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3
- #1
zdas04
Mechanical
- Jun 25, 2002
- 10,274
I have been repeatedly accused of refusing to accept the basic "facts" of Anthropogenic Cimate Change (ACC nee AGW, nee Global Warming, nee Global cooling). I think we really need to define terms.
In the following I'm going to rely heavily on The Shattered Greenhouse: How Simple Physics Demolishes the "Greenhouse Effect". I've linked the article in for anyone who wants to check my interpretation of the story. It has an extensive bibliography at the end for further reading.
Greenhouse Effect
The basic idea of a greenhouse gas comes from Arrhenius' in 1896 representing (some say misrepresenting) the work of Fourier from 1827
This idea ignores the fact that in greenhouses, the glass acts to prevent the heated air from mixing with the ambient air outside the box (i.e., prevents mass transfer) and has nothing to do with different wave lengths of light. The ACC concept says that the heating is due to energy absorption and disregards the fact that hot gases rise and there is no physical barrier to how far they can rise.
The linked article ends with:
If the thermodynamic underpinning of the "Greenhouse Effect" is absolutely missing, ACC does not have a leg to stand on.
Carbon Dating
Much has been made about the "fact" that atmospheric CO[sub]2[/sub] must have come from geologically old sources because of the lack of Carbon-14 in the atmospheric CO[sub]2[/sub]. The idea of carbon dating is the result of very creative work in 1946 by Willard Libby at the University of Chicago. His concept is that Nitrogen-14 in the atmosphere is bombarded by solar radiation and that some proportion of the impacts will cause the stable nitrogen to lose a neutron and become radioactive Carbon-14 (radiocarbon). He further postulated that the number of collisions is relatively constant and that as animals breathed the C14 a portion of it would be absorbed into their systems and decay to Carbon 12 over time. This means that as long as the animal is breathing they will be ingesting C14. When the animal stops breathing they will stop ingesting C14 and the inventory of radiocarbon in their bodies will decay with a half life of 5730 years. So if you find a sample with 1/4 as much C14 as you expect then it is something like 11,460 years old. There are a large number of assumptions that go into this calculation, and many of them are invalid for any given biological sample, and the uncertainty in dating cam be millennia.
The big question is what sources of fuel have zero C14? Of course hydrocarbons that haven't been alive for 300 million years likely have zero C14. Same with CO[sub]2[/sub] from volcanoes. What about biological material that has been frozen under the permafrost since the last ice age (2.58 to 0.012 million years ago)? That stuff has been through a lot of half lives of C14. So if the climate is warming, and if the permafrost is retreating, then biological action on the newly thawed material would have zero C14. This means that C14-free CO[sub]2[/sub] in the atmosphere does not necessarily have to come from industrial activity.
Temperature Record
The temperature record is not just one thing.
[ul]
[li]Data from 2005 might be from digital instruments that self-report or from satellite surrogates.[/li]
[li]Data from 1970 likely comes from analog instruments manually recorded[/li]
[li]Data from 1900 likely comes from spotty coverage at universities and on ships.[/li]
[li]Data from 1800 comes from ice cores, sea floor samples, and tree ring analysis[/li]
[li]Data from thousands of years ago to about 1.5 million years ago come from ice cores[/li]
[li]Data older than that comes from analysis of the fossil record (i.e., what kind of plants were growing? how big were they?)[/li]
[/ul]
We have no way to directly measure temperature. We can't do it today. We couldn't do it 100,000 million years ago. We can measure the impact of a given temperature on a material with very good accuracy and repeatability and very low uncertainty. That mercury thermometer that your mum stuck up your bum didn't measure your temperature, it measured the thermal expansion of the mercury in a constrained channel. All temperature data is the result of an evaluation of the impact on something physical to a temperature change. To turn ice core data into temperatures the scientist melts the ice then boils the water in a tightly controlled space and evaluates the gasses that come out of the sample. A computer model is used to convert the mix of gases into a temperature. These models are very clever and quite involved. If you assume that CO[sub]2[/sub] forces temperature change, you get one set of temperature numbers. If you assume that changes in CO[sub]2[/sub] are a result of temperature change you get a very different set of temperature numbers. When people plot CO[sub]2[/sub] concentration on the same graph as "temperature" data they are being purposely misleading since everyone with the ability to run this calculation knows that they have selected "cause" or "effect" before they generated the temperature numbers and in spite of having different scales they are actually the same number.
The oldest data has a temporal uncertainty of no less than ±10,000 years. The Ice core data is probably ±200 years. Data from the 1800's is certainly ±1-2 years. Data from the early 1900's is around ±6 months. More contemporary data has a better temporal uncertainty.
Contemporary data is collected from thousands of weather stations and stored in a database. The database (actually there are several, each its own format) contains one record per station per time period. No indication that the data is anything but true and accurate like scientific data is supposed to be. It is anything but that. "Everyone" understands that temperature on a blacktop surface is higher than temperature on a grassy field. As urban populations have expanded to formerly rural spaces, many weather stations have shifted from rural to urban. If you look at the data for the station, there is a step change in the output. To be able to compare a station that is currently urban to data from when it was rural, requires some "adjustments". These adjustments are done destructively without even a flag in the database. Also many of the stations have been broken for months or years and just receive "estimates", without any explicit definition of the estimating technique.
Finally, the historical record can be modified. Luckily several "outsiders" made copies of the databases at various times. Comparing those copies to the "official" records indicates some distinct trends. Several warm periods from the past are no longer included in the historical record. Data from 2000, show the 1930's to have been as much as 5°F warmer than the current string of "warmest on record years". Many of those record-breaking years were warmer by less than 0.05°F when the contemporary records have an uncertainty of ±0.1°F, but "Warmest Year on Record" gets headlines.
Impact of Climate Change
The list of things that ACC is going to cause has been widely published. It includes wildfires, more hurricanes, more tornadoes, floods, droughts, more deserts, reduced biodiversity, rising sea level, etc. This list was generated by a group of grad students sitting around a table throwing out ideas. Things like "when it is hotter it feels like the desert, I bet deserts will grow". In fact the geological record shows that in general during a warm epoch there is additional moisture in the atmosphere and deserts shrink--this is happening today all over the world. The list of consequences is not part of the "science" of ACC, but the scientists involved have rarely spoken out against the list. The scientific theories of ACC talk about physical reactions, but they can't even predict clouds or rotating systems let alone wildfires.
Consensus
Before you say you "believe" in ACC remember:
[bold]David Simpson, PE[/bold]
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
In the following I'm going to rely heavily on The Shattered Greenhouse: How Simple Physics Demolishes the "Greenhouse Effect". I've linked the article in for anyone who wants to check my interpretation of the story. It has an extensive bibliography at the end for further reading.
Greenhouse Effect
The basic idea of a greenhouse gas comes from Arrhenius' in 1896 representing (some say misrepresenting) the work of Fourier from 1827
In other words, visible light can traverse the atmosphere more easily than infrared can traverse the atmosphere back into space. Fourier actually said nothing of the kind, but it has entered our collective culture that he did.Arrhenius (1896 said:
This idea ignores the fact that in greenhouses, the glass acts to prevent the heated air from mixing with the ambient air outside the box (i.e., prevents mass transfer) and has nothing to do with different wave lengths of light. The ACC concept says that the heating is due to energy absorption and disregards the fact that hot gases rise and there is no physical barrier to how far they can rise.
The linked article ends with:
Consulting Geologist said:
If the thermodynamic underpinning of the "Greenhouse Effect" is absolutely missing, ACC does not have a leg to stand on.
Carbon Dating
Much has been made about the "fact" that atmospheric CO[sub]2[/sub] must have come from geologically old sources because of the lack of Carbon-14 in the atmospheric CO[sub]2[/sub]. The idea of carbon dating is the result of very creative work in 1946 by Willard Libby at the University of Chicago. His concept is that Nitrogen-14 in the atmosphere is bombarded by solar radiation and that some proportion of the impacts will cause the stable nitrogen to lose a neutron and become radioactive Carbon-14 (radiocarbon). He further postulated that the number of collisions is relatively constant and that as animals breathed the C14 a portion of it would be absorbed into their systems and decay to Carbon 12 over time. This means that as long as the animal is breathing they will be ingesting C14. When the animal stops breathing they will stop ingesting C14 and the inventory of radiocarbon in their bodies will decay with a half life of 5730 years. So if you find a sample with 1/4 as much C14 as you expect then it is something like 11,460 years old. There are a large number of assumptions that go into this calculation, and many of them are invalid for any given biological sample, and the uncertainty in dating cam be millennia.
The big question is what sources of fuel have zero C14? Of course hydrocarbons that haven't been alive for 300 million years likely have zero C14. Same with CO[sub]2[/sub] from volcanoes. What about biological material that has been frozen under the permafrost since the last ice age (2.58 to 0.012 million years ago)? That stuff has been through a lot of half lives of C14. So if the climate is warming, and if the permafrost is retreating, then biological action on the newly thawed material would have zero C14. This means that C14-free CO[sub]2[/sub] in the atmosphere does not necessarily have to come from industrial activity.
Temperature Record
The temperature record is not just one thing.
[ul]
[li]Data from 2005 might be from digital instruments that self-report or from satellite surrogates.[/li]
[li]Data from 1970 likely comes from analog instruments manually recorded[/li]
[li]Data from 1900 likely comes from spotty coverage at universities and on ships.[/li]
[li]Data from 1800 comes from ice cores, sea floor samples, and tree ring analysis[/li]
[li]Data from thousands of years ago to about 1.5 million years ago come from ice cores[/li]
[li]Data older than that comes from analysis of the fossil record (i.e., what kind of plants were growing? how big were they?)[/li]
[/ul]
We have no way to directly measure temperature. We can't do it today. We couldn't do it 100,000 million years ago. We can measure the impact of a given temperature on a material with very good accuracy and repeatability and very low uncertainty. That mercury thermometer that your mum stuck up your bum didn't measure your temperature, it measured the thermal expansion of the mercury in a constrained channel. All temperature data is the result of an evaluation of the impact on something physical to a temperature change. To turn ice core data into temperatures the scientist melts the ice then boils the water in a tightly controlled space and evaluates the gasses that come out of the sample. A computer model is used to convert the mix of gases into a temperature. These models are very clever and quite involved. If you assume that CO[sub]2[/sub] forces temperature change, you get one set of temperature numbers. If you assume that changes in CO[sub]2[/sub] are a result of temperature change you get a very different set of temperature numbers. When people plot CO[sub]2[/sub] concentration on the same graph as "temperature" data they are being purposely misleading since everyone with the ability to run this calculation knows that they have selected "cause" or "effect" before they generated the temperature numbers and in spite of having different scales they are actually the same number.
The oldest data has a temporal uncertainty of no less than ±10,000 years. The Ice core data is probably ±200 years. Data from the 1800's is certainly ±1-2 years. Data from the early 1900's is around ±6 months. More contemporary data has a better temporal uncertainty.
Contemporary data is collected from thousands of weather stations and stored in a database. The database (actually there are several, each its own format) contains one record per station per time period. No indication that the data is anything but true and accurate like scientific data is supposed to be. It is anything but that. "Everyone" understands that temperature on a blacktop surface is higher than temperature on a grassy field. As urban populations have expanded to formerly rural spaces, many weather stations have shifted from rural to urban. If you look at the data for the station, there is a step change in the output. To be able to compare a station that is currently urban to data from when it was rural, requires some "adjustments". These adjustments are done destructively without even a flag in the database. Also many of the stations have been broken for months or years and just receive "estimates", without any explicit definition of the estimating technique.
Finally, the historical record can be modified. Luckily several "outsiders" made copies of the databases at various times. Comparing those copies to the "official" records indicates some distinct trends. Several warm periods from the past are no longer included in the historical record. Data from 2000, show the 1930's to have been as much as 5°F warmer than the current string of "warmest on record years". Many of those record-breaking years were warmer by less than 0.05°F when the contemporary records have an uncertainty of ±0.1°F, but "Warmest Year on Record" gets headlines.
Impact of Climate Change
The list of things that ACC is going to cause has been widely published. It includes wildfires, more hurricanes, more tornadoes, floods, droughts, more deserts, reduced biodiversity, rising sea level, etc. This list was generated by a group of grad students sitting around a table throwing out ideas. Things like "when it is hotter it feels like the desert, I bet deserts will grow". In fact the geological record shows that in general during a warm epoch there is additional moisture in the atmosphere and deserts shrink--this is happening today all over the world. The list of consequences is not part of the "science" of ACC, but the scientists involved have rarely spoken out against the list. The scientific theories of ACC talk about physical reactions, but they can't even predict clouds or rotating systems let alone wildfires.
Consensus
Before you say you "believe" in ACC remember:
For every Michael Mann there is a Judith Curry. For every Al Gore there is a Jim Imhoff (U.S. Senator from Oklahoma). For every David Suzuki there is a Lord Monkton. For every Bill Nye there is a Jack-in-the-Box Clown. For every IPCC report there are contributors who claim their statements were misrepresented. The 97% consensus was made up from whole cloth. Before this subject got so political and began having so much money thrown at it, there were frank and honest discussions among the scientific community and people of varying views could get published or get on the podium at conferences. Not today. There are a large number of scientists who have actually lost tenure for holding opinions that the ACC story does not hold up to scrutiny, and getting published with papers outside the mainstream is nearly impossible. Not the "science" of my youth.
[bold]David Simpson, PE[/bold]
MuleShoe Engineering
In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist
