Guest essay by Richard Taylor
Our current understanding climate was influenced profoundly by the publication (J.R. Petit, et al., 1999) of deuterium (2H) measurements from metre 8 to metre 3310 of the Vostok ice-core, indicating the temperature of the nearby atmosphere from 1800 to 421000 BC. Some authorities claim, and many believe, that unprecedented climate-change has begun in recent years which threatens the very existence of human-kind. The uppermost 7 m of the Vostok core might have provided a unique perspective on this frightening claim, but the available data (https://www.ncdc.noaa.gov/paleo/study/2453) have only a mean deuterium value of -438 ‰ for this recent portion, well below the highest value in the core of -414.8 ‰.
A Russian team, however, has been active establishing a chronology of deuterium from snow-cores and -pits near the Vostok station (A.A. Ekaykin, et al., 2014). A summary (www.ncdc.noaa.gov/paleo/study/22532) with digital data became available in May, 2017. The data include annual measurements from 1654 to 2010, providing an overlap with the ice-core record that enables an assessment of present conditions from the perspective of ice-core record.
Comparison of ice-core and snow-core/pit records
The following graph shows the deuterium fractions of the Vostok ice-core sections dated 1669, 1692, 1716, 1737, 1760, 1780 and 1801. These correspond to the years 1658 through 1811 of the snow-core/pit record. Ice-core deuterium appears to be a little higher than snow deuterium, and the average for the 7 ice-core sections is 2.92 ‰ greater than the average for the 155 corresponding years of compiled snow samples.
The deuterium scale on graphs in this note is annotated in 9 ‰ intervals, as 9 ‰ / ⁰C is the basic deuterium/temperature conversion factor for the Vostok core quoted by Petit (ibid.).
Present Values in Perspective
Each core-section in the overlap interval spans 20 to 23 years, and their deuterium values show much less variability than the annual values of snow. For comparability in the following graph, the snow values were averaged into 20-year groups, with the exception of the earliest (1654 to 1680) 26-year group. Each average was adjusted upward by 2.92 ‰ as suggested by the overlap comparison.
The chart shows Vostok ice-core deuterium, along with the adjusted snow-averages, for a detailed indication of temperature from -140000 (140000 BC) to 2000. Features in the chart are the cold end of a glaciation (-139000), warming to the second-highest thermal peak in the Vostok record (-416.3 ‰ at -127374), episodic but general cooling into glaciation with the lowest value in the record of -488.3 ‰ at -22413, warming through the Younger Dryas reversal (-11000) to the Holocene Optimum (-9200), then modest but variable cooling to the present.
Carbon-dioxide (CO2) measurements from air-inclusions in the cores from the Vostok (Petit, ibid.), Taylor Dome (A. Indermühle, et al., 1999) and Law Dome (D.M. Etheridge, et al. 1996) ice cores as well as from surface air at the South Pole (C.D. Keeling, et al., 2001) provide a record of CO2 in regional air from -412000 to 2000. The chart shows the portion from -140000.
To the year -6000, changes in CO2 lag proportional changes in deuterium. The lag tends to be shortest at lower values of deuterium and CO2 and longest after thermal peaks. For example, the chart shows that the decline in CO2 from -117000 to -104000 follows a proportional decline in deuterium that occurred about 9000 years earlier. Modern climate-science contends that CO2 is a powerful greenhouse gas that controls atmospheric temperature. Since cause must precede effect, lag shows that CO2 above the minimum level of 180 ppm in the Vostok record has no significant effect on temperature.
From -6000 on, CO2 began to rise to concentrations far beyond any seen previously in the ice-core record. The lack of any corresponding rise in deuterium over the last 8000 years indicates, again, the lack of effect that CO2 has on atmospheric temperature.
Snow at Vostok from 1990-2010 has an adjusted deuterium value of -433.7 ‰. This is 18.9 ‰ below the highest value that is for a core section representing 219 years. It is 54.6 ‰ above the lowest value that is for a core section representing 91 years. Thus, from the Vostok perspective, our present climate is about 2 ⁰C below the warmest of the last 420000 years, and about 6 ⁰C above the coldest.
General CO2-lag in ice-core records and the lack of warming over the last 8000 years of extraordinary increase in CO2 show that the hypothesis of significant warming of the atmosphere by CO2 over the last century is absurd. Attribution of derivative effects (i.e. “climate change”) to CO2 is, therefore, ridiculous. These fictions, the dire prophecies that attend them and the disparagement of those that question them, however, are vigorously promoted and widely accepted. They seem to be as important socially as they are false scientifically.
While recent snow at Vostok adds to the falsification of the hypothesis of “dangerous man-made climate change by carbon-dioxide, a powerful heat-trapping greenhouse-gas”, such falsification was evident in the ice-core data published in 1999 and has always been logically obvious to anyone with an understanding of the carbon cycle at the surface of the earth.
For distraction from abuse by the saviors of planets, polar bears, putative grandchildren, etc., those of us with some affection for natural science might consider what news from Vostok (or Dome Fuji or Dome C) would indicate that climate might be trending beyond the limits of the last 400000 years. Speaking personally, I would be surprised to see a 20-year average of 2H or 18O in precipitation beyond the range of the ice-core record.
Ekaykin, A.A.; Kozachek, A.V.; Lipenkov, V.Ya.; Shibaev, Yu.A. 2014. Multiple climate shifts in the Southern Hemisphere over the past three centuries based on central Antarctic snow pits and core studies. Annals of Glaciology, 55(66), 259-266. doi: 10.3189/201AoG66A189
Etheridge, D.M., L.P. Steele, R.L. Langenfelds, R.J. Francey, J-M. Barnola, and V.I. Morgan. 1996. Natural and anthropogenic changes in atmospheric CO2 over the last 1000 years from air in Antarctic ice and firn. Journal of Geophysical Research 101:4115-4128.
Indermühle, A., T.F. Stocker, F. Joos, H. Fischer, H.J. Smith, M. Wahlen, B. Deck, D. Mastroianni, J. Tschumi, T. Blunier, R. Meyer, B. Stauffer. 1999. Holocene carbon-cycle dynamics based on CO2 trapped in ice at Taylor Dome, Antarctica. Nature 398:121-126.
Keeling, C.S., S. C. Piper, R. B. Bacastow, M. Wahlen, T. P. Whorf, M. Heimann, and H. A. Meijer, Exchanges of atmospheric CO2 and 13CO2 with the terrestrial biosphere and oceans from 1978 to 2000. I. Global aspects, SIO Reference Series, No. 01-06, Scripps Institution of Oceanography, San Diego, 88 pages, 2001.
Petit, J.R., J. Jouzel, D. Raynaud, N.I. Barkov, J.M. Barnola, I. Basile, M. Bender, J. Chappellaz, J. Davis, G. Delaygue, M. Delmotte, V.M. Kotlyakov, M. Legrand, V. Lipenkov, C. Lorius, L. Pépin, C. Ritz, E. Saltzman, and M. Stievenard. 1999. Climate and atmospheric history of the past 420,000 years from the Vostok Ice Core, Antarctica. Nature 399:429-436.