Here is just one more indication that despite what some would like you to believe, the MWP was not a regional “non event”.
From a University of Arizona press release,
Giant Sequoias Yield Longest Fire History from Tree Rings
California’s western Sierra Nevada had more frequent fires between 800 and 1300 than at any time in the past 3,000 years, according to a new study led by Thomas W. Swetnam, director of UA’s Laboratory of Tree-Ring Research.
A 3,000-year record from 52 of the world’s oldest trees shows that California’s western Sierra Nevada was droughty and often fiery from 800 to 1300, according to a new study led by University of Arizona researchers.
Scientists reconstructed the 3,000-year history of fire by dating fire scars on ancient giant sequoia trees, Sequoiadendron giganteum, in the Giant Forest of Sequoia National Park. Individual giant sequoias can live more than 3,000 years.
“It’s the longest tree-ring fire history in the world, and it’s from this amazing place with these amazing trees.” said lead author Thomas W. Swetnam of the UA. “This is an epic collection of tree rings.”
The new research extends Swetnam’s previous tree-ring fire history for giant sequoias another 1,000 years into the past. In addition, he and his colleagues used tree-ring records from other species of trees to reconstruct the region’s past climate.
The scientists found the years from 800 to 1300, known as the Medieval Warm Period, had the most frequent fires in the 3,000 years studied. Other research has found that the period from 800 to 1300 was warm and dry.
“What’s not so well known about the Medieval Warm Period is how warm it was in the western U.S.,” Swetnam said. “This is one line of evidence that it was very fiery on the western slopes of the Sierra Nevada – and there’s a very strong relationship between drought and fire.”
Droughts are typically both warm and dry, he added.
Knowing how giant sequoia trees responded to a 500-year warm spell in the past is important because scientists predict that climate change will probably subject the trees to such a warm, dry environment again, said Swetnam, a UA professor of dendrochronology and director of UA’s Laboratory of Tree-Ring Research.
During the Medieval Warm Period extensive fires burned through parts of the Giant Forest at intervals of about 3 to 10 years, he said. Any individual tree was probably in a fire about every 10 to 15 years.
The team also compared charcoal deposits in boggy meadows within the groves to the tree-ring fire history. The chronology of charcoal deposits closely matches the tree-ring chronology of fire scars.
The health of the giant sequoia forests seems to require those frequent, low-intensity fires, Swetnam said. He added that as the climate warms, carefully reintroducing low-intensity fires at frequencies similar to those of the Medieval Warm Period may be crucial for the survival of those magnificent forests, such as those in Sequoia and Kings Canyon National Parks.
Since 1860, human activity has greatly reduced the extent of fires. He and his colleagues commend the National Park Service for its recent work reintroducing fire into the giant sequoia groves.
The team’s report, “Multi-Millennial Fire History of the Giant Forest, Sequoia National Park, California, USA,” was published in the electronic journal Fire Ecology in February. A complete list of authors and funding sources is at the bottom of this story.
To study tree rings, researchers generally take a pencil-sized core from a tree. The oldest rings are those closest to the center of the tree. However, ancient giant sequoias can have trunks that are 30 feet in diameter – far too big to be sampled using even the longest coring tools, which are only three feet long.
To gather samples from the Giant Forest trees, the researchers were allowed to collect cross-sections of downed logs and standing dead trees, he said. It turned out to be a gargantuan undertaking that required many people and many field seasons.
“We were sampling with the largest chain saws we could find – a chain-saw bar of seven feet,” he said. “We were hauling these slabs of wood two meters on a side as far as two kilometers to the road. We were using wheeled litters – the emergency rescue equipment for people – and put a couple hundred pounds on them.”
To develop a separate chronology for past fires, co-authors R. Scott Anderson and Douglas J. Hallett looked for charcoal in sediment cores taken from meadows within the sequoia groves.
“We can compare the charcoal and tree-ring fire records. It confirms that the charcoal is a good indicator of past fires,” Swetnam said.
Such charcoal-based fire histories can extend much further into the past than most tree-ring-based fire histories, he said. The charcoal history of fire in the giant sequoia groves extends back more than 8,000 years.
Increasingly, researchers all over the world are using charcoal to reconstruct fire histories, Swetnam said. Many scientists are analyzing the global record of charcoal to study relationships between climate, fire and the resulting addition of carbon dioxide to the atmosphere.
Swetnam’s co-authors are Christopher H. Baisan and Ramzi Touchan of the University of Arizona; Anthony C. Caprio of Sequoia and Kings Canyon National Parks in Three Rivers, Calif.; Peter M. Brown of the Rocky Mountain Tree-Ring Research and Colorado State University in Fort Collins; R. Scott Anderson of Northern Arizona University in Flagstaff; and Douglas J. Hallett of the University of Calgary in Alberta, Canada.
The National Park Service, the U.S. Geological Survey, Mountain Home Demonstration State Forest and Calaveras Big Trees State Park provided funding.
h/t to Dr. Leif Svalgaard
davidmhoffer, the indigenous peoples of North America definitely practiced agriculture and their “livestock” were the free herds of buffalo, deer, elk and others. The US constitution is greatly influenced by the Iroquois Constitution of the Five Nations/Iroquois Book of the Great Law. The land within the borders of the US were once populated by tens of millions of native peoples.
The invasion of Europeans upon the North and South American Continents resulted in genocide within any definition of the term.
You invoke Cortez as some sort of savior bringing horses yet he was the first among many destroyers of a vast and rich culture. Cortez the killer…the story of a homicidal maniac.
I think the native societies were more advanced than the likes of you davidmhoffer.
peace,
Tim
The research on indigenous peoples in the Americas is equal to the research of climate. All of the peoples in the Americas arrived during the last glaciation and spread since then. The tribes were small in most locations as there were few major advanced civilizations such as the Incas and Aztecs. Due to the northern areas just recovering from the glaciation the tribes were more hunter gatherers. A large portion of reduction blamed on Europeans was due to natural climate change that the natives were not able to adapt to. Of course it is always easier to blame others. Take into the number of Europeans that died due to not being able to adapt to living under conditions that existed in the Americas. This paper set about to make a claim while ignoring a more complete history they concentrated on the MWP to claim alarm due to drought caused by warming.
The only thing they showed was that the period was longer now and the climate varied just like now.
DesertYote (18:14:36) :
I would be interested in finding out what the evidence is for unusual drought conditions. Can anyone help educate me?
If you meant more generally what the evidence for medieval drought in the Sierras is, there is lots. Many lakes in the Sierras have sunken forests dating from Medieval times, so lake levels were a lot lower then across the Sierras. In the 90s, a tree was pulled from Fallen Leaf Lake, just off the south end of Lake Tahoe. The tree, dated to have grown from 1000-1200CE was rooted 120 feet below the present water level. So we know the lake was at least this low for at least this long.
Nearby, in the bed of the Truckee River, which now drains Lake Tahoe into the Nevada desert, there are the remains of a forest from the same period. So we know that Lake Tahoe was not high enough to drain during this period.
Also, tree lines, both total and species-specific, were 300-500 meters higher than at present during this period, which implies summer temperatures 3-4C higher than during the 20th century (and measured temperatures did not increase at all during the 20th century).
I do recall a recent article in Sciam about agriculture in the Amazon basin prior to 1492, and the conclusion was that the number people living in the Amazon basin was much larger than previously estimated.
Then there are the Anasazi, their cultural period runs from about 100 until 1600. Their culture was at its finest during 750 until 1300, after 1300 the culture declined until they disappeared around 1600. The height of the culture during the 750-1300 is clearly above the hunter/gatherer level.
And then there is the Mississippian culture from around 800 until 1500, a culture based upon intensive maize agriculture, advanced ceramics, trade networks, the did not have stone architecture, iron and bronze. But on a technical level they where not that far behind compared to the Europeans in that same period.
In the same time the period from 800 until 1300-1400 is know in Europe as the age of the cathedrals, the colonies on Greenland and such. It was a time when Europe started to stand up after the Dark Ages wich came after the fall of the Roman Empire that once covered a large part of Europe, Africa and the middle east. Why is that around 1350 the average lifespan of a European was only 17 years while a century before that it was still 39 years?
And then you can wonder why all those cultures went into decline around 1300-1500? And why the Europeans did not although the losses from famine and the black death where huge, and then i did not even mention that some pretty large scale conflicts where being fought amongst Europeans in that time-period.
The dryness of this period of the MWP in Cali suggests a strong and persistent “La Nina” phase and/or a prolonged negative PDO.
Cooler Pacific waters near the Cali shore mean less upward motion which means subsidence and very dry air.
But, as Rob has pointed out in another thread, the Giant Sequoias have evolved an ability to adapt to frequent fires [not to be confused with frequent fliers], and not only have they adapted to the fires….they learn how to thrive with it.
Lesson to self, and to species: We need to learn how to ADAPT to the changes in climate that come our way…no matter what they may be.
Chris
Norfolk, VA, USA
California (and the Sierras) are home to lightning storms, of the dry kind. This is to be found in old records, and is not anything new.
Dry lighting storms can cover large areas of the state. There’s no rain involved, a key requirement for the setup. Strikes can last 2-3 seconds, hitting white firs that normally don’t burn well, boil the pitch in the tree, which then explodes sending flaming goo all over the place.
savethesharks (23:06:16) :
Adaptation is the key to survival. AGW will remove that and the experiments they have planned for climate control means that the climate will be pegged one way or the other. They want to gamble with our very existence.
Mike D. has no idea what he is talking about. First of all the Giant Sequoias, as opposed to the coastal redwoods, grow at high altitudes. The General Sherman tree is at 6800′. While doubtless the Indians came to the area seasonally, they are snowed in about 5 months of the year. So there is no agriculture there or large herds of game to give the Indians a reason to start fires. The plains Indians regularly started fires both to clear land and to drive the buffalo herds. There was no advantage to starting fires in the high Sierras, and considerable danger.
I would just like to say – if you ever get the chance to visit a Sequoia grove, take it with both hands. These magnificent trees are in a truly beautiful setting, and inspire slack jawed amazement in even the most jaded ‘seen it all’ person. It is simply a majestic place and a wonderful feeling to stand in a quiet forest absolutely dwarfed by these giants.
Oh, and now that they have finished with the slabs, can I have one? Would make a killer table all polished up.
The MWP hump is portayed to occur around the same time as the Wolf minimum?
I wonder if there’s a co relationship with the Pacific Decadel Oscillation with the fires.
Wrt human or natural occurrence with the fires.. it doesn’t matter because regardless, a fire that can mark a tree with charcoal can only occur when the conditions are right, ie, dry and warm with some wind to carry it.
JC
There are crops that flourish under redwood trees: different kinds of berries, miner’s lettuce, sourgrass, various edible bulbs. I have read that when Europeans showed up here one could drive a wagon in any direction through the forests. They were open with little brush on the floor. Takes care of the poison oak!
Don’t read too much into that. The coastal redwood species are highly dependent upon the moisture from the coastal fog for their growth patterns. The high altitude redwoods like fog as well, but their environment in the high mountains resulted in a different type of growth response than the coastal redwoods.
Mike D — Are “historical acres under cultivation” in Europe and the Middle East a proxy for temperature? People are not machines. We are not robots impelled by climate. We are innovative, adaptive, and have always been culturally evolving.
Famine years in Europe have been crosslinked to climate conditions, yes. There are plenty of historical accounts and archaeology.
davidmhoffer — The range even a small tribe would have to hunt over to sustain themselves is large, and I just don’t buy 57 million being sustained with bows and arrows.
Bingo. Recently I’d read a book by historian David Starkey re Henry VIII and much of the information was radically different than other sources. Starkey explains this as being the result of much of the other sources being derived from Victorian era scholarship, which imparted its own spin, rather than a deep dive into the original known records and creating from scratch. One wonders about the actual level of scholarship claimed.
Meanwhile there are plenty of papers referenced at archaeological sites from scholars looking at e.g. neanderthal populations in Europe to 30,000 BCE and concluding anywhere from 10k to 100k max individuals could be sustained reliably. That was a forested continent.
Lastly, I don’t care what sort of Mann-o-matic statistical gyrations these twits want to beat the bad bad Euro-folk with, but surely 57 million souls in 1492 alone ought to have left a bit more of a mark; one could simply ask what became of the the millions of graves and other massive evidence that would support such a preposterous assertion. i.e. Extraordinary claims require extraordinary proof, after all.
Thus I ask for, nay, I DEMAND to see the actual physical proof; surely 57 million hunter gatherers ought to have left behind more arrowpoints etc than could be counted, etc. etc. etc.
And if American Indians did start forest fires why did they start more of them during the Medieval Warm Period, 800 to 1300, than at any other time?
Diabolical Mimicry
For those of you who think there was only a few hunter/gatherer tribes in North America in 1492, I strongly recommend a visit to Cahokia the next time you are in the St Louis area. Or to Chaco Canyon when in New Mexico.
And as for Central/south America, try el Mirador in Guatemala. The largest pyramid there is marginally larger than the Cheops pyramid.
Thanks Leif and Anthony for a thought provoking post.
The Medieval Climate Optimum (much more descriptive of the benefits of a few degrees extra warmth than MWP), is a very inconvenient truth for the IPCC CAGW cabal. The lengths they have gone to in order to hide this piece of historic climate data is astonishing, but as always, the truth will out.
Pity you can’t go back and get your money back from that professor. You were robbed!
The New World area is about 42,549,000 square kilometers. Some anthropologists estimate the pre-civilization paleolithic cultures had a population density of at least around some 0.1 persons per square kilometer. Such a population density would result in a population of at least some 4 million people in the New World living in pre-civilization hunter-gatherer groups. The population density then increases to at least 1 person per square kilometer as the hunter-gatherer cultures become more sophisticated and begin to develop agriculture and civilizations. The Mayan people are reported to have reached a population density of 1,295 to 1,813 people per square kilometer in the rural areas of the Mayan empire and 4,662 to 6,734 people per square kilometer in the Mayan cities.
The Bushmen of the Kalahari Desert achieved population densities in the desert environment of 1 to 1.5 people per square kilometer. The Aborigines of Australia reached about 0.1 persons per square kilometer. The Amerindian population density in the Amazon rain forest is about 1.5 to 2.5 people per square kilometer. The population of Papua-New Guinea ranges from 1 to 20 people per square kilometer from the lowlands to the highlands. To find any geography with a pre-industrial culture less than 0.1 people per square kilometer, you have to go to the Arctic or Antarctica, but even the High Arctic musters a native population density of 0.015 people per square kilometer.
In other words, any of the population densities for pre-industrial cultures known to exist in the Old World’s past and present and New World’s present imply minimum pre-Columbian New World populations numbering not less than about 4 million and probably numbering some multiple of 42 million square kilometers times 1 to many people per square kilometer.
I’ve got a giant Sequoia in my back garden, which was planted about 150 years ago. To get the small and iron-hard cones to open requires them to be charred in a bonfire for quite a time, and only then will the teeny-tiny seeds come out. They look like tiny flakes of rolled oats, and obviously have little or no value to squirrels who leave them well alone.
The soil is typical lowland heath; very very poor and acid, and guaranteed useless for any kind of agriculture. Out local common is a renowned example, having remained unexploited by agriculture since the last ice-age. But the Sequoia Giganteum ( aka Wellingtonia) really likes these conditions, and we have some great examples within a mile or so (one in a grove nearby was until fairly frequently in the Guiness book of records as the tallest tree in Britain)
The trunk bark of these trees oddly enough is very spongy and soft and is about five to ten times thicker that the Scots Pine bark. I guess it is very very hard to set fire to the trunk as this bark would act as as an intumescent protective layer. So I reckon the only way the trunk would get damaged is via a lightning strike or quite a big fire requiring a lot of dry undergrowth.
The tree produces a lot of biomass compared to an equivalent oak, and the whole of last year’s ‘needles’ which are quite heavy drop down evey year in one go over a coupe of weeks. If left, they form a mat which is inimical to other growth; and In a dry climate I could see that this store would provide the fuel for the occasional necessary reproductive fire.
The tree branches are curved and pendulous and tend to drop quite frequently when they are relatively very thin compared to the trunk thickness, and is commercially useless . The wood is very dry and shatters easily, and burns very badly and dangerously as it spits red hot embers like rifle-fire and is also useless as a fuel.
And from the privilege of living with and observing the habits of a Sequoiadendron Giganteum, I reckon that this species has zero practical value to man and beast; as these great defences probaly explain their longevity in their natural habitat.
And so I would give credence to the record of regular dry lightning fires found in the treering record.
As the Sovjet rewroted hitstory and even maps.
GISS is doing the same thing but with temperatures to fit thier political agenda.
So whats now needed to debunk the official lies of temperture history?
A new article has to be written by all honest experts in thier expertis of different
parts of the temperature history. We allready debunked the current records piece by piece.But there has to be an real effort to put it all together and even estimate the levels of uncertainy involved.They lied a hole world straight up in the face.The temperture records is the “book of revelation” to the AGW fraudster ideololgy.There is only lack of coordination to challenge the fraud of the establishment. The lack of serious peer review is the reason this has eveloped.
Thanks to everyone who is contributing with FACTS!
Now that is an untrue statement. The word, “genocide”, comes from “gens”, meaning the family or clan, and “cide”, meaning to kill. The dictionaries define the word to mean a deliberate attempt to kill an entire family of people on the basis of race, ethnicity, or comparable human affiliation. To “invade” means to enter with the purpose of plundering and conquering.
The European colonizations were in part invasions for the purpose of plundering and conquering, but they were also in part non-invading colonizations by invitation of the native inhabitants. These invitations to colonize were offered to bolster defenses against hostile native conquerors intent upon committing true genocide. Ultimately, the Euro-American colonists succeeded in stopping the genocides being committed by the Amerindian cultures against each other and also prevented a genocide of Amerindians by Euro-Americans. The result has been the deliberate preservation and restoration of the Amerindian populations to pre-Columbian levels, and not the deliberate extinction of those Amerindian populations indicative of a genocide.
Why does the ‘battle of the graphs’ show that old and outdated H.H. Lamb temperature graph for Europe, whereas the topic is on the incidence of bush fires in the west of the US (thus not even about temperature at all)?
Sorry, I know questions like this are too hard to be left uncensored.
This sounds like it was a dangerous, expensive, and difficult operation:
—————————–
It turned out to be a gargantuan undertaking that required many people and many field seasons.
“We were sampling with the largest chain saws we could find – a chain-saw bar of seven feet,”
“We were hauling these slabs of wood two meters on a side as far as two kilometers to the road. ”
“the emergency rescue equipment for people”
—————————–
Conpared to:
“To study tree rings, researchers generally take a pencil-sized core from a tree.”
Kind of makes Mann’s response to Steve McIntyre look a little feeble:
“Most reconstructions only extend through about 1980 because the vast majority of tree-ring, coral, and ice core records currently available in the public domain do not extend into the most recent decades. While paleoclimatologists are attempting to update many important proxy records to the present, this is a costly, and labor-intensive activity, often requiring expensive field campaigns that involve traveling with heavy equipment to difficult-to-reach locations (such as high-elevation or remote polar sites). For historical reasons, many of the important records were obtained in the 1970s and 1980s and have yet to be updated.”
http://climateaudit.org/2005/02/20/bring-the-proxies-up-to-date/
“Fires, by themselves are not an indication of drought. They could indicate an unusual amount of lightning”
Except that, as an expert in lightning, I can tell you that lightning intensity and frequency is dependent on climate and altitude. The higher up you are the more lightning you get and the warmer the climate you get the more lightning. Since we can assume there has been no great increase in altitude in California over 3000 years, we can say that any increase in lightning frequency was due to lightning.
However, it is estimated that about 90% of forest fires in the modern world are man-made. It should be pointed out that many of these man-made forest fires are, however, very much caused by modern man and would not have been the cause in ancient times. Nevertheless, we can perhaps assume that most of the forest fires in California over the last 3000 years were indeed anthropogenic. The question is why did the evidence of such anthropogenic fires rise during the medievel period? Why was that rise coincident with the MWP in Europe?
If you assume that the forest fires were linked to temperary climate change then there are two possibilities that become obvious. One is that the forest fires were a regular occurence but became more extensive due to the forest floor being tinder dry. The second is that the warmer climate caused the food supply to diminish resulting in more numerous failed attempts to deliberately clear the Sequoias to permit more farming.
I would submit that whilst this research cannot be considered proof that the MWP happened in the US as well as Europe, the sychronicity of these events with the MWP and the knowledge that these events could easily have been influenced by climate change in the US during the MWP strongly supports the theory that the MWP was a global phenomena.
“Why does the ‘battle of the graphs’ show that old and outdated H.H. Lamb temperature graph for Europe, whereas the topic is on the incidence of bush fires in the west of the US ”
Because the team-AGW claim that the MWP, if it happened at all, was limited to Europe, whilst this new research suggests that it occured in the US as well. It claims this on the basis that these “bush fires” are more frequent when you have warm dry weather (whatever the cause of the fire in the first place). Cold wet forests don’t catch fire very often, but warm dry forests do.