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Big Bad Voodoo

Warmer temperatures 1000 and 2000 years ago

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http://wattsupwiththat.com/2012/10/18/yet-another-paper-demonstrates-warmer-temperatures-1000-years-ago-and-even-2000-years-ago/

Should I post climate change in conspiracy in future?

Now another paper, by Esper et al published in the Journal of Global and Planetary Change, shows that not only was the summers of the MWP equal or greater than our current warmth, but that the summers of the Roman Warm Period of 2000 years ago were significantly warmer than today.

This persistent climate signal allowed an estimation of temperature variability throughout the Common Era, revealing warmth during Roman and Medieval times were larger in extent and longer in duration than 20th century conditions.

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There is even more scientific research that say that climate change was not man made then opposite. I think that climate change thread should be in conspiracy sub forum.

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http://wattsupwithth...2000-years-ago/

Should I post climate change in conspiracy in future?

Now another paper, by Esper et al published in the Journal of Global and Planetary Change, shows that not only was the summers of the MWP equal or greater than our current warmth, but that the summers of the Roman Warm Period of 2000 years ago were significantly warmer than today.

This persistent climate signal allowed an estimation of temperature variability throughout the Common Era, revealing warmth during Roman and Medieval times were larger in extent and longer in duration than 20th century conditions.

Thought One: The paper Watts is refering to considers only the Northern Hemisphere. It's not GLOBAL - so it's about NORTHERN WARMING and not GLOBAL warming.

Doug

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http://wattsupwithth...2000-years-ago/

Should I post climate change in conspiracy in future?

Now another paper, by Esper et al published in the Journal of Global and Planetary Change, shows that not only was the summers of the MWP equal or greater than our current warmth, but that the summers of the Roman Warm Period of 2000 years ago were significantly warmer than today.

This persistent climate signal allowed an estimation of temperature variability throughout the Common Era, revealing warmth during Roman and Medieval times were larger in extent and longer in duration than 20th century conditions.

Thought Two: Chriantiansen and Ljungqvist compared temperatures of the Medieval Warm Period and Roman Warm Period with an 1880-1960 reference period. The current temperature excursion started in 1976. The standard baseline is 1951-1980. They weren't comparing these warm periods to the modern temperature regime.

You should read these things before you post them. Watts is being deliberately misleading, to put it politely.

Doug

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http://wattsupwithth...2000-years-ago/

Should I post climate change in conspiracy in future?

Now another paper, by Esper et al published in the Journal of Global and Planetary Change, shows that not only was the summers of the MWP equal or greater than our current warmth, but that the summers of the Roman Warm Period of 2000 years ago were significantly warmer than today.

This persistent climate signal allowed an estimation of temperature variability throughout the Common Era, revealing warmth during Roman and Medieval times were larger in extent and longer in duration than 20th century conditions.

Thought Three: According to Christiansen and Ljungqvist, the Medieval Warm Period was 0.6 degrees hotter than "today," meaning the 1880-1960 average. During their baseline period, the world was -0.181 degrees colder than the 1951-1980 average. For the Medieval Warm Period, you add their 0.6 degrees to the -0.181 degrees and find that the Medieval Warm Period was +0.419 degrees warmer than the 1951-1980 baseline.

But: the 1981-2010 average was +0.364 degrees warmer than the 1951-1980 baseline, meaning the MWP was +0.055 degrees warmber than the 30 years from 1981 to 2010.

And: the twenty years from 1991 to 2011 was +0.445 warmer than the 1951-1980 standard baseline. Meaning 1991 to 2011 was +0.257 degrees warmer than the Medieval Warm Period.

How about the last eleven years - the time when Little Fish says it didn't get any warmer? Those years were 0.548 degrees warmer than the baseline, or 0.129 degrees warmer than the Medieval Warm Period.

Chistiansen and Ljungqvist's data ends in 1960. The modern temperature excursion, what is usually meant by the term "Global Warming," began in 1976. Using that study to refute global warming is comparing apples and ornages: a kindergarten mistake.

If you read these things before you parrot them, you won't look like such a fool.

Doug

Edited by Doug1o29
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It should be a crime that somebody rapes virgin white paper to write a "study" to demonstrate that the temperatures during the Roman and Medieval warm periods were higher than in 1969.

Edited by questionmark

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Now another paper, by Esper et al published in the Journal of Global and Planetary Change, shows that not only was the summers of the MWP equal or greater than our current warmth, but that the summers of the Roman Warm Period of 2000 years ago were significantly warmer than today.

I haven't looked up this particular paper, but as chance would have it, I was working on Esper's Mount Magazine dataset when I decided to check UM.

Esper's Mount Magazine dataset runs from 1861 to 1968. It would be useless for comparing earlier temps to the modern period because it ends eight years before the modern temperature excursion began. This is a common problem with proxy datasets. Many of the ones we have are decades out-of-date. The chronology must be calibrated with the climate record before meaningful estimates can be made, but when you only have 80 years of data to calibrate, that is a little hard to do. And the Mount Magazine weather station only began operations in the 1950s, so there is less than 20 years of data to calibrate it.

The shortage of more-recent chronologies is the reason you see papers ending in the 1960s or 1980s.

This persistent climate signal allowed an estimation of temperature variability throughout the Common Era, revealing warmth during Roman and Medieval times were larger in extent and longer in duration than 20th century conditions.

Above I showed why this is not entirely true. The twentieth century saw the largest century rise in temps since the Ice Age. If your records don't go all the way to the end of it, you can't really make extrapolations like this. I know Jan Esper from dendro conferences and ecological conferences and I don't think this statement accurately parahprases his thoughts. But I'll be glad to double-check if anybody wants me to.

Should I post climate change in conspiracy in future?

No. You should post denialist claptrap there.

Doug

P.S.: Right on Watts' page it says that this study was of Scots pine in Sweden and Finland. That Sweden and Finland were warmer during the MWP and RWP is not exactly news. Watts is cherry-picking his studies. Again, you need to read these things before you post them.

Doug

P.P.S.: Check page 4. Dendrochronology does not record winter temperatures, for the most-part, because trees are dormant then and unable to respond (Shortleaf pine do respond to hard freezes, bending stress caused by storms and late-winter cold snaps, but they don't provide a continuous, or even averaged, temperature record for the winter months.). The chart that Watts shows is GROWING SEASON ONLY.

So what do we have? A study that covers only the warmer months in Sweden and Finland (One study site was in Norway.). Again, this is not a global study; it does not reflect global or winter conditions.

Doug

Edited by Doug1o29

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Thought One: The paper Watts is refering to considers only the Northern Hemisphere. It's not GLOBAL - so it's about NORTHERN WARMING and not GLOBAL warming.

Doug

Northen warming then-Okay so in north there were warmer times then recent.

Lets see south pole.

Now there's more ice at South Pole than ever

http://www.unexplained-mysteries.com/forum/index.php?showtopic=235803

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Now there's more ice at South Pole than ever

That's pack ice. Not the same as glacial ice. The pack ice proportion is miniscule compared to the total mass of Antarctic ice. And the ups and downs we're seeing are fluctuations about a mean - random variation. The question is: what is the mean doing?

I don't have any ice core studies from Antarctica, so I can't tell you what's been happening down there. Because of the circumpolar current, Antarctica is pretty much a place unto itself.

Pack ice in the Arctic is another issue because it controls the earth's albedo in the north, which in turn controls sea surface temperature. Once the Arctic pack ice is substantially gone, the Arctic Ocean will warm faster. What we need to worry about is the rate and location of deep water formation. If the evaporation basin stays in the North Atlantic where it is now, we should be OK. But if we get a new basin in the Arctic Ocean, we could then see very rapid warming of the oceans. Don't know which way it's going to go, but it seems that we're going to find out.

Doug

Edited by Doug1o29

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Thought One: The paper Watts is refering to considers only the Northern Hemisphere. It's not GLOBAL - so it's about NORTHERN WARMING and not GLOBAL warming.

Doug

michael mann's hokey schtick was limited to northern hemispehre temperatures, doesn't stop the alarmist flagellants and the IPCC from putting it on their sandwich boards though.

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michael mann's hokey schtick was limited to northern hemispehre temperatures, doesn't stop the alarmist flagellants and the IPCC from putting it on their sandwich boards though.

How true. Political partisans of both stripes can't seem to keep the science and the hype apart.

While we're talking about Mann: to this day, no research article debunking his work has been submitted to a scientific journal. What's out there is blogs and unsubstantiated accusations. That says pretty definitely that their purpose is political, not scientific.

Doug

Edited by Doug1o29

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Double Post

Edited by Doug1o29

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While we're talking about Mann: to this day, no research article debunking his work has been submitted to a scientific journal. What's out there is blogs and unsubstantiated accusations. That says pretty definitely that their purpose is political, not scientific.

not true.

http://www.uoguelph.ca/~rmckitri/research/MM03.pdf

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<skip>

The Doggerland area at that time, 8100 BP is more promising than go look for evidence in the larger area it occupied during the LGM. During the LGM Doggerland was nothing but a large frozen tundra, but around 8100 BP it was a good place to live; some say the avarage temperature was a few degrees Celsius higher than in present Britain. It had large forests, lakes, marshes, meadows, rivers and hills (but not as high as the Dogger Hills).

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I stand corrected. Energy and Environment is a peer-reviewed journal (I think.).

Somewhere I remember reading a critique of this exact paper. I'll have to see if I can find it. I recall that one of their complaints was that there was "missing data" in the analysis. I found the "missing data" on a COFECHA printout. The elevation of a site in Quebec was missing. As this does not enter into the calculations at all, it is a little hard to understand what they are complaining about.

Another complaint was that Mann et al. had infilled some data in one of the chronologies. ARSTAN does this automatically, a feature I find very annoying. At any rate, the error introduced by this method is miniscule (The "missing" values are generated by the program from other values obtained by direct measurement; the error is tiny and allows other other parts of the chronology to be used when otherwise they couldn't be. The technique is frowned upon by statistical purists and (I think.) unnecessary if you have an adequate database to begin with, which the Quebec chronology was. This to me looks like an unintentional oversight: the program infilled the data automatically and Mann et. al did not catch it.

Also, I seem to recall an article that McKittrick claimed had undergone months of peer review and yet was shot down only weeks after publication because of technical errors.

I'll see what I can find.

Doug

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Thought Three: According to Christiansen and Ljungqvist, the Medieval Warm Period was 0.6 degrees hotter than "today," meaning the 1880-1960 average. During their baseline period, the world was -0.181 degrees colder than the 1951-1980 average. For the Medieval Warm Period, you add their 0.6 degrees to the -0.181 degrees and find that the Medieval Warm Period was +0.419 degrees warmer than the 1951-1980 baseline.

But: the 1981-2010 average was +0.364 degrees warmer than the 1951-1980 baseline, meaning the MWP was +0.055 degrees warmber than the 30 years from 1981 to 2010.

And: the twenty years from 1991 to 2011 was +0.445 warmer than the 1951-1980 standard baseline. Meaning 1991 to 2011 was +0.257 degrees warmer than the Medieval Warm Period.

How about the last eleven years - the time when Little Fish says it didn't get any warmer? Those years were 0.548 degrees warmer than the baseline, or 0.129 degrees warmer than the Medieval Warm Period.

Chistiansen and Ljungqvist's data ends in 1960. The modern temperature excursion, what is usually meant by the term "Global Warming," began in 1976. Using that study to refute global warming is comparing apples and ornages: a kindergarten mistake.

Chistiansen and Ljungqvist show the graph of their proxy reconstructions with the instrumental record overlayed (green-line), so together the chart shows 20th century warming in context to the MWP (~1000AD), so you can see that 20th century warming is not dissimilar to what occurred ~900-1000AD in terms of both magnitude and rate of change, this is important because it puts to bed the myth that 20th century warming is unprecedented in both magnitude and rate of change and further discredits mann's hokey schtick IPCC flagship graph.

christiansen-2000-year-temp-reconstruction-cf-fig-5.gif

If you read these things before you parrot them, you won't look like such a fool.
The poster "The L" doesn't look like a fool. the citation given in the OP is an important paper.

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I guess they had thermometers,wind gauges,weather balloons,and written weather reports between 1000/2000 yrs ago ?

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The poster "The L" doesn't look like a fool. the citation given in the OP is an important paper.

Thanks LittleFish on support.

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I guess they had thermometers,wind gauges,weather balloons,and written weather reports between 1000/2000 yrs ago ?

You don't really need those. What you need is sediments that are that old. By its contents you can reconstruct with 80% confidence any medium temperature at the time.

Edit, your problems start when you try to compare them with the medium of 1969 and then claim that it was warmer 1000 years ago:

02globalmean_warming.gif

between 1969 and 2000 we have a confirmed increase of almost 1 degree (Source)

A typical case of cherry picking data to demonstrate whatever you want to.

But we are making progress, they are already admitting that it is getting warmer. Five years ago that, according to certain "scientist" did not happen either.

Edited by questionmark

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You don't really need those. What you need is sediments that are that old. By its contents you can reconstruct with 80% confidence any medium temperature at the time.
if you believe what you say here then you should accept the reconstruction as displayed below, note that only good proxies were used that respond well to temperature, proxies like tree rings which do not respond well to temperature were not used.

christiansen-2000-year-temp-reconstruction-cf-fig-5.gif

Edit, your problems start when you try to compare them with the medium of 1969 and then claim that it was warmer 1000 years ago:
how can it be a problem when the same thing happened 1000 years ago. see chart above.
02globalmean_warming.gif

between 1969 and 2000 we have a confirmed increase of almost 1 degree (Source)

look at your own graph, it doesn't say that at all.
A typical case of cherry picking data to demonstrate whatever you want to.
isn't that what you did by focusing on only the data from 1969. furthermore why does your graph omit the last 12 years of data? cherry picking perhaps? why should we rule out a 1000 year natural solar-ocean cycle.
But we are making progress, they are already admitting that it is getting warmer. Five years ago that, according to certain "scientist" did not happen either.
I know of nobody who has claimed that, who are you talking about? Edited by Little Fish

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if you believe what you say here then you should accept the reconstruction as displayed below, note that only good proxies were used that respond well to temperature, proxies like tree rings which do not respond well to temperature were not used.

christiansen-2000-year-temp-reconstruction-cf-fig-5.gif

how can it be a problem when the same thing happened 1000 years ago. see chart above.

look at your own graph, it doesn't say that at all.

isn't that what you did by focusing on only the data from 1969. furthermore why does your graph omit the last 12 years of data? cherry picking perhaps? why should we rule out a 1000 year natural solar-ocean cycle.

I know of nobody who has claimed that, who are you talking about?

I will not have a problem with that graph as soon as I see the data, as the medieval "spike" there does not jive with anything I know.

And I know my own graph does not say that, but as it ends in 2000 it can hardly reflect the additional .2 degrees warming since then, 0.6 + 0.2 = 0.8, which according to me is almost one degree.

And you mean to tell me that the Oregon petition never happened?

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I will not have a problem with that graph as soon as I see the data
its linked at the top of the link in the original post.

http://wattsupwiththat.com/2012/10/17/new-paper-confirms-the-climate-was-warmer-1000-years-ago/

http://www.clim-past.net/8/765/2012/cp-8-765-2012.pdf

as the medieval "spike" there does not jive with anything I know.

if you look at all the MWP studies from different regions, it overwhelmingly jives with the published science. you can check these studies at the MWP project at http://www.co2science.org/data/mwp/mwpp.php what is different about this new study is that it analyses dozens of robust proxies across different regions, and confirms what we already knew for 50 years. it was only michael mann's graph and the ipcc that turned it all upside down in 1998 and 1999, and that graph has since been shown to be artifact of incorrect statistics and unreliable proxies.

And I know my own graph does not say that, but as it ends in 2000 it can hardly reflect the additional .2 degrees warming since then, 0.6 + 0.2 = 0.8, which according to me is almost one degree.
you said "between 1969 and 2000 we have a confirmed increase of almost 1 degree" which is not true, and there has been no global warming for the last 16 years, if you disagree then you are at odds with the UK met office and phil jones and Hadley CRU.
And you mean to tell me that the Oregon petition never happened?

yes it happened, this is what is said:

"We urge the United States government to reject the global warming agreement that was written in Kyoto, Japan in December, 1997, and any other similar proposals. The proposed limits on greenhouse gases would harm the environment, hinder the advance of science and technology, and damage the health and welfare of mankind. There is no convincing scientific evidence that human release of carbon dioxide, methane, or other greenhouse gasses is causing or will, in the foreseeable future, cause catastrophic heating of the Earth's atmosphere and disruption of the Earth's climate. Moreover, there is substantial scientific evidence that increases in atmospheric carbon dioxide produce many beneficial effects upon the natural plant and animal environments of the Earth."

that position is something i would currently agree with.

so where does it say in the above that "it is not getting warmer?"

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its linked at the top of the link in the original post.

http://wattsupwithth...1000-years-ago/

http://www.clim-past...-8-765-2012.pdf

if you look at all the MWP studies from different regions, it overwhelmingly jives with the published science. you can check these studies at the MWP project at http://www.co2scienc...ta/mwp/mwpp.php what is different about this new study is that it analyses dozens of robust proxies across different regions, and confirms what we already knew for 50 years. it was only michael mann's graph and the ipcc that turned it all upside down in 1998 and 1999, and that graph has since been shown to be artifact of incorrect statistics and unreliable proxies.

you said "between 1969 and 2000 we have a confirmed increase of almost 1 degree" which is not true, and there has been no global warming for the last 16 years, if you disagree then you are at odds with the UK met office and phil jones and Hadley CRU.

yes it happened, this is what is said:

"We urge the United States government to reject the global warming agreement that was written in Kyoto, Japan in December, 1997, and any other similar proposals. The proposed limits on greenhouse gases would harm the environment, hinder the advance of science and technology, and damage the health and welfare of mankind. There is no convincing scientific evidence that human release of carbon dioxide, methane, or other greenhouse gasses is causing or will, in the foreseeable future, cause catastrophic heating of the Earth's atmosphere and disruption of the Earth's climate. Moreover, there is substantial scientific evidence that increases in atmospheric carbon dioxide produce many beneficial effects upon the natural plant and animal environments of the Earth."

that position is something i would currently agree with.

so where does it say in the above that "it is not getting warmer?"

Your own graph the is at offs with the meteorological and whoever else office cause it shows very well a warming until 1998, but don't let that bother you.

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Your own graph the is at offs with the meteorological and whoever else office cause it shows very well a warming until 1998, but don't let that bother you.

the graph I showed is not at odds with the UK met office statement "there has been no global warming for the last 16 years". you did not respond to any of the points raised. i don't think your intention is for a meaningful discussion.

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the graph I showed is not at odds with the UK met office statement "there has been no global warming for the last 16 years". you did not respond to any of the points raised. i don't think your intention is for a meaningful discussion.

Oh but I don't have to, lets start with the Oregon paper, are you going to tell me that Peter Wegman had nothing to do with it? Or Robert Carter? They did deny global warming (though both have been clearly refuted and Wegman additionally been caught for plagiarism). But I guess, informed as you are you knew that.

Whatsupwiththat does not have any data at all and the study of Christiansen and Thoompson contains, under Conclusions (you know the part at the end) this paragraph:

The level of warmth during the peak

of the MWP in the second half of the 10th century,

equalling or slightly exceeding the mid-20th century

warming, is in agreement with the results from other

more recent large-scale multi-proxy temperature reconstructions

by Moberg et al. (2005), Mann et al. (2008,

2009), Ljungqvist (2010), and Ljungqvist et al. (2012).

So, nothing new there, we are exactly where we started and not at 1000 and 2000 years ago it was warmer.

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