Last week we were treated to the ridiculous story about Genghis Khan having an impact (or apparently not enough) with his impact on humanity. This week, a “new interpretation”; it’s the Romans and Christopher Columbus who are the ghosts of climate injustices past by daring to enable use of forest resources. I got quite the chuckle from this part, emphasis mine:
Ignoring the progress in agriculture, the preceding models implied that the same area of land is required to feed a European living in the fifth century as in the 20th century. This is why scientists struggled in trying to estimate the amount of CO2 produced by man before the industrial era. The work of Jed Kaplan’s team now enables us – for the first time – to travel back thru time.
Wow, time travel! Here is the press release in full:
===============================================================
Man has been provoking climate change for thousands of years!
24.01.11 – The Roman Conquest, the Black Death and the discovery of America – by modifying the nature of the forests – have had a significant impact on the environment. These are the findings of EPFL scientists who have researched our long history of emitting carbon into the environment.
“Humans didn’t wait for the industrial revolution to provoke environment and climate change. They have been having an influence for at least 8000 years.” Jed Kaplan is putting forward a new interpretation of the history of man and his environment. This SNSF professor at EPFL and his colleague Kristen Krumhardt have developed a model that demonstrates the link between population increase and deforestation. The method enables a fairly precise estimate of human-origin carbon emissions before the advent of industrialization.
The story of our influence on the climate began with the first farmers. At that time, the prevailing technology didn’t allow an optimal use of the soil. “For each individual, it was necessary to clear a very large area of forest”, explains Jed Kaplan. However, with time, irrigation, better tools, seeds and fertilizer became more effficient. This development was a critical factor, which would partially counterbalance the increase in population, and contain the impact of human pressure on the natural environment.
Animation commented by Jed Kaplan
Agriculture – the story of a race for productivity
The relationship between population levels and agricultural land-use is therefore not simply proportional, as was formerly believed. In the Middle Ages, Europe had fewer forests than today, although since then the population has increased more than five fold. “The real innovation in our research has indeed been the taking into account of the improvements in farming techniques. Standard models simply state that the bigger the population, the more forest is cleared; but this doesn’t correspond to the historical reality.
Ignoring the progress in agriculture, the preceding models implied that the same area of land is required to feed a European living in the fifth century as in the 20th century. This is why scientists struggled in trying to estimate the amount of CO2 produced by man before the industrial era. The work of Jed Kaplan’s team now enables us – for the first time – to travel back thru time.
The influence of the Roman Empire and the Black Death on the climate
The results of this research tell a very different story from that which has been circulating up until now. They show, for example, a first major boom in carbon emissions already 2000 years before our era, corresponding to the expansion of civilizations in China and around the mediterranean.
Certain historical events, almost invisible in the preceding models, show up strongly in the data produced by the scientists. A good example is the re-growth of the forests as a consequence of the fall of the Roman Empire. The Black Death, a plague which resulted in the death of more than a third of the European population, also led to a fall in carbon emissions.
From the decline of the American indians to the minor ice age
Lastly, a significant decrease in emissions began in the 16th century – the one which would herald the minor ice age. Jed Kaplan has an audacious hypothesis to explain the dip in the data curve: “Thanks to the reports of the early explorers, we know that the forests were less abundant on the American continent. Then the settlers gradually eliminated the indigenous population.” Threatened with extinction, these populations effectively deserted the forested areas, which – by taking up the carbon in the atmosphere – in turn set off the legendary frosts of the 19th century. “Of course, it’s only a hypothesis”, he concludes, “but given the data we have gathered, it’s entirely plausible”.
Jed Kaplan’s model is not in contradiction with the previous ones on one critical point: the enormous increase in emissions from the beginning of the industrial era, and the massive use of fossil fuels. “We are just saying that our influence on the climate began a lot earlier than we thought. In 6000 BC, we were already accumulating significant quantities of carbon in the atmosphere, even though it was nothing compared to the situation today”, adds the scientist. A conclusion that could turn out to be critical in the future for the improved evaluation of the decisive impact of the forests on the climate.
====================================================================
This story was released via Eurekalaert. The study authors: Prof. Jed Kaplan and Kristen Krumhardt have interesting bios.
Here’s the abstract:
Holocene carbon emissions as a result of anthropogenic land cover change
Kaplan, Jed Oliver ; Krumhardt, Kristen ; Ellis, E. C. ; Ruddiman, W. F. ; Lemmen, C. ; Goldewijk, K. K.
In: The Holocene, 2010
Date: 2010
Humans have altered the Earth’s land surface since the Paleolithic mainly by clearing woody vegetation first to improve hunting and gathering opportunities, and later to provide agricultural cropland. In the Holocene, agriculture was established on nearly all continents and led to widespread modification of terrestrial ecosystems. To quantify the role that humans played in the global carbon cycle over the Holocene, we developed a new, annually resolved inventory of anthropogenic land cover change from 8000 years ago to the beginning of large-scale industrialization (ad 1850). This inventory is based on a simple relationship between population and land use observed in several European countries over preindustrial time. Using this data set, and an alternative scenario based on the HYDE 3.1 land use data base, we forced the LPJ DGVM in a series of continuous simulations to evaluate the impacts of ALCC on terrestrial carbon storage during the preindustrial Holocene. Our model setup allowed us to quantify the importance of land degradation caused by repeated episodes of land use followed by abandonment. By 3 ka BP, cumulative carbon emissions caused by anthropogenic land cover change in our new scenario ranged between 84 and 102 Pg, translating to c. 7 ppm of atmospheric CO2. By ad 1850, emissions were 325–357 Pg in the new scenario, in contrast to 137–189 Pg when driven by HYDE. Regional events that resulted in local emissions or uptake of carbon were often balanced by contrasting patterns in other parts of the world. While we cannot close the carbon budget in the current study, simulated cumulative anthropogenic emissions over the preindustrial Holocene are consistent with the ice core record of atmospheric d13CO2 and support the hypothesis that anthropogenic activities led to the stabilization of atmospheric CO2 concentrations at a level that made the world substantially warmer than it otherwise would be.
Keyword(s): agricultural intensification, anthropogenic land cover change, dynamic global vegetation model, global carbon cycle, Holocene CO2, prehistory
Reference: EPFL-ARTICLE-161674
Full paper:
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
Poor things, they are trying so hard to explain temps rising before SUV’s
The start was good then i got to the word models, when will they learn. I could not read anymore. The statement ignoring the advancements in agriculture, farms in euro. in the 5th century could feed today’s euro. just boggles the mind they would say such CRAP.
““We are just saying that our influence on the climate began a lot earlier than we thought. In 6000 BC, we were already accumulating significant quantities of carbon in the atmosphere, even though it was nothing compared to the situation today”, adds the scientist. A conclusion that could turn out to be critical in the future for the improved evaluation of the decisive impact of the forests on the climate.”
I suppose a little evidence of all that is too much to be expected of a “scientist”.
The find a decrease in carbon emmissions following the plagues of the midle ages?
Let me get this straight a 30% decrease in population and the have discovered that the carbon emmisions of the survivors decreased. Somebody paid for this study?
I seem to recall a couple of other studies out recently that also linked a change in climate to the plagues as well, something about clooler wet summers, lower crop production as a result. Lower crop production, bad nutrition a concentration of vermin and people in the urban areas no public health science to speak of can you say plague.
This whole study seems to have decided that they result of the study will be X now go justify the result with some theories.
Are they serious or just plain barking?
They’re a strange breed these environmentalists. They take examples of widllife & nature like Darmoor, Exmoor, Yorkshie moors, etc, yet these areas of outstanding beauty were actually created by man clearing the land of trees to creat arable land. Yet if you suggested that we replant the entire area with native trees there would be an outcry of anti-environment! You can’t win!
It was worse back then than we thought
I suspect Mr. Peabody and Sherman are seeking more funding for their Way-Back Machine.
….we developed a new, annually resolved inventory of anthropogenic land cover change from 8000 years ago to the beginning of large-scale industrialization (ad 1850).
———–
Large scale industrialization occurred well before 1850: Manchester was renowned for its blackened skies by the 1820s. The switch to coal-fired steam engines pre-dates the 1769 Watts engine with fairly extensive use of the Newcomen engine by 1750 for collieries, public water-works and blast furnaces. Also, the switch to coal predates 1600, and London skies and buildings were blackened by the domestic use of coal for cooking and heating. By 1800 at least 50% of air pollution was generated by domestic fires, and massive population increases meant this was a not a trivial quantity of smoke generated. Also, surely, according to their model, the increased C02 caused by deforestation, which re-emerged as a major problem by 1300 in Europe, with growing populations etc before the Black Death, should have triggered warming, not the plummeting of temperatures that occurred in the 14th century. This self-same deforestation led to the widespread use of sea coal – and then mined coal – in England from the 13th century onward. So the generation of CO2 likely did not slow much even following the Black Death – especially as the resultant increased wealth from re-distribution of property led to higher standards of living. I wonder if these researchers have looked at the historical literature?
Has anyone factored in the naturally occurring forest fires that humans have been putting out in the latter half of the 20th century?
Sounds like he’s saying the ‘Black Death’ was a good thing because it led to a fall in human carbon emissions in that era. These ‘scientists’ are truly pathetic. There’s a saying that things go from bad to worse to hilarious. Climate science has definitely gotten to the hilarious point. But it’s still annoying because I’ll bet this ‘study’ was paid for by taxpayer funds. Only governments would fund this kind of nonsense.
What you people don’t understand is that all science researchers, no matter what field, are jumping on the global warming bandwagon in a wild feeding frenzy of funds. Here is where some of the research funding went.
Warmer Northern Hemisphere winters because of global warming
Colder Northern Hemisphere winters because of global warming
Global warming to slow down the Earth’s rotation
Global warming to speed up the Earth’s rotation
North Atlantic Ocean has become less salty
North Atlantic Ocean has become more salty
Avalanches may increase
Avalanches may reduce
Plants move uphill due to global warming
Plants move downhill due to global warming
Declining coral calcification on the Great Barrier Reef due to global warming
Increasing coral calcification on the Great Barrier Reef due to global warming
Look on the bright side, we’ve lived at least 8000 years without doing anything about AGW.
Are they really suggesting that a decrease in CO2 emissions by humans brought on the Little Ice Age?
“a significant decrease in emissions began in the 16th century – the one which would herald the minor ice age.”
Are they completely ignorant of the work of Knut Angstrom, Chamberlin, and others that determined a hundred years ago that the roll of CO2 was way over estimated?
Following their logic, I suppose one might conclude that the introduction of the Chevy Volt caused the bitter cold this winter in New England and Europe.
Unbridled ridicule of these clowns would be too kind.
Yes, and so have beavers. But for some reason, humans are evil and beavers are good.
If man was influencing (by influencing, I mean somewhat significantly, not a very very tiny amount which could be possible) the climate for 8000 years, that indicates to me that it’s very sensitive to our influence. Given that the world population today is many times greater than it was 8000 years ago and that we are using technology that didn’t exist back then, I would expect our influence on the climate to be many times greater than it was 8000 years ago. I’m not sure I’m seeing this…
led to the stabilization of atmospheric CO2 concentrations at a level that made the world substantially warmer than it otherwise would be.
So, if one were to believe this paper (…yeah, right…), human CO2 emissions probably saved the planet from entering a new ice age – isn’t that great? Because: the general temperature trend during the last 8000 years has been a downward slope. If it would have been “substantially” colder without humans messing with forests, that downward slope would have been a lot steeper, and the “little ice age” could very well have turned into a real glacial phase.
Jimbo: Great collection of links :-D!
All life on Earth interacts with and influences the climate.
All geological functions, like tectonics and the weathering of rocks and erosion, interacts with and influences the climate.
How much longer will we be subjected to the Capt. Obvious level of climate science ‘discoveries’ that are used to sell global climate disruption?
It’s all the bacteria’s fault. From ABC, Australia:
http://www.abc.net.au/science/articles/2010/02/09/2814540.htm?topic=
“Finnish researchers have called for a revision of climate change estimates after their findings showed emissions from soil would contribute more to climate warming than previously thought.”
Scientists, it would seem, can prove anything catastrophic. And they wonder why we distrust them. http://www.bbc.co.uk/programmes/b00y4yql
The sad thing is, all this distrust will probably cause us to throw the baby with the bathwater. [trimmed by request]
This is what happens when scientists swallow the idea that co2 is climate control king. If it is the only influence that affects climate then we have to fit into historical climate somehow. Anyhow… Poor blighters.
Jimbo says:
January 24, 2011 at 7:50 am
Jimbo hit the nail on the head. It is no surprise that the preponderance of global warming research press releases is highly correlated to the huge increases in funding seen world-wide over the past ten years. When the money dries up (as it inevitably will), so will the press releases…
In particular, look for some MAJOR downsizing of climate funding in the US over the next two years…
This really is complete nonsense. This is proof that the current models are totally wrong, the fact you can use them to conjecture something so ridculous.
Jimbo says:
January 24, 2011 at 7:50 am
===================================
priceless Jimbo
They do have a small point about Man producing carbon in some quantities before some magic date in the 1850s as the transition to steam did not happen as with the click of a switch. One only has to look at the poorer parts of Asia to get an idea of the carbon output from fires and from the relatively primitive industrial power sources there, but I suspect their idea of reality is more imaginative than real. Reading accounts of Wellington’s campaigns in the Peninsula Wars reminds one of the human and animal numbers required to maintain just one foot soldier in the large armies on the march and in battle, which must also have produced more than a little carbon.
It might be an idea if one of these computer gamers got a job on an up-to-date mixed farming enterprise, then they would find out just how little (not how much) land is actually required now to sustain x numbers of humans. And they postulate that medieval man’s carbon use diminished after plague had swept through a population – who ever would have imagined that! Visiting Sienna, for example, and seeing the great religious building projects that were stopped dead in their tracks and left incomplete in the intervening centuries is a reminder of the effects of a sudden 50% depopulation by plague.
From the release: “‘Thanks to the reports of the early explorers, we know that the forests were less abundant on the American continent. Then the settlers gradually eliminated the indigenous population.’ Threatened with extinction, these populations effectively deserted the forested areas, which – by taking up the carbon in the atmosphere – in turn set off the legendary frosts of the 19th century.”
Am I reading this correctly and the authors are saying displacement of native american aboriginal populations caused the LIA..?
This study reads more like fictional narrative than scientific research. The entire argument of the paper—that changes in world population and extent of agricultural land use cause climate change because of their impact on carbon dioxide levels—is not supported by evidence. CO2 levels have been increasing the past 8000 years; however, the pre-historical temperature record dating back 8000 years shows long term cooling, not warming.