What's the scientific evidence for climate change?

[What Would Jesus Do?]

I bet we could buy interior land in Australia cheap. Maybe run a scam selling bunker space there? We could get the libs and cons to buy into that for different reasons.

It's a brilliant place to have massive solar farms. But too inhospitable for human habitation.

Except . . . I suppose with all that solar you wouldn't have to worry about the cost of AC. Water, on the other hand....

I wonder what life is like on Tasmania. Australia has much easier immigration laws, I think. As long as you are of Anglo extraction.

 

[What Would Jesus Do?]

This is the sensationalism I've been talking about, folks. Right here.

How so?

 

[The Tradition]

How so?

"years of safety"

You can safely live anywhere you like. For years. Your children can inherit your place and live safely. For years. The ocean isn't going to rise up and swallow you like in that stupid global warming movie. There will be no sudden catastrophic loss of safety. It will be a very gradual process that can be easily mitigated and adopted to changing conditions. As a species, we're really good at that.

 

[Joes Place]

Once again you chose to fvcking outright lie instead of admitting that very big assumptions are being made.

From the very website of your holy grail...

What are the main limitations of the study?
The temperature reconstructions are based on inferences made from natural archives that store information about past climate (such as tree rings), but are not thermometers per se. Translating proxy evidence to past temperatures involves making important assumptions. For instance, we assume that the relation between temperature and the proxy record that existed during the instrumental period is the same as that which existed during pre-historic time.

Large uncertainties about past temperature variability remain, especially during the first millennium when only some regions are represented. In Africa, there are currently too few records to make a reliable continental-scale temperature reconstruction.

Some of the reconstructions focus on summer conditions and others on annual averages. The two can be somewhat different, although they are correlated in meteorological records from our regions.

How were uncertainties accounted for in the temperature reconstructions?
Measuring proxy values, placing them on a timescale, integrating records from unevenly distributed sites, and converting them to temperature all involve uncertainties. Each of the PAGES 2k Network groups used somewhat different approaches to estimate the uncertainty in the reconstructed temperature (as described in the Supplementary Information). The synthesis does not formally address these uncertainties, focusing instead primarily on the best (expected-value) estimates of temperature. In addition, some of the analyses circumvent most sources of uncertainty. For example, the site-level analysis of individual records assumes only that the proxies are sensitive to temperature.

Apparently, you missed these parts:

1. Global temperatures have been slowly DECLINING over the past 2 millennia
2. Global temperatures are AT LEAST 0.2°C HIGHER when the PAGES2K work was performed, as opposed to the temperatures only up to about 2003 or so, when the data was gathered for your 2006 reference. THAT information clearly puts recent warming ABOVE anything in the records to which you are referring. If you cannot understand that LATER publications, with MORE RECENT information are MORE RELEVANT than OLDER reference, then I cannot help you, other than to refer you to my post #88, above.

 

[naturalmwa]

It's a brilliant place to have massive solar farms. But too inhospitable for human habitation.

Except . . . I suppose with all that solar you wouldn't have to worry about the cost of AC. Water, on the other hand....

I wonder what life is like on Tasmania. Australia has much easier immigration laws, I think. As long as you are of Anglo extraction.

I watched a documentary on Tasmania. It gets cold and the devils don't spin around. Overall it was a disappointing documentary.

 

[What Would Jesus Do?]

What's it from?

I would imagine that the carbon emissions from a volcano are from burning carbon that was sequestered millions of years ago in the subduction zone of said volcano.

No?

What's what from?

Sorry if I missed some background here, but volcanoes are not a particularly significant source of carbon release into the atmosphere. So why are we having this conversation?

Nor does carbon make up a significant portion of the Earth's crust. And most of what little there is is bound in carbonate rocks. So while you might get a lot of carbon release if a volcano happened to become active below a coal or oil field, it's unlikely to be much of a concern.

A quick google suggests that volcanic activity contributes about 1% compared with human activity.

 

[The Tradition]

What's what from?

Sorry if I missed some background here, but volcanoes are not a particularly significant source of carbon release into the atmosphere. So why are we having this conversation?

Nor does carbon make up a significant portion of the Earth's crust. And most of what little there is is bound in carbonate rocks. So while you might get a lot of carbon release if a volcano happened to become active below a coal or oil field, it's unlikely to be much of a concern.

A quick google suggests that volcanic activity contributes about 1% compared with human activity.

A claim was made that we can tell one CO2 molecule from another based on isotopes. Supposedly, terrestrial carbon (i.e., manufactured by plant life) has a different isotope signature from sequestered carbon. So I asked, how do we tell the difference between carbon from burning fossil fuels from those emitted from volcanoes? What I got was more stuff about plants.

 

[What Would Jesus Do?]

I watched a documentary on Tasmania. It gets cold and the devils don't spin around. Overall it was a disappointing documentary.

How cold? Remember, things are warming, in general.

If not for Canada's ruinous and poisonous energy policies over the last decade or so, the interior of Canada might be a good place to consider. A few degrees of increase could make it like Iowa, a few more like Texas. Texas is too hot for me, but I'll probably be dead by then.

One other thought about Australia. If the ice caps and Greenland do melt, the interior of Australia may be an inland sea or a giant harbor open to the Pacific. But that could take a few hundred years.

 

[The Tradition]

How cold? Remember, things are warming, in general.

Yes, I'm sure it'll be just like The Bahamas in just a few short years.

 

[naturalmwa]

A claim was made that we can tell one CO2 molecule from another based on isotopes. Supposedly, terrestrial carbon (i.e., manufactured by plant life) has a different isotope signature from sequestered carbon. So I asked, how do we tell the difference between carbon from burning fossil fuels from those emitted from volcanoes? What I got was more stuff about plants.

I thought volcanos got their goo from way down deep, not near the surface. So there presumably would be little plant life in it.

 

[artradley]

That article doesn't say anything about volcanoes. It talks about plants.

What do volcanoes even have to do with this conversation?

 

[The Tradition]

I thought volcanos got their goo from way down deep, not near the surface. So there presumably would be little plant life in it.

So where does the carbon come from? And does it have a terrestrial carbon isotope signature, or a sequestered carbon isotope signature?

 

[What Would Jesus Do?]

A claim was made that we can tell one CO2 molecule from another based on isotopes. Supposedly, terrestrial carbon (i.e., manufactured by plant life) has a different isotope signature from sequestered carbon. So I asked, how do we tell the difference between carbon from burning fossil fuels from those emitted from volcanoes? What I got was more stuff about plants.

Look up carbon 14 dating. That will explain better.

The idea is that living things incorporate carbon into them as they grow and stop incorporating carbon when they die.

A certain percentage of free carbon that gets incorporated into living critters is carbon 14, which decays at a known rate. So after something dies, the ratio of C14 to the rest of the carbon slowly declines. By measuring that ratio, we can ascertain how old the thing was when it died.

Carbonate rocks were either never living or derived from free carbon so long ago that the C14 measure ranges from nonexistent to so low that it's now longer a significant measure of age.

So, except for the volcano that erupts under a coal or field, it's easy to tell the CO2 from volcanoes from that coming from driving cars and whatnot because of the hugely different C14 ratios.

 

[The Tradition]

What do volcanoes even have to do with this conversation?

~sigh~

I guess it's too hard to go back and read the discussion?

 

[The Tradition]

Look up carbon 14 dating. That will explain better.

The idea is that living things incorporate carbon into them as they grow and stop incorporating carbon when they die.

A certain percentage of free carbon that gets incorporated into living critters is carbon 14, which decays at a known rate. So after something dies, the ratio of C14 to the rest of the carbon slowly declines. By measuring that ratio, we can ascertain how old the thing was when it died.

Carbonate rocks were either never living or derived from free carbon so long ago that the C14 measure ranges from nonexistent to so low that it's now longer a significant measure of age.

So, except for the volcano that erupts under a coal or field, it's easy to tell the CO2 from volcanoes from that coming from driving cars and whatnot because of the hugely different C14 ratios.

So why wouldn't there be any sequestered carbon near a volcano that's being burned and emitted? And how do we tell the difference?

 

[tarheelbybirth]

So why wouldn't there be any sequestered carbon near a volcano that's being burned and emitted? And how do we tell the difference?

Now you're just trolling. Nobody could be this obtuse.

 

[The Tradition]

Now you're just trolling. Nobody could be this obtuse.

That really didn't answer the question. Guess that means you don't have an answer and you were talking out your ass from the beginning.

 

[naturalmwa]

That really didn't answer the question. Guess that means you don't have an answer and you were talking out your ass from the beginning.

I took it to mean the question was already answered. When the volcano explodes and the trees on the side of the mountain burn, thats carbon looks different than the carbon that came from the center of the earth.

 

[Joes Place]

Look up carbon 14 dating. That will explain better.

The idea is that living things incorporate carbon into them as they grow and stop incorporating carbon when they die.

A certain percentage of free carbon that gets incorporated into living critters is carbon 14, which decays at a known rate. So after something dies, the ratio of C14 to the rest of the carbon slowly declines. By measuring that ratio, we can ascertain how old the thing was when it died.

Carbonate rocks were either never living or derived from free carbon so long ago that the C14 measure ranges from nonexistent to so low that it's now longer a significant measure of age.

So, except for the volcano that erupts under a coal or field, it's easy to tell the CO2 from volcanoes from that coming from driving cars and whatnot because of the hugely different C14 ratios.

It's actually not due to C14 'decay' rates (which would have been impacted by nuclear tests since the 1950s)

It's actually C13/C12 ratios; plants actually 'discriminate' against C13 during growth (see referenced PDF below):

Plant photosynthesis discriminates against 13C. In other words, plant carbon tends to have less 13C than the CO2 from which it is formed (Fig. 1). This discrimination provides a tool for interpreting changes in 13C of atmospheric CO2​

So if rising CO2 levels were from plant matter (e.g. fossil fuels MADE FROM ancient plants), then the C13/C12 ratio should be dropping. And that is what is happening.

Note that the RED line is tracking in 'negative' percentages (the scale is inverted). This allows the plot to overlay and track with the overall emissions estimate - you can see the similar 'break points' in the curves this way. The scales are different, because the amount of carbon emitted thru fossil fuel burning is small relative to the overall amount of CO2 in the atmosphere, but it is not insignificant.

If burning fossil fuels were NOT the source of the carbon/CO2, then there would be (and SHOULD BE) NO CHANGE in the C13/C12 ratio. This is how we are absolutely certain the CO2 is coming from our activities, burning previously sequestered ancient plant matter.

The paper on this is here:
http://www.bgc.mpg.de/service/iso_gas_lab/publications/PG_WB_IJMS.pdf

Note that this is NOT published in a 'climate' journal, it is published in a Mass Spectrometry journal, because that is the nature of the work performed - physical chemistry/mass spec. And, yes, I have experience in mass spec among other assaying techniques.

 

[Joes Place]

I took it to mean the question was already answered. When the volcano explodes and the trees on the side of the mountain burn, thats carbon looks different than the carbon that came from the center of the earth.

Basically correct - carbon coming from 'rocks' or other non-photosynthesis processes has a different C13/C12 ratio signature. Carbon from plants, living or ancient stuff buried for millions of years, has a lower C13/C12 ratio than from geologic processes.

 

[Joes Place]

Once again you chose to fvcking outright lie instead of admitting that very big assumptions are being made.

From the very website of your holy grail...

What are the main limitations of the study?
The temperature reconstructions are based on inferences made from natural archives that store information about past climate (such as tree rings), but are not thermometers per se. Translating proxy evidence to past temperatures involves making important assumptions. For instance, we assume that the relation between temperature and the proxy record that existed during the instrumental period is the same as that which existed during pre-historic time.

Large uncertainties about past temperature variability remain, especially during the first millennium when only some regions are represented. In Africa, there are currently too few records to make a reliable continental-scale temperature reconstruction.

Some of the reconstructions focus on summer conditions and others on annual averages. The two can be somewhat different, although they are correlated in meteorological records from our regions.

How were uncertainties accounted for in the temperature reconstructions?
Measuring proxy values, placing them on a timescale, integrating records from unevenly distributed sites, and converting them to temperature all involve uncertainties. Each of the PAGES 2k Network groups used somewhat different approaches to estimate the uncertainty in the reconstructed temperature (as described in the Supplementary Information). The synthesis does not formally address these uncertainties, focusing instead primarily on the best (expected-value) estimates of temperature. In addition, some of the analyses circumvent most sources of uncertainty. For example, the site-level analysis of individual records assumes only that the proxies are sensitive to temperature.

I'll try to keep this simple for you:

When they are comparing paleoclimate to today, we don't use 'year-by-year' resolutions, we use decadal resolutions which iron out the wrinkles.

YOUR paper was from ~2006; I believe they used 'reference data' for current temperatures up to the mid/late 1990s.
MY link is from ~2014, so they have another decade OR MORE of data for comparing temperatures to the 2000 year dataset. (NOTE that 'reference' papers like the one you linked are NOT original research, they are SUMMARIES of OLDER papers)

Look at this graph and see what global temperatures have done in that past 10+ years (using decadal smoothing):

So, 10-15 years ago (circa: the origin of the data referenced in your 2006 paper) the average temperature MAY HAVE OVERLAPPED the error bars from the prior peaks in the 2000 year record; TODAY those temperatures are EXCEEDING the error bars, as we are AT LEAST 0.2°C WARMER: Now, we CAN see the difference.

Again, this is why we look at the more RECENT data and rely less on OLDER comparisons which are based on OUTDATED datasets.

 

[artradley]

~sigh~

I guess it's too hard to go back and read the discussion?

I have read the thread -- I don't see where you explain why you brought up volcanoes.

 

[Joes Place]

So where does the carbon come from? And does it have a terrestrial carbon isotope signature, or a sequestered carbon isotope signature?

Put simply, CO2 that comes from a plant-based source (including oil, coal, natural gas) has a DIFFERENT isotopic ratio (C13/C12) than CO2 generated by geologic processes. The difference is CO2 arising from photosynthetic mechanisms (e.g. plant material, or from animals that ate the plant material)

 

[tarheelbybirth]

That really didn't answer the question. Guess that means you don't have an answer and you were talking out your ass from the beginning.

Do you understand that CO2 can arise inorganically (meaning without life) through geologic processes? The Earth produces CO2 with no input from living things. Do you know that? If yes, then you have already answered your own question. If not, then your ignorance is profound and you should refrain from entering an opinion lest you reveal that state.

The CO2 released in volcanic eruptions - from the volcano's crater and vents...the eruption - is inorganically derived. It's CO2 produced through geologic processes. A burning tree on the side of the volcano WOULD produce organically derived CO2 but the ratio of inorganic to organic would be beyond enormous.The organic CO2 would be a blip compared to the inorganic CO2 released directly through the eruption.

The CO2 coming from the volcano itself is inorganic in origin and presents a different isotopic signature compared to organic CO2. The CO2 responsible for the rise in atmospheric CO2 shows an ORGANIC origin.

Do you understand now? To put one more nail in this coffin, if it were volcanoes that were responsible for the rise in CO2, we should have a documented corresponding rise in volcanism over the time period. We don't.

 

[Joes Place]

Do you understand that CO2 can arise inorganically (meaning without life) through geologic processes? The Earth produces CO2 with no input from living things. Do you know that? If yes, then you have already answered your own question. If not, then your ignorance is profound and you should refrain from entering an opinion lest you reveal that state.

The CO2 released in volcanic eruptions - from the volcano's crater and vents...the eruption - is inorganically derived. It's CO2 produced through geologic processes. A burning tree on the side of the volcano WOULD produce organically derived CO2 but the ratio of inorganic to organic would be beyond enormous.The organic CO2 would be a blip compared to the inorganic CO2 released directly through the eruption.

The CO2 coming from the volcano itself is inorganic in origin and presents a different isotopic signature compared to organic CO2. The CO2 responsible for the rise in atmospheric CO2 shows an ORGANIC origin.

Do you understand now? To put one more nail in this coffin, if it were volcanoes that were responsible for the rise in CO2, we should have a documented corresponding rise in volcanism over the time period. We don't.

Plus, manmade emissions of CO2 exceed volcanic emissions (for ALL volcanoes, terrestrial AND sub-marine), by a factor of about 130:1. EVEN IF volcanic emissions were of the 'same' C13/C12 ratio, that ratio would have been in equilibrium millennia ago and still mainly constant today - only if volcanic activity increased by at least two orders of magnitude could it explain the C13/C12 ratio change.

Because volcanic emissions primarily have a different C13/C12 ratio than plant matter, it's even easier to see what's going on, and volcanic CO2 emissions are mostly negligible, both overall and on C13/C12 ratios.

 

[Titanhawk2]

I don't know much about climate change and I'm just starting to read about it. If scientists agree almost unanimously that it's real, and the Republican electorate and leadership believe it's not real, then I know the scientists are right

So, what is the scientific evidence for climate change?

I know I'm late to the party here, but the question should be evidence for man made CC, and proof man can change it in the future. CC does happen, we just adapt

 

[coloradonoles]

I'll try to keep this simple for you:

When they are comparing paleoclimate to today, we don't use 'year-by-year' resolutions, we use decadal resolutions which iron out the wrinkles.

YOUR paper was from ~2006; I believe they used 'reference data' for current temperatures up to the mid/late 1990s.
MY link is from ~2014, so they have another decade OR MORE of data for comparing temperatures to the 2000 year dataset. (NOTE that 'reference' papers like the one you linked are NOT original research, they are SUMMARIES of OLDER papers)

Look at this graph and see what global temperatures have done in that past 10+ years (using decadal smoothing):

So, 10-15 years ago (circa: the origin of the data referenced in your 2006 paper) the average temperature MAY HAVE OVERLAPPED the error bars from the prior peaks in the 2000 year record; TODAY those temperatures are EXCEEDING the error bars, as we are AT LEAST 0.2°C WARMER: Now, we CAN see the difference.

Again, this is why we look at the more RECENT data and rely less on OLDER comparisons which are based on OUTDATED datasets.

Again you are moving the goalposts, I have conceded that in the last 50 or so years we have been experiencing a warming trend and possibly all the way back to the 1880s and the 136 years that I have mentioned several times... my problem has always been with the historical data, which you call proxy data. It is the best way we have to try a reconstruct the past but it is lacking in the amounts of data, the regions the sparse data covers and the overall margin of error for each method used.

You laughed at me for referencing a 2006 paper and I SPECIFICALLY asked you if the sparse data coverage and uncertainties associated with that data has changed...

So... you are "LMAO" about a link I made from 2006, all the while touting a paper from 2013 that references 2 from from the very paper I posted?!?!?!? The same proxy studies referenced in mine!!!!!! Unbelieveable...

• Very little confidence can be assigned to statements concerning the hemispheric mean or global mean surface temperature prior to about A.D. 900 because of sparse data coverage and because the uncertainties associated with proxy data and the methods used to analyze and combine them are larger than during more recent time periods.

Has any of that changed???

Yep. Because they used a LOT more sources and data to develop their conclusions. That's why it was dated AFTER your source (and probably utilizes about a decade's worth of additional info).

Same reason why we don't try to use Newton's Principia to undermine Einstein's relativity theory.....not sure why this is so difficult for you.

You said "Yep", which is CLEARLY not this case. And you continue to reference that you need to babysit me... smh.

So fast forward to 2014 and the PAGES 2K study/paper , if I understand correctly they broke up into regions and looked at the proxy data again using new methods...

How were the temperature reconstructions created?
Each regional group identified the currently available proxy climate records that they found best suited for reconstructing temperature variability within their region. Most of the regional groups used either a scaling approach to adjust the mean and variance of a composite of the proxy records to an instrumental target (based on data from thermometers during the 20th century), or a regression-based technique to extract a common signal from the proxy data. The mathematical procedures that were used are presented in the 54-page Supplementary Information that was published along with the article.

They weren't exactly going out and taking new tree cores and pollen samples and recreating a new proxy record, they were simply looking at the same raw data (in the archives) everyone else had used in the past and looked at it from a different perspective. They regurgitated the same numbers after massaging it to match a pre-conceived result...

How were uncertainties accounted for in the temperature reconstructions?
Measuring proxy values, placing them on a timescale, integrating records from unevenly distributed sites, and converting them to temperature all involve uncertainties. Each of the PAGES 2k Network groups used somewhat different approaches to estimate the uncertainty in the reconstructed temperature (as described in the Supplementary Information). The synthesis does not formally address these uncertainties, focusing instead primarily on the best (expected-value) estimates of temperature. In addition, some of the analyses circumvent most sources of uncertainty. For example, the site-level analysis of individual records assumes only that the proxies are sensitive to temperature.

No matter how many autopsies you do on a body, you still have the same body. The limited and incomplete data doesn't change.

So you come on here and tout "GLOBAL WARMING" when in fact you think its warming (hell, I'm not even saying its not) and you have very little idea if it has warmed any in the last 2000 years but have decided that based on 50 years of data you can predict the demise of all mankind.

It is laughable that any credible scientist could take such a small sample size and infer anything with a greater confidence of "Most likely". But your side has made it out as if it is written in stone and even the possibility of other outcomes is impossible and is shouted down as a "Denier". Politics and the media has taken up the cause and as long as the money is coming in the fund further research you don't say a peep about them constantly over-stating facts and making wild and bold predictions "in the name of science".

You see, I too have an undergraduate degree in Mathematics (from Florida State 1993) and while my career path has taken me quite a distance from the world of math, I am still pretty conversant in the terms and methods of its use. Admittedly I don't remember the term "error bars" specifically, I would imagine that is very similar to what we used to call the margin of error signified by +/-, but perhaps in the 25 years since I got my degree terms have changed or my memory has faded.

 

[NoleSoup4U]

The climate here in Sarasota, FL changes pretty much every day.

 

[What Would Jesus Do?]

"years of safety"

You can safely live anywhere you like. For years. Your children can inherit your place and live safely. For years. The ocean isn't going to rise up and swallow you like in that stupid global warming movie. There will be no sudden catastrophic loss of safety. It will be a very gradual process that can be easily mitigated and adopted to changing conditions. As a species, we're really good at that.

You really don't know what you are talking about.

Look at what's happening in Europe with probably no more than a million or so refugees needing places. What do you think the world will look like when hundreds of millions are being displaced?

 

[coloradonoles]

You really don't know what you are talking about.

Look at what's happening in Europe with probably no more than a million or so refugees needing places. What do you think the world will look like when hundreds of millions are being displaced?

You mean finally realizing that 3000 years of living in a desert under an oppressive government and none of that is going to change is an ancillary benefit of GW?

 

[Joes Place]

Again you are moving the goalposts, I have conceded that in the last 50 or so years we have been experiencing a warming trend and possibly all the way back to the 1880s and the 136 years that I have mentioned several times... my problem has always been with the historical data, which you call proxy data. It is the best way we have to try a reconstruct the past but it is lacking in the amounts of data, the regions the sparse data covers and the overall margin of error for each method used.

You laughed at me for referencing a 2006 paper and I SPECIFICALLY asked you if the sparse data coverage and uncertainties associated with that data has changed...


No matter how many autopsies you do on a body, you still have the same body. The limited and incomplete data doesn't change.

I did not SAY it had 'changed'. I said there were MORE datasets, which altered the analysis. It means that the error ranges on the proxy and historical data changed and most likely shrunk down a bit. That is what I've tried to explain when mentioning 'error bars' numerous times. And another poster I believe posted that you do not understand what 'error bars' are. You clearly do not. 'Sparse data' means error bars are larger. That's it. And that is precisely how those proxy data are represented in historical data sets.

So you come on here and tout "GLOBAL WARMING" when in fact you think its warming (hell, I'm not even saying its not) and you have very little idea if it has warmed any in the last 2000 years but have decided that based on 50 years of data you can predict the demise of all mankind.

It is laughable that any credible scientist could take such a small sample size and infer anything with a greater confidence of "Most likely". But your side has made it out as if it is written in stone and even the possibility of other outcomes is impossible and is shouted down as a "Denier". Politics and the media has taken up the cause and as long as the money is coming in the fund further research you don't say a peep about them constantly over-stating facts and making wild and bold predictions "in the name of science".

We have very GOOD information that the climate has been VERY stable over the past 10,000 years, since the last glaciation period and recession.

That you are unable to understand the error bars on datasets is really your problem, not that of the scientists using them.

Furthermore, as I've stated NUMEROUS times in this thread, the global temperature CANNOT just change randomly by 0.5°C or more without SOME forcing altering the thermal balance. You don't just randomly shoot out guesses as to what the 'forcing' is, you use SCIENCE and PHYSICS to limit the guesses to plausible possibilities, THEN you use the math to TEST those possibilities. And as I've stated over and over again, there are ZERO options right now that can explain the 1.0 to 1.5°C increase during the industrial age. I've asked 'deniers' numerous times what their 'guess' or 'hypothesis' is for the forcing, and NONE can provide anything. Unsurprising, because NEITHER CAN ANY OF THE SCIENTISTS if they limit the guesses to 'natural' forcings, including those they KNOW were responsible for paleo-climate change.

Just because you can do a little math doesn't make you a scientist. And if you're too far from college to remember what error bars are on a dataset, you should probably just listen to the people who understand them....

 

[naturalmwa]

You mean finally realizing that 3000 years of living in a desert under an oppressive government and none of that is going to change is an ancillary benefit of GW?

Not from my perspective.

 

[Joes Place]

They weren't exactly going out and taking new tree cores and pollen samples and recreating a new proxy record, they were simply looking at the same raw data (in the archives) everyone else had used in the past and looked at it from a different perspective. They regurgitated the same numbers after massaging it to match a pre-conceived result...

Wrong. Your 'opinion', perhaps. But since you don't really understand science or the scientific method (or error bars), I'm sure it's all 'Greek' to you...

No matter how many autopsies you do on a body, you still have the same body. The limited and incomplete data doesn't change.

As I have TRIED to explain to you at LEAST twice now: Global temperatures are AT LEAST +0.2°C HIGHER when PAGES2K did their comparison with regard to when YOUR referenced subject matter was written.

That is a LARGE shift. And when that shift moves the current warming ABOVE what the previous error bars was, they can say with CONFIDENCE it is warmer than the past 2000 years. 1971-1999 may NOT have been warmer than the past 2000 years; but 1995-2015 absolutely HAS been. A 5th grader can understand this concept.

 

[tarheelbybirth]

You see, I too have an undergraduate degree in Mathematics (from Florida State 1993) and while my career path has taken me quite a distance from the world of math, I am still pretty conversant in the terms and methods of its use. Admittedly I don't remember the term "error bars" specifically, I would imagine that is very similar to what we used to call the margin of error signified by +/-, but perhaps in the 25 years since I got my degree terms have changed or my memory has faded.

Then you should have understood that that "tenth of a degree C" you were so exercised about came with a "margin of error".

I am willing to concede that the global temperature has been rising in the last 100 years, to some extent due to human causes.... if you will consent that science has NO idea what the GLOBAL temperature was from 1600-1700. Not regional, not Northern Hemisphere, but the entire Earth's temperature to the accuracy of a tenth of a degree C.

You understood that...right? And if you did...why did you make such a dumb comment? Perplexing.

 

[naturalmwa]

Could someone explain "error bars" so I could be one of the cool kids please?

 

[tarheelbybirth]

Could someone explain "error bars" so I could be one of the cool kids please?

They define the level of uncertainty with the numbers in a data set. With temps, they get larger as you go back in time due to the greater uncertainty.

Welcome to the cool kids club. There's a certificate and a decoder ring.

 

[naturalmwa]

They define the level of uncertainty with the numbers in a data set. With temps, they get larger as you go back in time due to the greater uncertainty.

Welcome to the cool kids club. There's a certificate and a decoder ring.

 

[coloradonoles]

Wrong. Your 'opinion', perhaps. But since you don't really understand science or the scientific method (or error bars), I'm sure it's all 'Greek' to you...



As I have TRIED to explain to you at LEAST twice now: Global temperatures are AT LEAST +0.2°C HIGHER when PAGES2K did their comparison with regard to when YOUR referenced subject matter was written.

That is a LARGE shift. And when that shift moves the current warming ABOVE what the previous error bars was, they can say with CONFIDENCE it is warmer than the past 2000 years. 1971-1999 may NOT have been warmer than the past 2000 years; but 1995-2015 absolutely HAS been. A 5th grader can understand this concept.

 

[coloradonoles]

Then you should have understood that that "tenth of a degree C" you were so exercised about came with a "margin of error".

I am willing to concede that the global temperature has been rising in the last 100 years, to some extent due to human causes.... if you will consent that science has NO idea what the GLOBAL temperature was from 1600-1700. Not regional, not Northern Hemisphere, but the entire Earth's temperature to the accuracy of a tenth of a degree C.

You understood that...right? And if you did...why did you make such a dumb comment? Perplexing.

Huh? That is EXACTLY the point... the margin of error for any such temperature range (1600-1700 in this case) would likely be over 1*C... therefore how can we say that the global temperature has risen .6*C (or whatever the number is) in the last 500 years when we don't even know what the starting number is!

I have stated in this thread that the proxy data for Africa is so bad that a climate reconstruction isn't even possible... how can we possibly infer anything with respect to GLOBAL temperatures with such a huge subset of data nonexistent?

The whole GW/CC mantra is presented in a way that implies that the temperature is rising uniformly around the globe, i.e. its getting 1*C hotter everywhere on Earth, and that simply isn't the case.

 

[coloradonoles]

Could someone explain "error bars" so I could be one of the cool kids please?

It's basically a graphic depiction of the standard deviation.

The same thing can be accomplished by giving a +/- at the bottom.