paragraph, the author refers to the MWP, when "Europe enjoyed several centuries of balmier average temperatures". Balmier than what? Current temperatures? He attributes the "balmier temperatures" (whatever they are) to solar intensity and volcanic activity.
In the third paragraph, he refers to the "same time as Europe enjoyed average temperatures as warm as today, [and] the tropical Pacific was unusually cold." He attributes these "anomalies" to El Nino and La Nina. Is this the same period as the one referred to in the first paragraph, or is it a different one? If it's a different period, when did it occur? If it's the same period, then why the change in causes? Also, if it's the same period, what was the first period "balmier" than, given that during the period in the third paragraph "Europe enjoyed average temperatures as warm as today"?
If anybody can figure this article out, please let me know.
Kilday, that is a ridiculous supposition. American democrats only make up a very small percentage of the worlds population. People around the world are concerned about Global Warming and are unlikely to be driven by some clandestine Democrat conspiracy.
Reply | Report Abuse | Link to thisFor me, I don't need all the modelling and studies that are been done to try to prove Global Warm. I simply go by two rules I leant when I was young. My mother taught me that when I was finished with a project "to clean up my mess." A little later in life when I worked on construction as a teenager my mentor taught me to "always work clean".
They are generally good rules to live by. We should all clean my our mess whenever driving a car, burning coal for electricity or pouring concrete for a new skyscraper or bridge.
Re-sending previous post to correct grammar and typos ......
Reply | Report Abuse | Link to thisKilday, that is a ridiculous supposition. American Democrats only make up a very small percentage of the worlds population. Most people don't even know who or what American Democrats are. People around the world became concerned about Global Warming on their own from their own studies and are unlikely to have been driven by some clandestine Democrat conspiracy.
For me, I don't need all the modelling and studies that are been done to try to prove Global Warming. I simply go by two rules I leant when I was young. My mother taught me that when I was finished with a project "to clean up my mess." A little later in life when I worked on construction as a teenager my mentor taught me to "always work clean".
These are generally good rules to live by. We should all clean up our mess whenever driving a car, burning coal for electricity or pouring concrete for a new skyscraper or bridge.
Since were going to go for the 'tired' blame the Democrats crap I'll jump your a**. The big business, greed gods, and the corporate thief don't want to loose. Some are just going to have to clean up and loose some luxuries so our future generations don't have to suffer, starve. and live in an environmental hell to survive. If the corporate, Republican fat asses loose their jets. So be it. That crap of yours is getting really old.
Reply | Report Abuse | Link to thisIf I didn't know better, I would say that Kilday's remark is so ridiculous, he must be a AGW supported playing the other side, trying to make the denialists look even more petty than some of them really are.
Reply | Report Abuse | Link to thisBut, back on subject - James, I agree. This was a pretty messy aricle. Should go back to the editors for a re-write after they check the facts.
The article does not make clear to me what the natural cycles are to which the comparison is made with El Nino/La Nina.
Reply | Report Abuse | Link to thisI'm with two previous posters, this article doesn't make much sense.
I agree with James Thurber. What? does this article say anything!? And to think that you can use this article to support a conservative (FOX) perspective that Global Warming is not man-made is even more of a validation that the "Science" of the right is absolutely based on rhetoric. Great post by James. Tally Ho! & Happy Thanksgiving!
Reply | Report Abuse | Link to thisI agree with James Thurber. What? does this article say anything!? And to think that you can use this article to support a conservative (FOX) perspective that Global Warming is not man-made is even more of a validation that the "Science" of the right is absolutely based on rhetoric. Great post by James. Tally Ho! & Happy Thanksgiving!
Reply | Report Abuse | Link to thisCurrently, Global Warming is effecting our daily life. Perhaps this phenomenon is not caused by us but by sun activities. Although that, I agree with the ideas of some scientists that we have responsibilites to cause that. If you want to know the reason deeply, pls reference some books and review the experts arguments here : http://www.buyusing.com/Climate-Change/ James are great one to post this !
Reply | Report Abuse | Link to thisCurrently, Global Warming is effecting our daily life. Perhaps this phenomenon is not caused by us but by sun activities. Although that, I agree with the ideas of some scientists that we have responsibilites to cause that. If you want to know the reason deeply, pls reference some books and review the experts arguments here : http://www.buyusing.com/Climate-Change/ James are great one to post this !
Reply | Report Abuse | Link to thisIt sounds more like this article is "plan B" after the hack at CRU--Plan A ( it would be nice to try to contain the putative MWP, even if we dont yet have a hemispheric mean reconstruction available that far back --Mann) having been put in some disrepute....
Reply | Report Abuse | Link to thisAs the need for alternative fuel sources grows then so too will the rate of discoveries and inventions grow to satisfy that need.
Reply | Report Abuse | Link to thisWith this fact of human nature always being applied in everything we do, there is no need to bash those who correctly label the Global Warming mongers.
What you are doing is hiding your head in the sand about the nature of politics and how Global Warming is used to maginalize parts of society.
Most Democrats are self centric to think folks will follow their lead when bashed upon with hollow facts.
OK, now this has gotten silly from both sides of the aisle.
Reply | Report Abuse | Link to thisJames Thurber claims the article is "virtually incomprehensible". Yet the author, David Biello, is perfectly clear. He points to one era, "Medieval Warm Period", when a warming trend has been detected. He claims its warming was casused by one set of natural circumstances. There is no ambiguity by his use of the word 'warming'. He compares it to local average temperatures of today by referring to crops being grown in Greenland as well as referring to ice core samples.
He allows, as a good balanced article should, that there was an exception in the Pacific at the same time. He speculates that the *cycle* of of El Nino and La Nina conditions might have caused the colder Pacific climate by overriding the natural warming for the rest of the world caused by volcanoes and Sun flares. It is all there, and not hard to follow.
His final suggestion is that current warming trends cannot be explained entirely by natural causes such as volcanos and Sun flares.
The real problem is that nothing about climate can be predicted based on historical data. We don't know enough. Nor do we fully comprehend that the real time span for major climate change is in the millions of years not some minor sub-cycle one thousand years ago. There have been two or three minor warmings and coolings within recorded history. The last ice age was 10,000 years ago. Our current over all glaciation began over 2.5 million years ago and we are probaly in a natural warming cycle within that glaciation period.
There have been estimates that man's affect has been to speed up warming by 6 to 20 years, depending on who you read or which model you choose.
All of which to me is moot. Warming is coming either sooner or a little later. We will have to act and spend trillions of rescue dollars sooner or later, by choice or by force because of climate warming -- no matter how it was caused or who is responsible.
Meanwhile, I fall back on the simple rule I mentioned in an earlier post -- clean up your mess.
Henrik Svensmark explained it to them in '96 and they didn't listen. Now Mann is saying that Global Warming causes Global Cooling on the BBC website. It's the most perverse doublethink I've ever heard, I can't stop laughing!
Reply | Report Abuse | Link to thisLet me see if I understand this. We don't really know what caused the warmer climate in the MWP or LIA but we assume it was solar, the PDO or something like that.
Reply | Report Abuse | Link to thisSimilarly, we don't really know why the current warming plateau occurred (or why it levelled off) but we assume it must be CO2. And we assume it will be really bad because it would be no fun to assume otherwise. And why are we writing about this topic now, David? Climategate emails?
I think global warming precedes ice ages. Ocean currents carrying heat to the poles need the polar ice to chill the water and cause it to sink and flow back to the equator. Once the ice is gone, the warm water can't get out of it's own way and freezing starts again.
Reply | Report Abuse | Link to thisThe earth is far more independent. How do you explain the missing long term effects from the tons of gas and debris dumped into the atmosphere during the large volcano eruptions documented in the last 200 years? Compare the volcano gases to a couple years of fuel consumption. Man is more like a flea on the back of an elephant. Let the market deliver alternatives when it becomes economical todo so.
Reply | Report Abuse | Link to thisIt can't be CO2 you geniuses, if it was CO2 it couldn't stop warming until we reach the imaginary "tipping point" when it would go arse over tit. It was the Sun all along. Search for 'the cloud mystery' on youtube, only the first 2 minutes is in Danish. Henrik Svensmark will be remembered as the man who solved the global warming problem. The sky and the Sun are proving him right as I type this.
Reply | Report Abuse | Link to thisI have read Scientific American since 1954 and have all of the magazines since 1960. I am so unhappy with the current quality of the articles that I am going to quite reading it. The September issue was a ghastly thing, so poor compared to other Sept. Special issues that I wanted to cry. They just pass on the nonsense about CO2 causing global warming. It used to be a great magazine.
Reply | Report Abuse | Link to thisThis is just one more example of how far Scientific American has fallen. I have been a constant reader since 1954 and have all of the magazines since 1960. This article of nonsense about CO2 causing climate warming and the abysmal quality of the Sept. issue have made me decide not to renew my subscription.
Reply | Report Abuse | Link to thisThe magazine is still OK for articles that do not have a connection with the political world. True, they have been dumbed down. I think this is true of other science and technology oriented publications. I know this criticism has been made against Sky & Telescope. Sometimes even the subjects with political connections get good treatment. Nuclear power for example. Mostly though its reader beware.
Reply | Report Abuse | Link to thiswould it be helpful to know the unedited version of this was written by Hockey Stick Mann? Not being as smart as many here, near as I could figure he redefined MWP to an Anomaly. The Little Ice Age that followed really meant it was much warmer in Southern Hemisphere. Essentially, to the effect, cold means hot and hot means hotter, except when talking of the past when hot means not so hot.
Reply | Report Abuse | Link to thisThat is his press release, he is supposed to release a paper today (11/27/09 Fri)
would it be helpful to know the unedited version of this was written by Hockey Stick Mann? Not being as smart as many here, near as I could figure he redefined MWP to an Anomaly. The Little Ice Age that followed really meant it was much warmer in Southern Hemisphere. Essentially, to the effect, cold means hot and hot means hotter, except when talking of the past when hot means not so hot.
Reply | Report Abuse | Link to thisThat is his press release, he is supposed to release a paper today (11/27/09 Fri)
would it be helpful to know the unedited version of this was written by Hockey Stick Mann? Not being as smart as many here, near as I could figure he redefined MWP to an Anomaly. The Little Ice Age that followed really meant it was much warmer in Southern Hemisphere. Essentially, to the effect, cold means hot and hot means hotter, except when talking of the past when hot means not so hot.
Reply | Report Abuse | Link to thisThat is his press release, he is supposed to release a paper today (11/27/09 Fri)
Those of you who did not live before the '60's cannot imagine Global Warming!!! Winters were -55degrees F, average winter snowfall was 21 feet in central BC, Canada. We now have shirt sleeve weather in January! PLEASE, wake up! I don't believe it's all "man-made", but we certainly have helped. This year may be the first year in recorded history with no summer ice in the Arctic. Oh,and FOX is NOT a pseudonym for Conservative!!
Reply | Report Abuse | Link to thisIt's hard to know what Europe or the Far East thinks about "Global Warming" when the media here in the US is so biased in protecting it's political agenda...Have you noticed how many newspapers are folding up...I think that the majority of readers are sick and tired of the BS we are fed and have stopped subscribing...Man made "Global Warming" included. And, yes, we need to find other methods energy, but because it just makes good sense to do so.
Reply | Report Abuse | Link to thisSpiff
'The little Ice Age' just goes to show the relative instability of local Climates. Before anthropic CO2 emissions, CO2 levels increased and decreased with temperature. This is because there is an equilibrium between atmospherice CO2 concentration and dissolved CO2 concentration. The lower the temperature, the more CO2 is dissolved. Today as CO2 is produced from fossil fuels, the greenhouse effect increases sea temperature, which releases more CO2 etc etc. A vicious circle sets in, leading to local climate instabilities and change. The only remedy is to decrease emissions and sequestrate CO2, for example by biomass pyrolysis. (See www.eprida.com).
Reply | Report Abuse | Link to thisGeorge Makes a valid point. There is some things that are far worse than "doing nothing". If you do not understand the cause, doing something may be far worse than doing nothing. Like the kid with a stomach ache. Instead of finding out the cause, the doctor takes out his appendix (perfectly healthy) and the kid dies from enecephalitic shock.
Reply | Report Abuse | Link to thisIt is clear there is a herd and crises mentality going on with one side of the debate since the release of the CRU emails. Now they appear to be throwing anything that will stick to the walls in order to sidetrack the debate. Instead they should be rooting out the incompetant boobs that tried to "cook the books" on the issue and get back to true scientific testing of the hypothesis (it is not theory as to advance to that stage, testing has to be done, and none have been done on AGW yet).
What? "nothing else can´t explain" is not science but a personal reflection! In science lack of a cause is never an evidence for a random other causing something.
Reply | Report Abuse | Link to thisIf you are serious David Biello, please tell the positive correlation in the article, not a negative.
Or change the name of this paper to non-scientific american.
No one is actually arguing for status-quo. Most people even know using of oil and carbon will have an end. But that does not justify false sciense what this arguing is about. Clarifying what is what makes efforts to change energy-sources easier, not harder. That is only one reason why I require following: IPCC, go back to science!
Reply | Report Abuse | Link to thisThis is the global part of it. In Sweden (where I live) 6 of 7 parties have a AGW-agenda. The game goes like this: if you want to win an election you have to have the agenda. And reverse, if you are succesful convincing the voters that there is an AGW going on then they vote at you - because you have an agenda. It seems to be a win-win situation. As long noone asks stupid questions. To avoid this, the television, the press and the radio don´t pulbish any critisism on AGW. Because if they do the subscribers, viewers and listners go away and then the money goes away. Everybody can´t win.
Reply | Report Abuse | Link to thisObviously more studies are needed. However, there does appear to be a problem with our climate and environment as a whole since the mid-1800's. Interesting to note that the Europes unusually balmy weather occurred 1000 years ago - far before the industrial revolution. What concerns me is the short time (150 years) where the earth as seen tremendous changes. It is the small period of time, where the earh and all species can not adapt. Since 150 years ago, man has moved more earth than earth. More species have vanished by man's activities compared to natural selection.
Reply | Report Abuse | Link to thisStudying hundreds of temperature diagrams around the world (in order to find a correlance time-temerature)
Reply | Report Abuse | Link to thisI found two different series in the 20:th century.
1. Temerature rises in cities and near airports.
2. Temerature is at constant level in rural areas.
http://data.giss.nasa.gov/gistemp/station_data/
-There has not been "tremendous changes" in climate.
-It is true species are vanishing because of human activity.
But AGW is not the cause of everything, not even this.
See the numbers again.
-"natural selection"? do you mean "survival of the fittest"?
Darwins theory IMPLIES that mans expansion on earth is because man is fittest. The evolutionary news are that man CARES of other species, not the opposite.
More facts please, less guessing. You can also ask questions.
Imbicils? Does the word mean what I think (I am not English spoken). In that case I want you to think twice what you call people that don´t think the same way you think.
Reply | Report Abuse | Link to thisThere are other contradictions too in the article: That shifts in the suns life does not COMPLETELY explain warm and cold periods is of course not a valent reason to assume that ALL of the changes are due to AGW. That stands clear in IPCC reports, the only wrong there is that every other reasons for warmer climate are diminished (compared to common science) but AGW is much greater. And AGW is announced as THE reason which other things can only make stronger. No other reason is accepterd as a reason "an sich". It´s not science, it´s propagande for an view.
Reply | Report Abuse | Link to thisIs there no one here, at Ipcc, in goverments - or elsewhere who had a slightes idea ot the term "equilirium"?
Reply | Report Abuse | Link to thisMost of the things humans do that makes the equilirium to change to a new level causes processes that eihter a) brings the state back to the equilium or b) gives a new equilirium. Studying IPCC reports I have found NO remark of this central word in many sciencies. For one thing: the "tipping point" is not science - it is the opposite of science.
You are totally right about negative correlation! As an accountant in Sweden I should know. The tax-law here says it is not the authorities who has to prove you are guilty (in tax-crimes). It is up to you to prove you are NOT guilty...
Reply | Report Abuse | Link to thisI am surprised and disappointed at the poor quality of this article. The author claims the Pacific had a cold period at the same time as Europe had a warm period, but does not cite the evidence. I have been on a quest to find this cold Pacific data, but found it sorely lacking, uncovering just one paper. Meanwhile, there are dozens of papers demonstrating a warm period in the Pacific rim at the same time as in Europe. In totality, there are over a hundred papers with evidence of the global nature of the MWP, including the Antarctic. Michael Mann made a comment about the Bransfield data showing a cold period from 1000-1100 CE, but the work by Khim et al on this exact field clearly shows a MWP. So it sounds like these claims of cold climate in the southern hemisphere are pure conjecture at best.
Reply | Report Abuse | Link to thisThe people at www.co2science.org have done a great job of compiling summaries of these articles, and even have a map showing the global distribution of the studies. Check out: http://www.co2science.org/data/mwp/mwpp.php
The author of this Scientific American article even says this warm period was likely due to the sun and ocean currents - clearly global effects, so it is illogical to claim the effect was only felt in Europe.
The author then says these things cannot explain twentieth century warming. Again, this is without evidence or citation. In fact, Pacific currents correlate very closely with global effects. See http://www.agu.org/pubs/crossref/2009/2008JD011637.shtml
A very poor article indeed. If temperatures were indeed warmer 1000 years ago, and this effect was global, as the evidence demonstrates, then the central claim of AGW, that recent temperatures are unprecedented, lies in tatters. Misleading the non-scientific public on this does a great disservice. The author should post a retraction.
Wake up!! You're stance on global warming is as political as the idiots who have convinced you it's man made. You and the other Demo idiots can no more change the climate than they can stop one little hurricane.
Reply | Report Abuse | Link to thisWhy isn't hydro-power not concidered renewable? Why do we not build more nuclear power plants?
Reply | Report Abuse | Link to thisDemoidiots want to take us back to riding horses and then complain because the horses aren't free.
Global warming and freezing is a cycle, live with it.
When humans are able to influence the direction or intensity of the smallest tornado, then talk to me about how we are able to influence the world's climate.
Reply | Report Abuse | Link to thisOMG!! How did you form the words common sense?
Reply | Report Abuse | Link to thisWouldn't it make more sense to utalize alternative energy sources when the current ones are exausted?