46 replies to this topic

[the L]

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.

[the L]

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.

[Doug1o29]

the L, on 19 October 2012 - 11:11 AM, said:

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

[Doug1o29]

the L, on 19 October 2012 - 11:11 AM, said:

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

[Doug1o29]

the L, on 19 October 2012 - 11:11 AM, said:

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, 19 October 2012 - 01:22 PM.

[questionmark]

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, 19 October 2012 - 02:16 PM.

[Doug1o29]

the L, on 19 October 2012 - 11:11 AM, said:

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.

Quote

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.

Quote

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, 19 October 2012 - 02:43 PM.

[the L]

Doug1o29, on 19 October 2012 - 12:37 PM, said:

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.unexplain...howtopic=235803

[Doug1o29]

the L, on 19 October 2012 - 04:20 PM, said:

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, 19 October 2012 - 06:03 PM.

[Little Fish]

Doug1o29, on 19 October 2012 - 12:37 PM, said:

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.

[Doug1o29]

Little Fish, on 19 October 2012 - 06:04 PM, said:

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, 19 October 2012 - 06:39 PM.

[Doug1o29]

Double Post

Edited by Doug1o29, 19 October 2012 - 06:40 PM.

[Little Fish]

Doug1o29, on 19 October 2012 - 06:26 PM, said:

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....search/MM03.pdf

[Abramelin]

Abramelin, on 13 December 2009 - 02:52 PM, said:

<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).

[Doug1o29]

Little Fish, on 19 October 2012 - 07:36 PM, said:

not true.

http://www.uoguelph....search/MM03.pdf

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