Because history was my first intellectual love, and I read it for pleasure, the aspect of ‘climate change’ that interests me most is the history of climate. In terms of measurable matters, we are trapped between two stories: first, the very modern, the last century or a little more, when there were thermometers, and the distant past, where we use the techniques of palaeontology. But where thermometers can give us daily, even hourly, data to play with, palaeontology deals in years, and is better with even larger chunks of time.

The outcome is a lot of uncertainty, with one side saying that what is happening is unprecedented, and the other saying that it’s all happened before. My sceptical bent prefers the second, but my agnostic spirit wants to see better data. Tony Brown, an English student of climate, has done some amazing work using historical sources to try to pinpoint what was happening in climate (in Europe mostly) over the last thousand years. You can read his papers here, and he writes very well, too.

Jennifer Marohasy, whom I mentioned in my last post, has a most interesting essay on her website on historical accounts of extreme heat in Australia. Surprise, surprise — the really hot times seem to have been at the end of the 19th century and the beginning of the 20th. Not only that, death rates from extreme heat (bush fires, for the most part) have plummeted. More people died in Australia from extreme heat events in 1896 than in any other year, with 450 dead nationally. The second worst year was 2009 with 432 dead, followed by 1939 with 420. Considering these numbers in terms of total population, then we have a decline from about 13 dead per 100,000 in 1896, to 6 per 100,000 in 1939, to just 2 per 100,000 in 2009.

Now to my third example of climate history, this time from Canada, where Dr Tim Ball runs a lively website. He is a former Professor of Geography, and an essay of his appeared in WUWT the other day. It is mostly about how climate is always changing, but what struck me was a map and a story connected with it. Ball writes

In my climate research I found a map drawn in 1772 by fur trader and self-taught biologist Samuel Hearne. He followed the tree line (he called it the “woods edge”) from Churchill on the southwest coast of Hudson Bay to the Coppermine River on the Arctic coast and plotted it on a map. It’s a very distinct boundary, as I know from flying over this region for five years…


Hearne, whose observations on Arctic Fox are still considered among the best, made a remarkable, astute, comment in his journal.

“I have observed, during my several journeys in those parts that all the way to the North of Seal River the edge of the wood is faced with old withered stumps, and trees which have been flown (sic) down by the wind. They are mostly of the sort which is called here Juniper, but were seldom of any considerable size. Those blasted trees are found in some parts to extend to the distance of twenty miles from the living woods, and detached patches of them are further off; which is proof that the cold has been increasing in those parts for some ages. Indeed, some of the older Northern Indians have assured me that they have heard their fathers and grandfathers say, they remembered the greatest part of those places where the trees are now blasted and dead, in a flourishing state. (Hearne, 1772, p.138).

Hearne’s observations fit the climate record. The tree line advanced during the warmth of the Medieval Warm Period (MWP) then retreated in the cooling to the nadir of the Little Ice Age (LIA). Hearne describes this with his comment that this is “proof that the cold has been increasing in those parts for some ages”. It has warmed since Hearne’s time and the tree line has advanced with a pattern of movement appropriate for the general circulation of the region.

Comparing the “woods edge” (Figure 2) as Hearne drew it in 1772, with the tree line determined 200 years later by Rowe (1972) and Elliot-Fisk (1983), the amount of movement is significant. In the west/east portion from Great Slave Lake to Churchill on Hudson Bay, movement was up to 300 km. This means it moved more than one kilometer per year. Even if it is only half that, it is a remarkable rate of adjustment in one of the harshest growing environments anywhere.

What a story! Earlier than Hearne there had been extensive forest to the north of his line, during a warmer period. After him, things got progressively warmer again until today the new tree line is a great distance to the north from where it was in the early 18th century. It is these reconstructions that appeal to me as a quondam historian, and they tell me that we can all too easily assume that what is happening now has no counterpart in human history.

But that is to assume that only what we can measure precisely is of any significance. Human society, in a form we would recognise, is 10,000 years old, and there has been considerable climate change in that time. We know it from records, like those Tony Brown has collected, and by inference from abandoned reservoirs in the Sahara Desert.

And we need more of this history and pre-history. It is a corrective to the frequent cry that ‘nothing like this has been seen in human history’.

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  • Peter Kemmis says:

    So was Hearne’s treeline along the furthest extension of ‘old and withered stumps’, or the living trees? From his account this is not clear, but perhaps the distinction is not material.

    In my view not sufficient attention is given to the human historical record. Very recently my wife and I had the opportunity to visit the ancient site of Ephesus, which in the days of St Paul was accessible inland some five kilometers along a river serving as a narrow reach of the Aegean Sea. The story we were given was that silting had subsequently closed access to the old port. Hmm, I thought, that’s an awful lot of silt. What other examples of silting occurred in that region? What about tectonic movements (nearby there’s a striking example of shearing in a hillside from an earthquake), and what about sea levels back then? At what altitude above sea level is the old port today? But these are inconvenient questions. It’s easier just to say it’s all down to silt. Maybe it is, and perhaps I have the problem of not readily trusting what I’m told, especially in such matters of changing climates.

    Why the great deserts where civilisations once flourished? Do we blame Milankovitch cycles for all that, with the associated changes in wind and rainfall patterns? Or other long cycles, such as the Eddy cycle? Silly to just say we over-grazed fragile ecosystems. A land flowing with milk and honey? As a child I never understood that one – it seemed pretty torrid country to me when I was in Sunday School. Ah well, back to my bolt-hole now . . .

    • Gus says:

      “We” did not overgraze anything. “We” weren’t present at the time. It always bugs me somewhat when people say “we” in this context, as if attempting to lay blame on me, amongst others, for whatever may have transpired at some time, somewhere.

      Desertification of Sahara… yes, it’s the Milankovitch cycle in action. It happened pretty quickly and in historic times, about 3500BC and is attributed to the change in the Earth’s orbit, see Claussen et al, Geophysical Research Letters, July 15, 1999, doi:10.1029/1999GL900494.

      • Mike O'Ceirin says:

        Good god man don’t you realise it is all our fault? We must pay penance for our sins and appease the great green God Gaia for we are sinners all and must grovel in our guilt.

    • Mike O'Ceirin says:

      Another instance of what you speak of is in the UK. I have noted that quite often the tv show “Time Team” will talk about the area they are in was a port in Roman Times. The sea in the present day is maybe 50 Km away but on the show there is not much interest in why, silt often is mentioned and that is a lot of silt. I have read that the UK is tilling so maybe that is it?

    • dlb says:

      I have seen the same in Italy. In antiquity Pisa was a port city only 4km inland from the coast. Today the port is in Livorno, now 10km downstream of Pisa.

  • Gus says:

    The Köppen climate classification is based exactly on this: he looked at plants that grew naturally in various places and drew boundaries of various climate regions from that. It’s a clever system and a clever approach, because plants naturally occurring in various places are the best markers of climate. The Köppen’s scheme has been improved over the years somewhat, but the basic idea is still there and not changed much since Köppen’s days (1884) at all. You can see a map of the world with Köppen-Geiger (this is how it is called nowadays) climate boundaries drawn on it in a Wikipedia article on this topic. I happen to live very close to the boundary between Dwa (humid continental) and Cfa (humid subtropical). This gives us hot and humid summers normally, but also cold and snowy winters.

    The Köppen-Geiger zone boundaries are best established by looking at older plants, plants that take… decades, even centuries to grow, like trees. Why? Because weather fluctuates from year to year, from decade to decade. Plants being opportunistic, move north (where I live) in warmer times, then a cold spell comes every now and then (like this year, when winter temperatures in my area dropped to -30C) and kills the little adventurists. So, nature retreats in response. Thus the boundary seems to fluctuate all the time, but not if it’s drawn from the presence of old trees. The ones that are well established are also invulnerable to weather vagaries. They can take the cold, the heat, the drought, the flood–whatever nature throws at them in a given location.

    From this we infer that it takes decades, even hundreds of years of observations to *define* climate for a given area. The old trees that grow around do exactly that. They are around for decades, or hundreds of years, and by their very presence and survival they tell us what climate in a given area is.

    The idea that you can tell that “climate is changing” on the basis of mere 30 years of observations is, frankly, fallacious. A century to me looks like about a minimum time span that is needed to just define a temporary climate in a given location. Then as you compare it with a previous century, you can, possibly, identify climate drift, if any.

    • Mike O'Ceirin says:

      As I understand it the climate in Australia a hundred years ago really is not much different to now. The Federation drought around 1900 was much the same as other more recent droughts. I thought much more than a hundred years would be necessary for a confirmed climate change.

      • Gus says:

        A century will give you one point and an error bar around it. If you want two points on the graph, you need two centuries: each will produce a point and an error bar. For a meaningful curve you need 10 points with error bars, that is, a millennium. Then only you can make pronouncements about “climate change.” Perhaps it would be OK to generate a point for each 50, perhaps even 30 years this way, so that you could study climate fluctuations on multidecadal scale. Anything on a shorter time scale is just weather, not climate.

        It is ironic that in all this discussion on “climate change,” the very notion of “climate” is so ill-defined. But then this is what warm-mongers want, isn’t it? This is why they dropped the term “global warming” to replace it with “climate change.” But as there is neither any observable warming (there hasn’t been any in more than 17 years now) nor is there any observable “climate change,” because climate does not change on such a short time scale, they are now talking about “climate disruption.” It’s just Orwellian Newspeak. All of it.

  • Mike O'Ceirin says:

    Thanks Don for this in particular the links to Tony Brown. I became skeptical about the Climate alarm when I watched a movie about Tuvalu it promoted the idea that we criminals in the developed world were flooding it by our life style. It was not honest for various reasons so I did some research and found their problem was population not sea level rise. In fact the relative sea level had fallen during the previous fifty years. I thought well if we are wrecking our planet what was it like in times past. I found Lamb and read much of his work plus someone else maybe Fagen. I found that really extreme severe weather is common in the not too distant past and that seeing a human footprint is difficult if not impossible.

    These days I think climate alarmism is a vehicle for other agendas. In the main it is about a religious zeal to save Gaia from the ravages of humanity. All promoted remedies for “Climate Change” if adopted would reduce human populations drastically. They are all misanthropic and that is the point. If it quacks like a duck it is a duck so history to Green is not important being the enemy of civilization is.

    • Gus says:

      I think, you’ll find that the story is more sinister. It’s not just the gangs of marching brain-dead eco-fascists. There is big money and big political influence behind it. The US Senate Committee on Environment & Public Works has just issued a minority report on “The Chain of Environmental Command,” in which it details how what it calls a Billionaire’s Club impacts the work of the Government working around the democratic institutions of the Congress. You can download the report from

      Also see the Forbes article about it at

      The key points of the report are:

      • The “Billionaire’s Club,” an exclusive group of wealthy individuals, directs the far-left environmental movement. The members of this elite liberal club funnel their fortunes through private foundations to execute their personal political agenda, which is centered around restricting the use of fossil fuels in the United States.

      • Public charities attempt to provide the maximum amount of control to their donors through fiscal sponsorships, which are a legally suspect innovation unique to the left, whereby the charity essentially sells its nonprofit status to a group for a fee.

      • Public charity activist groups discussed in this report propagate the false notion that they are independent, citizen-funded groups working altruistically. In reality, they work in tandem with wealthy donors to maximize the value of the donors’ tax deductible donations and leverage their combined resources to influence elections and policy outcomes, with a focus on the EPA.

      • Environmental Grantmakers Association (EGA) is a place where wealthy donors meet and coordinate the distribution of grants to advance the environmental movement. It is a secretive organization, refusing to disclose their membership list to Congress.

      • The Obama Administration has installed an audacious green-revolving door among senior officials at EPA, which has become a valuable asset for the environmental movement and its wealthy donors.

      • Former environmentalists working at EPA funnel government money through grants to their former employers and colleagues.

      • Under President Obama, EPA has given more than $27 million in taxpayer-funded grants to major environmental groups. Notably, the Natural Resources Defense Council and Environmental Defense Fund – two key activists groups with significant ties to senior EPA officials – have collected more than $1 million in funding each.

      • EPA also gives grants to lesser-known groups. For example, the Louisiana Bucket Brigade received hundreds of thousands of grants under former Administrator Lisa Jackson despite challenges by state regulators over the use of such grants.

      • In New York and Colorado, a pseudo grassroots effort to attack hydraulic fracturing has germinated from massive amounts of funding by the NY-based Park Foundation, as well as CA-based Schmidt Family Foundation and Tides Foundation.

      • Bold Nebraska is another example of faux grassroots where a purportedly local organization is, in fact, an arm of the Billionaire’s Club. It is a shield for wealthy and distant non-Nebraskan interests who seek to advance a political agenda without drawing attention to the fact that they have little connection to the state.

      • The circumstances surrounding the flow of money from 501(c)(3) and 501(c)(4) groups, and the likelihood of lax oversight, raises questions as to whether 501(c)(3) nonprofit foundations and charities are indirectly funding political activities.

      • 501(c)(4) Green Tech Action Fund receives millions of dollars from green 501(c)(3) organizations, then distributes the funds to other 501(c)(4) groups that donate to political campaigns.

      • The Billionaire’s Club knowingly collaborates with questionable offshore funders to maximize support for the far-left environmental movement.

  • dlb says:

    6000 years ago the sea level off eastern Australia was 1 – 2 metres higher than present. Sea temperatures were also higher and coral flourished in places such as Moreton Bay. This may have something to do with the Milankovitch cycles or maybe it is a climatic / oceanic cycle that is not yet understood. One thing for sure is that it was not caused by CO2. So why do we call today’s climate and sea-level unprecedented when the precedent is there a mere 6000 years ago.

    Another thing that amuses me is the concern about the Great Barrier Reef. When the aboriginals reached Australia there was no GBR, where it is today was high and dry and many kilometers inland.

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