Reposted from The Air Vent
Disproving The Anthropogenic Global Warming (AGW) Problem
Leonard Weinstein, ScD
April 25, 2009
A theory has been proposed that human activity over about the last 150 years has caused a significant rise in Earth’s average temperature. The mechanism claimed is based on an increased greenhouse effect caused by anthropogenic increases in CO2 from burning of fossil fuels, deforestation, cement manufacture, and also from increases in CH4 from farm animals and other causes. The present versions of the theory also include a positive feedback effect due to the increased temperature causing an increase in water vapor, which amplifies the effect. The combined result are used to claim that unless the anthropogenic increases of CO2 are slowed down or even made to decrease, there will be a continuing rapid increase in global temperature, massive melting of ice caps, flooding, pestilence, etc.
In order to support a theory, specific predictions need to be made that are based on the claims of the theory, and the predictions then need to happen. While the occurrence of the predicted events is not proof positive of a theory, they increase the believability of the claims. However, if the predictions are not observed, this tends to indicate the theory is flawed or even wrong. Some predictions are absolute in nature. Einstein’s prediction of the bending of light by the Sun is such a case. It either would or would not bend, and this was considered a critical test of the validity of his theory of general relativity. It did bend the predicted amount, and supported his theory.
Many predictions however are less easily supported. For example weather forecasting often does a good job in the very short term but over increasing time does a poor job. This is due to the complexity of the numerous nonlinear components. This complexity has been described in chaos theory by what is called the butterfly effect. Any effect that depends on numerous factors, some of which are nonlinear in effect, is nearly impossible to use to make long-range predictions. However, for some reason, the present predictions of “Climate Change” are considered by the AGW supporters to be more reliable than even short-term weather forecasting. While some overall trends can be reasonably made based on looking at past historical trends, and some computational models can suggest some suggested trends due to specific forcing factors, nevertheless, the long term predicted result has not been shown to be valid. Like any respectable theory, specific predictions need to be made, and then shown to happen, before the AGW models can have any claim to reasonable validity.
The AGW computational models do make several specific predictions. Since the time scale for checking the result of the predictions is small, and since local weather can vary enough on the short time scale to confuse the longer time scale prediction, allowances for these shorter lasting events have to be made when examining predictions. Nevertheless, if the actual data results do not significantly support the theory, it must be reconsidered or even rejected as it stands.
The main predictions from the AGW models are:
-
The average Earth’s temperature will increase at a rate of 0.20C to 0.60C per decade at least to 2100, and will continue to climb after that if the CO2 continues to be produced by human activity at current predicted rates.
-
The increasing temperature will cause increased water evaporation, which is the cause for the positive feedback needed to reach the high temperatures.
-
The temperature at lower latitudes (especially tropical regions) will increase more in the lower Troposphere at moderate altitudes than near the surface.
-
The greatest near surface temperature increases will occur at the higher latitudes.
-
The increasing temperature at higher latitudes will cause significant Antarctic and Greenland ice melt. These combined with ocean expansion due to warming will cause significant ocean rise and flooding.
-
A temperature drop in the lower Stratosphere will accompany the temperature increase near the surface. The shape of the trend down in the Stratosphere should be close to a mirror reflection of the near surface trend up.
The present CO2 level is high and increasing (http://www.esrl.noaa.gov/gmd/ccgg/trends/). It should be fairly easy to show the consequences of AGW predictions if they are valid.
Figure 1. Global average temperature from 1850 through 2008. Annual series smoothed with a 21-point binomial filter by the Met Office. (http://hadobs.metoffice.com/hadcrut3/diagnostics/global/nh+sh/)
It should be noted that the largest part of the last 150 year increase in CO2, which is blamed on human activity, did not occur until after 1940, so the largest temperature rise effects should have occurred in that time. The proponents of AGW have generally used the time period from 1970 to 2000 as the base line for an indicator of the rapid warming. In that base line period, the average temperature rose about 0.50C, which averages to 0.160C per decade. The claim was then made that this would accelerate due to continuing increases in CO2 level. However if we look at the temperature change from 1940 through 2008, the net increase is only 0.30C. This is due to a drop from 1940 to 1970 and a slight drop from 2000 through 2008. Now the average rise for that period is only 0.040C per decade. If the time period from 1850 through 2008 is used as a base, the net increase is just under 0.70C and the average rise is also 0.040C per decade! It is clear that choosing a short selected period of rising temperature gives a misleading result. It is also true that the present trend is down and expected to continue downward for several more years before reversing again. This certainly makes claim 1 questionable.
The drop in temperature from 1940 to 1970 was claimed to have been caused by “global dimming” caused by aerosols made by human activity. This was stated as dominating the AGW effects at that time. This was supposed to have been overcome by activity initiated by the clean air act. In fact, the “global dimming” continued into the mid 1990’s and then only reduced slightly before increasing more (probably due to China and other countries increased activity). If the global dimming was not significantly reduced, why did the temperature increase from 1970 to just past 2000?
A consequence of global dimming is reduced pan-evaporation level. This also implies that ocean evaporation is decreased, since the main cause of ocean evaporation is Solar insolation, not air temperature. The decreased evaporation contradicts claim 2.
Claim 3 has been contradicted by a combination of satellite and air born sensor measurements. While the average lower Troposphere average temperature has risen along with near ground air temperature, and in some cases is slightly warmer, nevertheless the models predicted that the lower Troposphere would be significantly warmer than near ground at the lower latitudes, especially in the tropics. This has not occurred! The following is a statement from:
Synthesis and Assessment Product 1.1
Report by the U.S. Climate Change Science Program
and the Subcommittee on Global Change Research
April 2006
“While these data are consistent with the results from climate models at the global scale, discrepancies in the tropics remain to be resolved”.
Claim 4 implies that the higher latitudes should heat up more than lower latitudes. This is supposed to be especially important for melting of glaciers and permafrost. In fact, the higher latitudes have warmed, but at a rate close to the rest of the world. In fact, Antarctica has overall cooled in the last 50 years except for the small tail that sticks out. See:
http://ff.org/centers/csspp/library/co2weekly/20061013/20061013_02.html
Greenland and the arctic region are presently no warmer than they were in the late 1930’s, and are presently cooling! See:
The overall effect of Antarctic and Greenland are now resulting in net gain (or at least near zero change) of ice, not loss. While some small areas have recently lost and are some are still losing some ice, this is mostly sea ice and thus do not contribute to sea level rise. Glaciers in other locations such as Alaska have lost a significant amount of ice in the last 150 years, but much of the loss is from glaciers that formed or increased during the little ice age, or from local variations, not global. Most of this little ice age ice is gone and some glaciers are actually starting to increase as the temperature is presently dropping. For more discussions on the sea level issue look at the following two sites:
http://docs.google.com/Doc?docid=dnc49xz_19cm8×67fj&hl=en
This indicates that claim 5 is clearly wrong. While sea level will rise a small amount, and has so since the start of the Holocene period, the rise is now only 10 to 15 cm per century, and is not significantly related to the recent recovery from the little ice age, including the present period of warming.
The claims in 6 are particularly interesting. Figure 2 below shows the Global Brightness Temperature Anomaly (0C) in the lower Troposphere and lower Stratosphere made from space.
a) Channel TLT is the lower Troposphere from ground to about 5 km
b) Channel TLS is the lower Stratosphere from about 12 to 25 km
Figure 2. Global satellite data from RSS/MSU and AMSU data. Monthly time series of brightness temperature anomaly for channels TLT, and TLS. Data from: http://www.ssmi.com/msu/msu_data_description.html
The anomaly time series is dominated by ENSO events and slow troposphere warming for Channel TLT (Lower Troposphere). The three primary El Niños during the past 20 years are clearly evident as peaks in the time series occurring during 1982-83, 1987-88, and 1997-98, with the 1997-98 being the largest. It also appears there is an aditional one at 2007. Channel TLS (Lower Stratosphere) is dominated by stratospheric cooling, punctuated by dramatic warming events caused by the eruptions of El Chichon (1982) and Mt Pinatubo (1991). In these, and other volcanic eruption cases, the increased absorption and reflectivity of the dust and aerosols at high altitudes lowered the surface Solar insolation, but since they absorbed more energy, they increased the high altitude temperature. After the large spikes dropped back down, the new levels were lower and nearly flat between large volcanic eruptions. It is also likely that the reflection or absorption due to particulates also dropped, so the surface Solar insolation went back up. It appears that a secondary effect of the volcanic eruptions is present that is unknown in nature (but not CO2)! One possible explanation is a modest but long-term drop in Ozone. It is also clear that the linear fit to the data shown is meaningless. In fact the level drop events seem additive if they overlap soon enough for at least the two cases shown. That is, after El Chicon dropped the level, then Pinatubo occurred and dropped the level even more. Two months after Pinatubo, another strong volcano, Cerro Hudson, also erupted, possibly amplifying the effect. It appears that the recovery time from whatever causes the very slow changing level shift has a recovery time constant of at least several decades.
The computational models that show that the increasing CO2 and CH4 cause most of the present global warming all require that the temperature of the Stratosphere drops while the lower atmosphere and ground heat up. It appears from the above figures that the volcanic activity clearly caused the temperature to spike up in the Stratosphere, and that these spikes were immediately followed by a drop to a new nearly constant level in the temperature. It is clear from the Mauna Loa CO2 data (http://www.esrl.noaa.gov/gmd/ccgg/trends/) that the input of CO2 (or CH4) from the volcanoes, did not significantly increase the background level of this gas, and thus, this cannot be the cause of the drop in the Stratosphere temperature. The ramp up of atmospheric CO2 also cannot explain the step down then level changes in high altitude temperature. Since the surface temperature rise is supposed to be related to the Stratosphere temperature drop, and since a significant surface rise above the 1940 temperature level did not occur until the early 1980’s, it may be that the combination of the two (or more) volcanoes, along with Solar variability and variations in ocean currents (i.e., PDO) may explain the major causes of recent surface temperature rises to about 2002. In fact, the average Earth temperature stopped rising after 2002, and has been dropping for the last few years!
The final question that arises is what prediction has the AGW made that has been demonstrated, and that strongly supports the theory. It appears that there is NO real supporting evidence and much disagreeing evidence for the AGW theory as proposed. That is not to say there is no effect from Human activity. Clearly human pollution (not greenhouse gases) is a problem. There is also almost surely some contribution to the present temperature from the increase in CO2 and CH4, but it seems to be small and not a driver of future climate. Any reasonable scientific analysis must conclude the basic theory wrong!!
Steve Schnieder is hilarious in the “In Search of” episode linked above. He uses Ice Age Scare Tactics to rail against nationalism like a good Internationale Socialist.
He is more of a political activist than scientist.
At least he is not selling carbon indulgences… is he?
Dave Middleton:
“Three complete up half-cycles and two complete down half-cycles would provide a secular upward trend…Particularly since the average amplitude of the up half-cycles is slightly higher than that of the down half cycles.
You seem to be trying very hard not to see what the data is telling you. If each successive peak is higher than the last, and each successive trough is higher than the last, then there is a secular upward trend. It’s absolutely obvious to anyone with basic observational capabilities that an oscillation alone is an extremely poor description of the HadCRUT data since 1850.
Earlier you claimed that “The stratospheric temperature was flat prior to the El Chicon cooling, flat between El Chicon and Pinatubo, and flat after Pinatubo“. I asked you what data and what method you used to calculate these claimed trends, because linear fits to UAH data in the periods concerned gives a negative trend in all three periods. You didn’t answer. Instead, you made some more claims about a number of very short periods, which suggests to me that you don’t realise that over periods of a few years, internal variation obscures long term trends. Would you now specify what dataset you used, and how you derived the trends?
“Well then…Maybe you can cite some period other than 1979-1982 when the Stratosphere was cooling while the Troposphere was warming. From 1983-2009 the Stratosphere and Troposphere curves are always behaving inconsistently with greenhouse warming.”
Incorrect. As I said, in each of the three periods, the stratosphere was cooling. The stratosphere is now about a degree cooler than it was at the start of the satellite record, while the troposphere is about 0.5°C warmer. This is the expected behaviour, in response to rising greenhouse gas concentrations.
“Greenhouse warming, by definition, requires a redistribution of heat from the upper atmosphere to the lower atmosphere.”
Quite wrong.
If it makes you feel better…Every time I use the word “oscillation,” just pretend I used the word “fluctuation.”
Here’s HadCRUT3 & UAH vs. CO2…
CO2vs. Temp
And the same temperature data vs. the length of the Schwabe Cycle…
Schwabe Length vs. Temp
Pretty clearly an oscillating function.
I downloaded the UAH data set from NCDC/NOAA’s …website . I segmented the entire data set in such a way that the massive volcanic warming of the Stratosphere in 1982 and 1991 and the massive ENSO warming of the Troposphere in 1998 did not provide the false impression of stratospheric cooling along with tropospheric warming…Dec 1978 – Apr 2009
Prior to El Chichón (Dec. 1978 – Jan. 1982), the Troposphere warmed while the Stratosphere cooled…This is the only time period of the UAH MSU data that showed a “greenhouse signature…Dec 1978 – Jan 1982
During the El Chichón disruption (Jan. 1982 – June 1984), the Troposphere and Stratosphere had linear cooling trends… Jan 1982 – Jun 1984
Between El Chichón and Pinatubo (June 1984 – June 1990) the Troposphere and Stratosphere had linear cooling trends… Jun 1984 – Jun 1990
During and just after the Pinatubo disruption (June 1990- June 1994), the Troposphere and Stratosphere had linear cooling trends… Jun 1990 – June 1994
In the run-up to the major ENSO event (June 1994 – June 1997), the Troposphere and Stratosphere had linear cooling trends… Jun 1994 – June 1997
During the 1997-1998 ENSO (June 1997 – June 1999), the Troposphere actually had a linear cooling trend; while the Stratosphere had a slight warming trend… June 1997 – June 1999
Between the end of the ENSO and the onset of oceanic cooling in 2003 (June 1999 – Dec. 2003), the Troposphere and Stratosphere both had warming trends… June 1999 – Dec 2003
Since 2003, the Stratosphere and Troposphere have had cooling trends… Jan 2003 – Apr 2009
The only time interval in which the Stratosphere was cooling while the Troposphere was warming was Dec 1978 – Jan 1982.
Since I made those graphs I have also done some work with moving averages…And they show a similar picture. The Stratosphere rarely cooled while the Troposphere was warming.
That’s how the greenhouse effect works. It doesn’t cause more energy to come into Earth’s atmosphere. It retains energy (heat) in the lower atmosphere…Resulting in a redistribution of heat from the upper atmosphere to the lower atmosphere.
Major volcanic eruptions tend to cause an inverse greenhouse effect. That’s why El Chichón and Pinatubo resulted in very significant warming of the Stratosphere concurrent with cooling of the Troposphere. Heat was effectively redistributed from the lower atmosphere to the upper atmosphere.
Neither phenomenon brings more solar heating into the system; they redistribute heat within the system…The system being Earth’s atmosphere.
I think the Spam filter just grabbed my post due to Photobucket links.
I managed to reverse the links for these two segments…
During the El Chichón disruption (Jan. 1982 – June 1984), the Troposphere and Stratosphere had linear cooling trends… Jan 1982 – Jun 1984…Links to June 1984 – June 1990.
Between El Chichón and Pinatubo (June 1984 – June 1990) the Troposphere and Stratosphere had linear cooling trend…Links to Jan. 1982 – June 1984.
RE: Pierre Gosselin (03:24:31) :
“Yesterday my daughter (14) made her skeptic-presentation on climate change in her geography class, and I am pleased to say the result was surprising in very positive way.”
Good show!
Dave Middleton: you can call whatever you’re seeing a fluctuation if you like. There is still a secular upward trend, and it’s rather weird to pretend that there isn’t.
The greenhouse effect does not simply redistribute heat. Heat that would otherwise escape into space is retained in the atmosphere. This is pretty basic stuff, and I’m surprised you don’t know it.
As for your graphs, well, in any period of just a few years, internal variation dominates and long term trends are not apparent. I said that before, you made no comment so I presume you were unaware of that as well. Notwithstanding that they are over periods too short to be meaningful, your graphs stop and start at very strange places. Pinatubo erupted in June 1991, not June 1990. El Chichón erupted in March 1982, not January 1982. The effects of these eruptions on stratospheric temperatures were over by January 1984 and June 1993, not June 1984 and June 1994. Why did you pick the dates you did?
RW (19:02:09) :
For the hypothetical equilibrium earth system, the greenhouse effect does not “retain” anything. The TOA flux out still has to match the TOA flux in. If the earth is actively warming, then yes there may be a small imbalance.
I think by practically anyone’s reckoning, we’re barely on the edge of having more than a “few” years of any consistent type of climate measurement (bristlecones notwithstanding).
oms: try a little thought experiment. Imagine a planet with no atmosphere. It’s in radiative equilibrium. Flux in = flux out. Now imagine an atmosphere made of CO2 appears. Leave it a bit, until it reaches radiative equilibrium.
You would find that the surface would warm, and that it would now radiate more energy than it directly receives from the Sun. Clearly, heat is being retained that would otherwise be lost into space. Nothing has been redistributed, because there was nowhere for it to be redistributed from.
RW: thanks for the little thought experiment. After thinking about it, it still seems to me that all the downward flux is still accounted for by upward flux, at both the surface and at the TOA level (whatever you define that to be), so I guess we have somewhat different ideas of what “retention” (or maybe “equilibrium”) means .
On second thought, I can understand the your usage. If you have a dam at equilibrium, you think of the reservoir behind it as being “retained” so okay your point is fine.
Dave Middleton’s original statement, “Greenhouse warming, by definition, requires a redistribution of heat from the upper atmosphere to the lower atmosphere,” doesn’t seem 100% correct (in that I don’t believe it to be quite definitional) but it doesn’t seem to be as wrong as you are making it out to be either.
It is a simplification. But heat redistribution is the effective result. If Earth’s atmosphere lacked greenhouse gases…The lower atmosphere would be colder and the upper atmosphere would be warmer.
There’s an apparent secular positive trend in three peaks and two troughs of any symmetrical oscillating function. There is also an apparent secular trend in any asymmetrical oscillating function. A complex oscillating function will also appear to have secular trends due to the underlying lower frequency function.
However, there is no “secular” relationship between CO2 and temperature. If there was, this chart would look a lot different than it does…Phanerozoic CO2 vs. Temp.
As far as the Stratosphere goes, it is a “step” function; see Ramaswamy et. al. (2006)…
Ramaswamy was able to replicate the step function with a combination of natural and anthropogenic effects. The bulk of the anthropogenic cooling was the result of ozone depletion (Isn’t stratospheric cooling the primary evidence for stratospheric ozone depletion?). However, if he removed the volcanic effects, the model predicted a steady decline in stratospheric temperatures; which was inconsistent with the observed temperature trends.
The result of the greenhouse effect is a redistribution of energy (heat). CO2 is generally “transparent” to incoming high frequency (UV) solar radiation and “opaque” to certain bandwidths of low frequency (IR) radiation. After the solar radiation heats the Earth’s surface, some of this energy is radiated back into the atmosphere. Certain bandwidths of the radiated IR are “absorbed” or “retained” by C2. This “warms” the lower atmosphere. The greenhouse effect results in the lower atmosphere effectively retaining a higher percentage of the outgoing IR. Since heat is retained in the lower atmosphere, less Earth-radiated IR reaches the upper atmosphere…leading to cooling of the upper atmosphere.
Hence the ultimate effect is a redistribution of heat within the atmosphere.
Since almost all of the stratospheric cooling over the satellite record is due to volcanic events and stratospheric ozone depletion…There’s little (if any) stratospheric cooling left over to account for much enhancement of tropospheric greenhouse warming over the past 30 years.
I picked the dates to fully isolate the effects of the volcanic events and the 1997-1998 ENSO.
As far as your comment about “internal variation”….I’m certain that advocates of the Ptolemaic solar system invoked “internal variation” and natural variability quite often in dismissing criticisms of the epicycles hypothesis to explain away retrograde motion.
The Earth’s climate did not behave in a manner consistent with CO2-driven global warming from the dawn of the Cambrian until 1978…And since 1998 it has not behaved in a manner consistent with CO2-driven global warming. And since the Stratosphere did not concurrently cool with the warming of the Troposphere, it really didn’t behave a manner consistent with CO2-driven global warming from 1979-1998 either.
“If Earth’s atmosphere lacked greenhouse gases…The lower atmosphere would be colder and the upper atmosphere would be warmer.”
No. Both would be colder, in that case. Think about it. What would be heating the upper atmosphere?
“There’s an apparent secular positive trend in three peaks and two troughs of any symmetrical oscillating function.”
Nope.
“However, there is no “secular” relationship between CO2 and temperature.”
That is an absurd claim.
“If there was, this chart would look a lot different than it does…Phanerozoic CO2 vs. Temp.”
Presumably you were unaware that geological and solar processes dominate over the longest timescales.
“However, if he removed the volcanic effects, the model predicted a steady decline in stratospheric temperatures; which was inconsistent with the observed temperature trends.”
Yes, if you remove events which actually occurred, it’s hardly a surprise that you can’t replicate what actually occurred.
“Since almost all of the stratospheric cooling over the satellite record is due to volcanic events and stratospheric ozone depletion…There’s little (if any) stratospheric cooling left over to account for much enhancement of tropospheric greenhouse warming over the past 30 years.”
Try reading the Ramaswamy paper again. Here’s a small bit, which you already directly quoted but don’t seem to have noticed: “the overall lower stratospheric temperature decline is driven primarily by the depletion of ozone, and to a lesser extent by the increase in well-mixed greenhouse gases.”
“I picked the dates to fully isolate the effects of the volcanic events and the 1997-1998 ENSO.”
Temperatures are not influenced by volcanoes until after the eruption. You chose periods that ended three months and one year before the two major eruptions. Why?
“As far as your comment about “internal variation”….I’m certain that advocates of the Ptolemaic solar system invoked “internal variation” and natural variability quite often in dismissing criticisms of the epicycles hypothesis to explain away retrograde motion.”
‘Internal variation’ in a climate context is also known as ‘weather’. Are you denying that weather exists?
“The Earth’s climate did not behave in a manner consistent with CO2-driven global warming from the dawn of the Cambrian until 1978”
At no time in the Earth’s history has CO2 not absorbed infrared radiation. At no time in the Earth’s history has its radiative balance been independent of the CO2 concentration.
“…And since 1998 it has not behaved in a manner consistent with CO2-driven global warming.”
The average temperature in the 2000s is almost 0.2°C higher than the average temperature in the 1990s.
“And since the Stratosphere did not concurrently cool with the warming of the Troposphere, it really didn’t behave a manner consistent with CO2-driven global warming from 1979-1998 either.”
The stratosphere did concurrently cool. Try reading the Ramaswamy paper again.
So an increase in greenhouse gases cools the Stratosphere and a decrease in greenhouse gases cools the Stratosphere?
How is stratospheric cooling evidence of tropospheric greenhouse warming if the Stratosphere cools in response to any change in GHG’s?
You got me there. I was doing the “math” in by head. It’s an apparent negative secular trend. The point was that a symmetrical oscillating function can impart an apparent secular trend where there is no true secular trend.
It may sound absurd to you; but there is no secular relationship between CO2 and temperature. Pleistocene ice core data suggest that there was a cyclical relationship…However, if the ice core CO2 data are correct, that relationship has changed… LINK …If the relationship was truly secular, it would be quite a bit hotter today than it was ~130,000 years ago during the Sangamon interglacial. But the Sangamon was considerably warmer than it is now (several degrees C) and sea level was 5-8 meters higher…Yet CO2 was at most ~300ppm (if the ice core data are correct).
If the postulated feed back mechanisms are negated, CO2’s greenhouse effect is logarithmic and not linear. So any secular relationship would vanish with increasing CO2 concentrations.
That’s mind boggling. I must’ve wasted the last 30+ years of my life as a geophysicist…All this time I thought geological process dominated over short periods of time…(slaps own forehead).
So…Let’s make sure I understand. The secular relationship between CO2 and temperature is only operative over intermediate periods of time…Is that correct?
The cooling from 1942-1978 and from 2003 to the present are such short periods of time that “internal variation” and natural variability overwhelm the greenhouse effect of increasing CO2. And the Phanerozoic lack of correlation is due to “geological and solar processes” overwhelming the anti-greenhouse effect of decreasing CO2. So…I guess that this interglacial lacks the same cyclical relationship between CO2 and temperature because ““geological and solar processes” suddenly changed during the Holocene transgression? Or is it just “internal variation” and natural variability?
That steady decrease should be apparent in the observed data before, between and after the two volcanic events. It is not.
I noticed the words “primarily” and “lesser.” That’s why I quoted that particular passage.
Ozone depletion (if it is really occurring) cools the Stratosphere because the ozone-depleted upper atmosphere absorbs less incoming UV radiation than an ozone-enriched upper atmosphere would absorb. Well mixed greenhouse gasses would add to that cooling by retaining more outgoing IR radiation in the lower atmosphere.
Ozone depletion-driven stratospheric cooling wouldn’t have to be concurrent with tropospheric warming. GHG-driven tropospheric warming would have to be complemented by a concurrent stratospheric cooling.
I picked them to put the “bumps” in the middle of the segments that included the bumps. I could pick the segments in almost any configuration and the curves almost never approach one-another when the Stratosphere curve is placed above the Troposphere curve.
Ideally it should look something like a Neutron-Density curve on a well log through a gas bearing sandstone. The two curves should approach one another, if not cross over, during periods in which there is an enhancement of greenhouse warming of the lower atmosphere.
You got me again…I am a weather denialist. It’s all climate; there’s no such thing as weather.
That explains the lack of correlation between CO2 and temperature quite well.
And?
When did the climate start paying attention to the human-derived numerical values of decades?
According to the UAH Lower Troposphere global temperature anomalies, the Earth warmed 0.96 C from Dec. 1978 to Apr. 1998 and then cooled -0.67 C from Apr. 1998 to Apr. 2009.
That works out to a warming rate of 0.62 C per decade from Dec. 1979 to Apr. 1998 and a cooling rate of -0.73 per decade from Apr. 1998 to the present.
Let me guess…Dec. 1978 to Apr. 1998 is significant and Apr. 1998 to Apr. 2009 is “internal variation”…Right?
I ‘ve got a copy of it right in front of me.
The Stratosphere cooled in the immediate aftermath of the major volcanic events. Before, between and after those events stratospheric temperatures remained relatively flat, irrespective of what the Troposphere was doing…”Observations reveal that the substantial cooling of the global lower stratosphere over 1979–2003 occurred in two pronounced steplike transitions. These arose in the aftermath of two major volcanic eruptions, with each cooling transition being followed by a period of relatively steady temperatures.”
“So an increase in greenhouse gases cools the Stratosphere and a decrease in greenhouse gases cools the Stratosphere?”
Why should there be one fixed linear relation between CO2 concentrations and stratospheric temperatures that applies for all possible values of CO2? I invite you again to think about the case of no greenhouse gases. You said that the stratosphere would be warmer in that case than it is today. What would be heating it?
You said “There’s an apparent secular positive trend in three peaks and two troughs of any symmetrical oscillating function”, but then later “It’s an apparent negative secular trend. The point was that a symmetrical oscillating function can impart an apparent secular trend where there is no true secular trend.” Given
that you claimed that hadcrut temperature data could be represented by an oscillating function, and that there were three peaks and two troughs, how do you reconcile the observed upward trend with the mathematically inevitable downward trend that would actually be derived for an oscillating function over 2.5 oscillations containing three peaks and two troughs?
“…there is no secular relationship between CO2 and temperature”
Now this is simply denialism. If this were true, there would be no greenhouse effect.
“If the postulated feed back mechanisms are negated, CO2’s greenhouse effect is
logarithmic and not linear. So any secular relationship would vanish with increasing CO2 concentrations.”
Non sequitur. Logarithmic relationships don’t ever vanish.
“So…Let’s make sure I understand. The secular relationship between CO2 and temperature is only operative over intermediate periods of time…Is that correct?”
I’m very surprised that you seem to be struggling with very simple concepts. There is, of course, always and inevitably a relationship between the concentration of a greenhouse gas and global temperatures. If you expect as a result of that to see a 100% correlation between the two variables over any and all timescales, then your science intuition is woeful. So, let me make sure I understand: do you think there should be a 100% correlation between CO2 concentrations and temperatures over all timescales?
“That steady decrease should be apparent in the observed data before, between and after the two volcanic events. It is not.”
I already told you that in all three periods not affected by volcanoes, the tren in stratospheric temperatures was negative. You only got a different result by wrongly excluding data that was not affected by the eruptions, such as the entire year before Pinatubo erupted.
“You got me again…I am a weather denialist. It’s all climate; there’s no such thing as weather.”
OK…
“When did the climate start paying attention to the human-derived numerical values of decades?”
That’s a rather hilariously odd comment. Are you saying that no natural phenomenon can be measured using human-invented units? How do you propose to measure climate trends? Tell me the units you want to use and I’ll tell you the answer,
and we can pretend decades don’t exist if you like. It won’t change the underlying physics.
“According to the UAH Lower Troposphere global temperature anomalies, the Earth
warmed 0.96 C from Dec. 1978 to Apr. 1998 and then cooled -0.67 C from Apr. 1998 to Apr. 2009. That works out to a warming rate of 0.62 C per decade from Dec.
1979 to Apr. 1998 and a cooling rate of -0.73 per decade from Apr. 1998 to the present.”
Drawing a line between two points is not how trends are calculated.
“Let me guess…Dec. 1978 to Apr. 1998 is significant and Apr. 1998 to Apr. 2009 is “internal variation”…Right?”
If you want to find out the answer to this you need first of all to calculate the trends properly, using all the data, and then to choose an appropriate statistical model for the noise pattern in the data to calculate the error on the trend. If the error is larger than the trend for a given period, then the trend is not significant.
Then, why does an increase of “well mixed greenhouse gases” cool the Stratosphere and an absence of “well mixed greenhouse gases” also cool the Stratosphere.
I also said that asymmetric oscillating functions can have apparent, but insignificant, linear secular trends and that an underlying lower frequency/higher amplitude oscillating function can also impart an apparent secular trend.
No. It just means that the greenhouse effect would not significantly vary with variations in the atmospheric concentration of CO2.
It’s not a no sequitor; it’s an effective approximation. Logarithmic functions don’t vanish in exactly the same way asymptotic functions never reach infinity.
If there was a secular or linear relationship between CO2 and temperature there would be a long-term correlation between CO2 and temperature. There is no such correlation at the Phanerozoic scale. The Pleistocene cyclical relationship went bust somewhere around 1939 (if the ice core CO2 are correct). The correlation between CO2 and ~0.5 C of warming from 1908-1942 is different from the _0.5 C of warming from 1978-2003. And CO2 concentrations increased faster during the
~0.2 C of cooling from 1942-1978 than they increased during the 1908-1942 warming…And CO2 concentrations have increased at the same rate (if not faster) during the ~0.4 C of cooling since 2003 than they did during the 1978-2003 warming.
No. The trend was not negative between El Chicon and Pinatubo; nor is it negative since Pinatubo. It was slightly negative before El Chicon. The Stratosphere warmed slightly from Jan. 1995 to Jan 2002…As did the Troposphere. Since Jan. 2002, both the Stratosphere and the Troposphere have linear cooling trends. Essentially, the Stratosphere warmed during both volcanic events and the cooled rapidly in a “steplike” transition; assuming a generally neutral trend after the passing of each volcanic event.
From Ramaswamy et. al.: ”Observations reveal that the substantial cooling of the global lower stratosphere over 1979–2003 occurred in two pronounced steplike transitions. These arose in the aftermath of two major volcanic eruptions, with each cooling transition being followed by a period of relatively steady temperatures.”
To the climate “decades” are “pretend.” The underlying physics doesn’t cause climate variations to fit into human decades.
So…April 2009 was warmer than April 1998? I would have guessed that +0.76 was a larger number than +0.09.
Drawing a linear trend-line through a non-linear function is also another way to not properly calculate a trend. A 6th order polynomial fit of the UAH LT data yields an “S” shaped curve that starts just below 0 in Dec 1978 and finishes just above 0 in Apr. 2009. It looks a lot like an oscillation. And it starts and ends very close to phase shifts in the PDO.
A linear trend through the UAH LT data has an R^2 of 0.2792…The sixth order polynomial has an R^2 of 0.3513.
It’s been a while since I took statistics…Isn’t R^2 a measure of how well a trend fits a function?
Use all of the data? If I use all of the data, “geological and solar” processes overwhelm variations in CO2. If I don’t use enough data, “internal variation” and natural variability overwhelm the variations in CO2.
So…I have to use just the right bits of data that fit the AGW narrative? Sounds like cherry-picking to me.
You seem to be struggling with a number of basic misconceptions:
1. You are denying that CO2 is a greenhouse gas, which is absurd; that has been known for 150 years.
2. You don’t seem to understand a logarithmic relationship. If y ∝ log(x), then doubling x always results in the same increase in y. Always. This relationship never ‘vanishes’ and it has nothing in common with asymptotic functions.
3. When you say “If there was a secular or linear relationship between CO2 and temperature there would be a long-term correlation between CO2 and temperature. There is no such correlation at the Phanerozoic scale”, you would only be right if CO2 was the only thing changing. How could you be unaware that over those timescales, that is a disastrously wrong assumption?
4. You don’t understand how to calculate trends. Drawing a line joining two arbitrary points in the data is not a valid method. Using a 6th order polynomial is absurd over-fitting. Presumably you are unaware that if you were to do a 12th order polynomial, you’d get an even better fit – and even less meaningful.
I would be amazed if you really genuinely couldn’t understand these four points. You seem to be affecting a sort of pseudo-ignorance, for reasons I can’t begin to imagine.
By the way, I’ve asked you twice and you haven’t answered: if there were no greenhouse gases in the atmosphere, what would be heating the upper atmosphere to make it warmer than it is today?
No. I have never denied that CO2 is a greenhouse gas. I have clearly stated on numerous occasions that the only facet of the AGW hypothesis that is correct, is the assertion that CO2 is a greenhouse gas.
However the greenhouse effect of CO2 is a logarithmic function of diminishing returns. Hence, there is no secular relationship between CO2 and temperature.
Most of the greenhouse effect comes from water vapor…A little bit of CO2 is enough to yield a disproportionately large percentage of CO2’s entire greenhouse warming potential. Each additional unit of CO2 yields less greenhouse warming than the unit preceding it.
If “x” was CO2 and “y” was delta (temp) in the equation y=ln(x)…
+0 CO2 -> +0 T
+1 CO2 -> +2 T
+2 CO2 -> +3 T
+8 CO2 -> +4 T
Of course the formula is not so simple as T=ln(CO2).
I should have said that an asymptotically increasing function never reaches infinity in the same way that a logarithmic function never vanishes.
Because irrespective of plate tectonics and all of the other massive changes apart from CO2…Earth’s hothouse phases had a remarkably consistent average temperature of about 22 C…And three of the four icehouse phases pretty well settled in with ~12 C average temperatures.
The continents moved all over the place…building and tearing down mountain ranges several times over…CO2 more or less declined in a generally secular manner…Yet the temperatures generally oscillated from 12 C to 22 C.
The icehouse vs. hothouse phases may have been dictated by plate tectonics or astrophysical phenomena…But CO2 appears to have played no role in that cycle.
No. I understand that quite well. But I also know how to recognize non-linear “nested” cycles. Like the First Order Relative Changes of Sea Level and the Second Order Relative Changes of Sea Level on this chart.
A third or sixth order polynomial would fit the First Order quite well. A twelfth order polynomial might just fit the Second Order quite well. A linear trend-line would be meaningless on either.
I’m amazed that I’ve put up with your insults for so long…Maybe my temper works on geological time.
You are just not sufficiently familiar enough with geology and geophysics to be able to look at climate change from the same perspective that I do. I fail to see why that elicits such obnoxiousness on your part. Oh well… C’est la vie.
Because the Sun would still be warming the Earth. A heat source will still warm air that is devoid of greenhouse gases.
The amount of incoming UV radiation would be exactly the same as it is now. The same amount would reach the Earth’s surface and warm it. The Earth would radiate back the same amount of IR radiation. Since less of the IR would be warming the lower atmosphere, more of it would be available to warm the upper atmosphere on its way back into space.
From Understanding the Earth by Geoff Brown (a geology text book)…
“Stratospheric aerosols alter the global radiation budget mainly by absorbing and backscattering incoming solar radiation, and they also absorb some outgoing infrared radiation.” Aerosols have a double-warming effect on the upper atmosphere. Incoming UV and outgoing IR both warm stratospheric aerosols.
In the absence of a greenhouse effect…The same amount of incoming UV would warm the Stratosphere and more outgoing IR would warm the Stratosphere.
Am I certain that this would result in a warmer Stratosphere? No. Too many variables to consider.
Now, perhaps you will return the favor an explain how an increase of “well mixed greenhouse gases” cool the Stratosphere and an absence of “well mixed greenhouse gases” also cool the Stratosphere.
Dave Middleton,
You are right, of course. But you’re feeding a troll. The only reason his snarky attitude isn’t insufferable is because his beliefs are so easy to deconstruct. But on general principles, it’s best not to feed trolls.
You are correct…And I hope I am not diminishing the collegiality of WUWT…But he (or she) keeps hanging curveballs…Swinging away is just so irresistible…;)
“I have never denied that CO2 is a greenhouse gas.”
You said “the greenhouse effect would not significantly vary with variations in the atmospheric concentration of CO2“. If CO2 is a greenhouse gas, that would be impossible.
“However the greenhouse effect of CO2 is a logarithmic function of diminishing returns. Hence, there is no secular relationship between CO2 and temperature.”
That’s interesting. You’re saying that there’s a logarithmic relationship, therefore there’s no relationship. Let me give you the corrected version of what you said: the greenhouse effect of CO2 is a logarithmic function. Hence, there is a relationship between CO2 and temperature.
“I should have said that an asymptotically increasing function never reaches infinity in the same way that a logarithmic function never vanishes.”
If you’d said that, you’d still be wrong. y=1/x is an asymptotic function. as
x tends to infinity, y tends to a fixed value – in this case, zero. y=log(x) is
not an asymptotic function. As x tends to infinity, y also tends to infinity,
and not a fixed value.
“irrespective of plate tectonics and all of the other massive changes apart from CO2, Earth’s hothouse phases had a remarkably consistent a
verage temperature of about 22 C. And three of the four icehouse phases pretty well settled in with ~12 C average temperatures.”
Ah, I see the problem. Just how accurate do you believe that 22C figure is? Do you know how it was estimated? Do you know what other estimates are available? If not, why not? If so, why do you prefer this one?
“The icehouse vs. hothouse phases may have been dictated by plate tectonics or astrophysical phenomena. But CO2 appears to have played no role in that cycle.”
The Sun was fainter when it was younger, and liquid water could not have existed on Earth without a much greater greenhouse effect than exists today. This is a simple fact but one which you appear to be entirely unaware of.
“A third or sixth order polynomial would fit the First Order quite well. A twelfth order polynomial might just fit the Second Order quite well. A linear trend-line would be meaningless on either.”
If you think you can meaningfully fit a 12th-order polynomial to any physical phenomenon, I’m afraid you’re horribly mistaken.
“You are just not sufficiently familiar enough with geology and geophysics to be able to look at climate change from the same perspective that I do. I fail to see why that elicits such obnoxiousness on your part. Oh well, C’est la vie”
You’re not sufficiently familiar with basic physics or statistics to come to any
sensible conclusion about climate change, as we can see from the litany of basic misconceptions that appear throughout your posts.
That’s because the relationship is one of “diminishing returns”…A logarithmic relationship. Each additional unit of CO2 yields less greenhouse warming than the prior unit. So there is no linear or secular relationship.
If CO2 provides 25% of Earth’s greenhouse warming (~30 C)…285ppm of CO2 was yielding 7.5C of warming. A doubling of that CO2 level to 580ppm could not raise the Earth’s temperature by more than 1.5 C to 2.0 C (without positive feedback mechanisms).
0 to 285ppm -> 7.5 C
285 to 570ppm -> 1.75 C
Remarkably similar to Delta-T = ln(CO2). The first 285ppm yields four times as much warming as the next 285ppm. If you extrapolate this relationship to 4000ppm, you’ll understand why CO2 and temperature had no secular relationship throughout the Phanerozoic Eon (the last ~600 million years).
Now…Since the Earth has been cooling while CO2 has climbed from 375 to 385ppm and since the Earth was warmer in the Sangamon Interglacial with only about 315ppm CO2…In fact the Earth was warmed in each of the last four interglacials with less CO2 (if the ice cores are right – a big IF)…It should be apparent that there are no significant positive feedback mechanisms operating. In fact, the feedback mechanisms pretty well have to be negative.
In an asymptotically increasing function delta-y increases exponentially with linear increases in delta-x. In a logarithmic function (like y=ln(x)) delta-y decreases exponentially with linear increases in delta-x.
Hence a logarithmic function vanishes in exactly the same way that an asymptotically increasing function never reaches infinity.
Think Douglas Adams…”The Vogon Constructor Ship hung in the sky exactly like a rock doesn’t.”
It’s as accurate as an estimate can be for something that happened so long ago and has been averaged over such a long time period. Past temperatures are largely reconstructed from oxygen isotope ratios and from paleoclimatological/paleogeographical reconstructions.
One “alternative” reconstruction that I am aware of is Royer (2004). He used a pH modifier to force the temperature data to “fit” the CO2 levels. I believe that the pH modifier was based on CO2 levels. Nir Shaviv and Jan Veizer concluded that…
This model of the Phanerozoic climate has been the standard since at least the 1970s… LINK. It’s what I was taught way back in the Upper Pleistocene.
Could this paradigm one day be shifted? Sure it could. But force-fitting the stable isotope temperature data to the CO2 levels using a CO2-derived pH flux adjustment, is not really very valid.
Maybe so…But you are talking about the pre-Phanerozoic. Very little is known about the pre-Phanerozoic atmosphere. The general consensus is that the Earth’s atmosphere evolved through three main phases.
The Earth’s first atmosphere formed during the Hadean Period and is thought to have been mostly water vapor and CO2, with lesser amounts hydrogen-sulfur compounds, methane, CO and other gases. The Hadean gets its name from Hades…A generally warm place. Much of the Earth’s surface was molten during the Hadean. Molten rocks are kind of hot; even under a faint sun.
From 3.8 to 3.4 billion years ago a second atmosphere formed during the Achaean Period…
“The atmosphere was very different from what we breathe today; at that time, it was likely a reducing atmosphere of methane, ammonia, and other gases which would be toxic to most life on our planet today. Also during this time, the Earth’s crust cooled enough that rocks and continental plates began to form.”
Some studies have suggested that the Achaean was more dominated by CO2 than CH4. I suppose that’s possible. Even with a logarithmically declining greenhouse effect, CO2 could yield an awful lot of atmospheric warming with concentrations measured in 100’s of thousands of ppm…
ln(30) = 3.4, ln(90) = 4.5, ln(180) = 5.2, ln(285) = 5.7, ln(570) = 6.3, ln(4,000) = 8.2, ln(800,000) = 13.6
So, an 80% CO2 atmosphere should be significantly warmer than any atmosphere with less than 0.001% CO2. But variations in CO2 in the 100’s of ppm will not yeld much variation in temperature.
The Earth’s current atmosphere was generally in place about 600 million years ago. Trace gases have varied over the last 600 million years; but the Nitrogen-Oxygen atmosphere that The Phanerozoic Eon, it the geological time period in which life as we know it came to be. Phanerozoic means “visible life”. It was during this period that eukaryotic life literally exploded into evolution.
It is during the Phanerozoic Eon that CO2 and temperature demonstrate no secular relationship because the very minor greenhouse-effect differences between 185ppm and 4,000ppm CO2 are totally obliterated by geological, solar and weather processes.
Then don’t ever become a seismic data processor or a sequence stratigrapher…because the name of both of those games is cyclical resolution of physical phenomena.
As long as the sample rate of your data is at least twice the highest frequency you are trying to resolve, you can obtain meaningful cyclical resolution without aliasing. The maximum resolvable frequency based on sample rate is known as the Nyquist Frequency.
Polynomial trend-line functions are analogous to seismic wavelets. The higher the polynomial – the higher the frequency – the higher the resolution. A densely sampled data set, like the UAH monthly temperature anomaly series can return meaningful cyclical information with polynomial trend-line functions.