What Do We Think About Climate Change

Small extract of data from EPICA ice core records for the last deglaciation period. (Siegenthaler et al. 2005)

The arrows indicate clearly that, based on the data shown in this graph, concentration maxima occured consistently after temperature maxima.

 

quoting a ten year old paper is usually safe but in this case not so much. The issue of ice permeability has pretty much resolved this so called "lag"

perfect example of Jerry's famous quote

you aint going to learn
what you dont want to know

love
B

PS
the point is moot anyway cause we have "artificially" changed the chemistry of the atmosphere, "natural" processes whatever they might have been have nothing to do with whats going on today. What does make a difference is the physical characteristics that make CO2 a greenhouse gas. The results of this artificial alteration in the chemistry of the atmosphere is a measurable increase in temps in lockstep with the industrial age, and at a rate that is unprecedented in the historical climate record.

 

Which is the best man to deal with –he who knows nothing about a subject, and, what is extremely rare, knows that he knows nothing, or he who really knows something about it, but thinks that he knows all?

—Thoreau, Walking

 

Atmospheric Carbon Dioxide Concentration Across the Mid-Pleistocene Transition
Bärbel Hönisch,1 N. Gary Hemming,1,2 David Archer,3 Mark Siddall,4 Jerry F. McManus1
Science 19 June 2009: Vol. 324. no. 5934, pp. 1551 - 1554
DOI: 10.1126/science.1171477


"The dominant period of Pleistocene glacial cycles changed during the mid-Pleistocene from 40,000 years to 100,000 years, for as yet unknown reasons. Here we present a 2.1-million-year record of sea surface partial pressure of CO2 (PCO2), based on boron isotopes in planktic foraminifer shells, which suggests that the atmospheric partial pressure of CO2 (pCO2) was relatively stable before the mid-Pleistocene climate transition. Glacial PCO2 was ~31 microatmospheres higher before the transition (more than 1 million years ago), but interglacial PCO2 was similar to that of late Pleistocene interglacial cycles (<450,000 years ago). These estimates are consistent with a close linkage between atmospheric CO2 concentration and global climate, but the lack of a gradual decrease in interglacial PCO2 does not support the suggestion that a long-term drawdown of atmospheric CO2 was the main cause of the climate transition."

http://www.sciencemag.org/cgi/content/abstract/324/5934/1551

From the text:
"We therefore conclude that CO2 was unlikely to have been the main driver of the Mid Pleistocene Transition."

 

Stable Carbon Cycle–Climate Relationship During the Late Pleistocene
Urs Siegenthaler, Thomas F. Stocker, Eric Monnin,1 Dieter Lüthi, Jakob Schwander, Bernhard Stauffer, Dominique Raynaud, Jean-Marc Barnola, Hubertus Fischer, Valérie Masson-Delmotte, Jean Jouzel
Science 25 November 2005: Vol. 310. no. 5752, pp. 1313 - 1317
DOI: 10.1126/science.1120130

"A record of atmospheric carbon dioxide (CO2) concentrations measured on the EPICA (European Project for Ice Coring in Antarctica) Dome Concordia ice core extends the Vostok CO2 record back to 650,000 years before the present (yr B.P.). Before 430,000 yr B.P., partial pressure of atmospheric CO2 lies within the range of 260 and 180 parts per million by volume. This range is almost 30% smaller than that of the last four glacial cycles; however, the apparent sensitivity between deuterium and CO2 remains stable throughout the six glacial cycles, suggesting that the relationship between CO2 and Antarctic climate remained rather constant over this interval."

http://www.sciencemag.org/cgi/content/abstract/sci;310/5752/1313

From the text:

"The lags of CO2 with respect to the Antarctic temperature over glacial terminations V to VII are 800, 1600, and 2800 years, respectively, which are consistent with earlier observations during the last four glacial cycles."

 

Transient simulations of Holocene atmospheric carbon dioxide and terrestrial carbon since the Last Glacial Maximum
Fortunat Joos, Climate and Environmental Physics, Physics Institute, University of Bern, Bern, Switzerland
Stefan Gerber, Climate and Environmental Physics, Physics Institute, University of Bern, Bern, Switzerland
I. C. Prentice, Department of Earth Sciences, University of Bristol, Bristol, UK
Bette L. Otto-Bliesner, National Center for Atmospheric Research, Boulder, Colorado, USA
Paul J. Valdes, School of Geographical Sciences, University of Bristol, Bristol, UK

GLOBAL BIOGEOCHEMICAL CYCLES, VOL. 18, GB2002, 18 PP., 2004
doi:10.1029/2003GB002156
Received 24 September 2003; accepted 18 February 2004; published 3 April 2004.

Conflicting hypotheses are investigated for the observed atmospheric CO2 increase of 20 ppm between 8 ka BP and pre-industrial time. The carbon component of the Bern Carbon Cycle Climate (Bern CC) model, which couples the Lund-Potsdam-Jena Dynamic Global Vegetation Model to an atmosphere-ocean-sediment component, is driven by climate fields from time-slice simulations of the past 21 ka with the Hadley Centre Unified Model or the NCAR Climate System Model. The entire Holocene ice core record of CO2 is matched within a few ppm for the standard model setup, and results are broadly consistent with proxy data of atmospheric 13CO2, mean ocean δ13C, and pollen data, within their uncertainties. Our analysis suggests that a range of mechanisms, including calcite compensation in response to earlier terrestrial uptake, terrestrial carbon uptake and release, SST changes, and coral reef buildup, contributed to the 20 ppm rise. The deep sea δ13C record constrains the contribution of the calcite compensation mechanism to 4–10 ppm. Terrestrial carbon inventory changes related to climate and CO2 forcing, the greening of the Sahara, peat buildup, and land use have probably influenced atmospheric CO2 by a few ppm only. The early Holocene CO2 decrease is quantitatively explained by terrestrial uptake and calcite compensation in response to terrestrial uptake during the glacial-interglacial transition. The recent hypothesis by Ruddiman [2003] that anthropogenic land use caused a 40 ppm CO2 anomaly over the past 8 ka, preventing the climate system from entering a new glacial, would imply an anthropogenic emission of 700 GtC and a decrease in atmospheric δ13C of 0.6 permil. This is not compatible with the ice core δ13C record and would require an upward revision of land use emission estimates by a factor of 3 to 4.

 

Ice Core Records of Atmospheric CO2 Around the Last Three Glacial Terminations
Hubertus Fischer, Martin Wahlen, Jesse Smith, Derek Mastroianni, Bruce Deck
Scripps Institution of Oceanography, Geosciences Research Division, University of California San Diego, La Jolla, CA 92093-0220, USA.
Science 12 March 1999: Vol. 283. no. 5408, pp. 1712 - 1714
DOI: 10.1126/science.283.5408.1712

"Air trapped in bubbles in polar ice cores constitutes an archive for the reconstruction of the global carbon cycle and the relation between greenhouse gases and climate in the past. High-resolution records from Antarctic ice cores show that carbon dioxide concentrations increased by 80 to 100 parts per million by volume 600 ± 400 years after the warming of the last three deglaciations. Despite strongly decreasing temperatures, high carbon dioxide concentrations can be sustained for thousands of years during glaciations; the size of this phase lag is probably connected to the duration of the preceding warm period, which controls the change in land ice coverage and the buildup of the terrestrial biosphere."

(bolded is mine)

 

Following last series of deglaciations, atmospheric CO2 concentrations exhibit no net change for thousands of years, during which period air temperatures drop all the way back to values characteristic of glacial times for the next glaciation. Then, when CO2 finally began to decline, air temperatures remain constant for a few thousand years, after which they actually rose for some other thousands of years. And even when the two parameters increase in unison, as they did during the three most recent glacial terminations, temperature always rose first, followed by CO2 concentrations some 400 to 1,000 years later.

 

Now let's switch to other matters than the clear CO2 lagging of temperature.
Now we'll concentrate on the limited CO2 greenhouse effect and how feedback with water vapour is needed by the AGW proponents to explain the observed late temerature increase. This has been much discussed already in this thread, but there's always new information coming. This one is pretty interesting:

Trends in middle- and upper-level tropospheric humidity from NCEP reanalysis data
Garth Paltridge & Albert Arking & Michael Pook
Theoretical and Applied Climatology
DOI 10.1007/s00704-009-0117-x
Received: 21 July 2008 / Accepted: 4 February 2009

http://www.gerkynet.com/meteo/paltrigde08.pdf

Abstract

"The National Centers for Environmental Prediction (NCEP) reanalysis data on tropospheric humidity are examined for the period 1973 to 2007. It is accepted that radiosonde-derived humidity data must be treated with great caution, particularly at altitudes above the 500 hPa pressure level. With that caveat, the face-value 35-year trend in zonal-average annual-average specific humidity q is significantly negative at all altitudes above 850 hPa (roughly the top of the convective boundary layer) in the tropics and southern midlatitudes and at altitudes above 600 hPa in the northern midlatitudes. It is significantly positive below 850 hPa in all three zones, as might be expected in a mixed layer with rising temperatures over a moist surface. The results are qualitatively consistent with trends in NCEP atmospheric temperatures (which must also be treated with great caution) that show an increase in the stability of the convective boundary layer as the global temperature has risen over the period. The upper-level negative trends in q are inconsistent with climate-model calculations and are largely (but not completely) inconsistent with satellite data. Water vapor feedback in climate models is positive mainly because of their roughly constant relative humidity (i.e., increasing q) in the mid-to-upper troposphere as the planet warms. Negative trends in q as found in the NCEP data would imply that long-term water vapor feedback is negative—that it would reduce rather than amplify the response of the climate system to external forcing such as that from increasing atmospheric CO2. In this context, it is important to establish what (if any) aspects of the observed trends survive detailed examination of the impact of past changes of radiosonde instrumentation and protocol within the various international networks."


(bolded is mine)

 

Excuse me, this should have been posted before the last post. It's about the commented "ice cores permeability" to CO2 . Error because of this effect is no bigger than +/-100 years.

Timing of Atmospheric CO2 and Antarctic Temperature Changes Across Termination III
Nicolas Caillon, Jeffrey P. Severinghaus, Jean Jouzel, Jean-Marc Barnola, Jiancheng Kang, Volodya Y. Lipenkov
Science magazine. Submitted 25 September 2002; accepted 10 February 2003

http://icebubbles.ucsd.edu/Publications/CaillonTermIII.pdf

Abstract:
"The analysis of air bubbles from ice cores has yielded a precise record of atmospheric greenhouse gas concentrations, but the timing of changes in these gases with respect to temperature is not accurately known because of uncertainty in the gas age–ice age difference. We have measured the isotopic composition of argon in air bubbles in the Vostok core during Termination III (+/-240,000 years before the present). This record most likely reflects the temperature and accumulation change, although the mechanism remains unclear. The sequence of events during Termination III suggests that the CO2 increase lagged Antarctic deglacial warming by 800 +/- 200 years and preceded the Northern Hemisphere deglaciation."

From the text:
"The best correlation (R2 = 0.88) was obtained when we shifted the CO2 profile by 800 +/- 100 years. Combining this uncertainty with the uncertainty introduced by ice accumulation (800 x 0.2, i.e., 160 years),we obtain an overall uncertainty of +/-200 years,indicating that the increase in CO2 lags Antarctic warming by 800 +/- 200 years, which we must consider a mean phase lag because of the method we used to make the correlation."

 

I like how none of these address the fact of rising temps in conjunction with the artificial alterations of the atmospheric chemistry caused by the burning of fossil fuels.

you are attempting to argue a natural process where there is none, what we have is a man made alteration that is causing reactions across the climate system in a way that is unprecedented in the natural climate history. Regardless of what happened in the past what is happening now and what is causing it, is clear.

I understand that you are having trouble grasping the concept of permeability and that you are unwilling to hear an explanation so maybe this article will help you out a bit.

so this study shows; tentatively I might add because this issue is just recently being studied in detail ( article was only just published in 2008 ), that there may be a huge lag in stable co2 samples from ice cores at certain depths and certain temps.

if you want to read the whole article you are welcome to at

http://www.google.com/url?sa=t&source=web&cd=2&ved=0CB4QFjAB&url=http%3A%2F%2Fwww.igsoc.org%2Fjournal%2F54%2F187%2Fj07j102.pdf&rct=j&q=co2%20permiability%20in%20ice%20cores%20&ei=DHxCTL3LEsH98Ab4odwU&usg=AFQjCNF7Q1oTd1Vz7lmrTMwIHgpFnFVs_Q&sig2=IMifZS6lw8zBbnTH8vuytQ

also there is a simple logic that unfortunately escapes most people who argue these glaciations and corresponding co2 levels

Im going to modify something that a denier wrote on another forum who actually had it right but left out a few key components so it would sound like it supported his diatribe

Ice core samples, by definition, must be taken on polar ice caps, because that's the only place where ice stays frozen year-round, and the only place where it can accumulate year after year. But polar ice caps are surrounded by millions of square miles of near-freezing water. Water absorbs carbon dioxide. In fact, the solubility of carbon dioxide in water increases, geometrically, as water temperature decreases, reaching maximum solubility at the freezing point. Of course, this is also true of nitrogen and oxygen, the two primary components of air. However, carbon dioxide is much more soluble than either of those at all temperatures. At the freezing point, carbon dioxide is 30 times more soluble than oxygen and 70 times more soluble than nitrogen. Now, if you have all this very cold, nearly freezing water surrounding these ice caps, sucking up carbon dioxide out of the polar atmosphere, at nearly the highest possible rate, 30 times faster than oxygen, and 70 times faster than nitrogen, doesn't it stand to reason that the air that remains might just have a lot less carbon dioxide in it than the atmosphere across the rest of the planet? This is the air that is being trapped in air bubbles, to be preserved in ice core samples. And it is not representative of the atmosphere as a whole. which is likely to contain higher concentrations of co2. So what happens during a glaciation period is that once things freeze over a wider area and less and less of the co2 is being absorbed by the area in the imediate vicinity of where we take the ice cores then it appears that the co2 level goes up "after" the glaciation whereas in reality it was the local conditions that influence the local levels of co2 that end up trapped in ice bubbles and provide us with sample from which to derive local conditions at the time

this combined with the issue of ice permeability which is only just now being studied is a key factor in why we must remain patient in determining which came first, the chicken or the egg, so to speak in regards to the palio climate, in regards to the alterations we are making in our present atmospheric chemistry the point is kinda moot because we have direct measurements a rising temp in virtual lockstep with rising co2 concentrations.

It was simply a mater of the science catching up to the measurement system, IE not all that wander are lost. Often times once the true complexities are understood similar readings and data sets can reveal entirely different results.

by the way just to show how these time scales have developed one of the first articles to address this issue came up with a time frame of only 10-50 years, since then its grown considerably as the science progresses

if you would like to read the entire article please see
http://www.igsoc.org/annals/10/igs_annals_vol10_year1988_pg141-145.pdf

anyway I could go on but somehow I doubt I'm really getting through to you anyway so believe what you will its the readers I'm primarily interested in and I think they can clearly see that the issue of permeability pretty much precludes any snap decisions concerning the arctic ice records concerning co2

 

It would appear that Boston the Weasel is still posting misinformation. Here is more from the taxpayer supported climate parasites and grant whores at NASA.


http://joannenova.com.au/2010/07/did-giss-discover-30-more-land-in-the-northern-hemisphere/

 

Continuing talking about CO2 and the allegued planet warming due to its greenhouse effect, I want to bring your attention back to my posts 4067, 4071, and 4659

There I posted about Dr. Qing-Bin Lu suggesting that the man-made cause of global warming is not CO2 and the international treaty that saved the planet is not the Kyoto Protocol but the Montreal Protocol of 1987. Rather, says Dr. Lu, the true cause of global warming has been CFCs, or chlorofluorocarbons, once widely used in aerosol cans and refrigeration. As CFC use soared in the decades following World War II, he explains, the globe started warming dramatically. The world stopped warming dramatically when government regulations began to phase out CFCs, an event that culminated in the western world in 2000. Almost immediately afterward, in 2002, the world began to cool as CFCs started to diminish in our atmosphere.

Professor Lu, a path-breaking scientist in the field of ozone protection, made his CO2 discovery by accident — he was looking for culprits in the formation of the ozone hole over Antarctica. A chief suspect was CO2: Climate models produced by climatologists showed that CO2 would have devastating effects on the ozone layer, significantly enlarging the ozone hole over Antarctica and dramatically enlarging it over the Arctic. But when Dr. Lu compared the imagined output of the climate models with the actual measurements taken real-time by satellites and weather balloons, the models turned out to be soaring failures.

“I didn’t see any CO2 effect on temperature or ozone depletion over the South Pole from 1956 to 2008,” explained Dr. Lu, surprised at how totally different the real-world measurements were from those that the climate model predicted. The real-world measurements showed CO2 to be largely irrelevant – “the global warming on Earth’s surface between 1950 and 2000 is pretty much due to CFCs,” he concluded. “The models say that CO2 is a major greenhouse gas but the facts show otherwise.”


This was the then cited paper:
Cosmic-ray-driven electron-induced reactions of halogenated molecules adsorbed on ice surfaces: Implications for atmospheric ozone depletion and global climate change
Qing-Bin Lu, Department of Physics and Astronomy and Departments of Biology and Chemistry, University of Waterloo, Waterloo, ON, N2L 3G1, Canada
Accepted 26 November 2009. editor: S. Peyerimhoff. Available online 3 December 2009.

http://www.sciencedirect.com/scienc...serid=10&md5=f237572f057868ddd1ed15d17ad2037e


Now Dr. Lu has just published another paper on the matter (Journal of Cosmology, June 2010), available in PDF format here:

What is the Major Culprit for Global Warming: CFCs or CO2?

ABSTRACT
"A recent observation strikingly showed that global warming from 1950 to 2000 was most likely caused by the significant increase of chlorofluorocarbons (CFCs) in the Earth atmosphere (Lu, 2010). Here, three key questions are addressed: (1) How could CO2 play a negligible role in recent global warming in view of its extremely high concentrations of ≥300 ppm? (2) Is there other evidence from satellite or ground measurements for the saturation in warming effect of CO2 and other non-CFC gases? And (3) could the greenhouse effect of CFCs alone account for the rise of 0.5~0.6 K in global temperature since 1950? First, the essential feature of the Earth blackbody radiation is elucidated. Then re-analyses of observed data about global temperature change with variations of halocarbons and CO2, the atmospheric transmittance of the infrared radiation and the 1970-1997 change in outgoing longwave radiation spectra of the Earth are presented. It follows by new theoretical calculations of the greenhouse effect of halocarbons. The results strength the conclusion that humans were responsible for global warming in late 20th century, but CFCs, rather than CO2 ,were the major culprit; a long-term global cooling starting around 2002 is expected to continue for next five to seven decades."



P.S.: At RealClimate they made in dec 2008 their last of their usual scorning posts about Dr. Lu's work here: http://www.realclimate.org/index.php/archives/2008/12/ozone-holes-and-cosmic-rays/ No new posts on this matter since then.

 

From the last Lu's paper:

5. Concluding remarks
In comparison with previous calculations on the greenhouse effect of CFCs, the present calculations give rise to a larger greenhouse effect. This is due to two factors: the former calculations significantly underestimated the amplification factor of water vapor feedbacks by using a much smaller β value of 0.15 (Ramanathan, 1975) and also overestimated the greenhouse effect of CO2 by assuming a logarithmical increase in radiative forcing of CO2 with increasing concentration (Ramanathan et al., 1985, 1998; IPCC, 2001, 2007). These should be revised with the present observations.

It should be noted that the application of the CO2-palaeoclimate relation to the recent anthropogenic warming is questionable. Some studies reviewed in the IPCC Reports (2001, 2007) showed that CO2 co-varied with Antarctic temperature over glacial-interglacial cycles, suggesting a close link between CO2 variation and temperature. Ice core records, however, indicate that the rise in atmospheric CO2 is the effect rather than the cause of surface warming in palaeoclimate. For instance, a rapid rise by 5 °C in global average sea surface temperature occurred during transitions from the last Glacial Maximum to the onset of Holocene times; detailed ice core studies by Smith et al. (1999) found that the concentration of atmosphere CO2 increased by about 80 ppm (from ~190 to 270 ppm). But the latter was due to the effect of the rise in global surface temperature on driving more CO2 emission predominantly from the ocean (Smith et al., 1999). If one reversed the sequence and took the CO2 increase as the cause of the 5 °C rise in global surface temperature, then it would be extremely difficult to understand why no global temperature increases were observed for the increases of atmospheric CO2 from 285 to 308 ppm and 310 to 330 ppm in the decades from 1850 to 1930 and 1950 to 1975, respectively. In fact, high-resolution ice core records of temperature proxies and CO2 during deglaciations generally show that Antarctic temperature started to rise about one thousand years before the rise of atmospheric CO2, as well observed by Fischer et al. (1999), Veizer et al. (2000), Caillon et al. (2003) and Stott et al. (2007). And despite strongly decreasing temperatures, high CO2 concentrations can be sustained for thousands of years during glaciations (Fischer et al., 1999). These facts indicate that atmospheric CO2 was not the main cause of these climate transitions (Smith et al., 1999; Fischer et al., 1999; Veizer et al., 2000; Caillon et al., 2003; Stott et al., 2007).

Finally, accurate and reliable analysis of satellite datasets are often affected by the climate models that investigators use. This is to some extent caused by the complexity of the scientific issue, which might require the use of a certain climate model to guide the data analysis. On the other hand, researchers should also be aware of the fact that used climate models may be incorrect or incomplete. An open opinion about different models may be instrumental in revealing the truth. This study did not aim to make precise calculations of global temperature change with a sophisticated climate model including multiple parameters and factors. But it does show that the warming effect of CO2 and other non-CFC gases had most likely saturated and CFCs and HCFCs could account for global warming observed in the late 20th century. A long-term global cooling starting around 2002 is expected to continue for next five to seven decades.

(bolded is mine)

 

Here a link to Dr. Lu's selected publications and conference presentations:

http://www.science.uwaterloo.ca/~qblu/publications.html


Just to avoid the usual idiotic commentaries about Big-Oil and the like, Dr. Lu's fundings come from:

Ontario’s Ministry of Research and Innovation (Dr. Lu was recently receiving an Early Researcher Award)

Canadian Institutes of Health Research (CIHR)

Natural Sciences and Engineering Research Council of Canada (NSERC)

Canada Foundation of Innovation (CFI)

Ontario Innovation Trust (OIT)

University of Waterloo