- Regional sensitivity of Greenland precipitation to NAO variability
E. Mosley-Thompson, C. R. Readinger, P. Craigmile, L. G.
Thompson and C. A. Calde.
Geophysical Research Letters, Vol. 32, 20 Dec 2005.
- Testing the fidelity of methods used in proxy-based reconstructions of past climate
Michael E. Mann, Scott Rutherford, Eugene Wahl and Caspar Amann.
Journal of Climate, Vol. 18, No. 20, 15 Oct 2005, pp. 4097-4107.
Two widely used statistical approaches to reconstructing past climate histories from climate "proxy" data such as tree rings, corals, and ice cores are investigated using synthetic "pseudoproxy" data derived from a simulation of forced climate changes over the past 1200 yr. These experiments suggest that both statistical approaches should yield reliable reconstructions of the true climate history within estimated uncertainties, given estimates of the signal and noise attributes of actual proxy data networks.
- Climate over past millennia
P. D. Jones and M. E. Mann.
Reviews of Geophysics, Vol. 42, No. 2, May 2004
We review evidence for climate change over the past several millennia from instrumental and high-resolution climate 'proxy' data sources and climate modeling studies. We focus on changes over the past 1 to 2 millennia. We assess reconstructions and modeling studies analyzing a number of different climate fields, including atmospheric circulation diagnostics, precipitation, and drought. We devote particular attention to proxy-based reconstructions of temperature patterns in past centuries, which place recent large-scale warming in an appropriate longer-term context. Our assessment affirms the conclusion that late 20th century warmth is unprecedented at hemispheric and, likely, global scales. There is more tentative evidence that particular modes of climate variability, such as the El Nino/Southern Oscillation and the North Atlantic Oscillation, may have exhibited late 20th century behavior that is anomalous in a long-term context. Regional conclusions, particularly for the Southern Hemisphere and parts of the tropics where high-resolution proxy data are sparse, are more circumspect. The dramatic differences between regional and hemispheric/global past trends, and the distinction between changes in surface temperature and precipitation/drought fields, underscore the limited utility in the use of terms such as the 'Little Ice Age' and 'Medieval Warm Period' for describing past climate epochs during the last millennium. Comparison of empirical evidence with proxy-based reconstructions demonstrates that natural factors appear to explain relatively well the major surface temperature changes of the past millennium through the 19th century (including hemispheric means and some spatial patterns). Only anthropogenic forcing of climate, however, can explain the recent anomalous warming in the late 20th century.
- Microparticle record in the Guliya ice core and its comparison with polar records since the last interglacial
Wu Guangjian, Yao Tandong, L. G. Thompson and Li Zhongqin.
Chinese Science Bulletin, Vol. 49, No. 6, Mar 2004, pp. 607-611.
Based on the study of oxygen isotope and microparticle in the Guliya ice core, atmospheric dust and environmental changes in the northwest Tibetan Plateau since the last interglacial were revealed. The microparticle record indicates that low dust load on the Plateau in the interglacial. Particle concentration increased rapidly when the climate turned into the last glacial and reached the maximum during the MIS 4. In the Last Glacial Maximum, however, the enhancement of microparticle concentration was slight, differing to those in the Antarctic and Greenland. On the orbital timescale, both the temperature on the Tibetan Plateau and summer solar insolation in the Northern Hemisphere had their impact on the microparticle record, but the difference in phase and amplitude also existed. Though having the same dust source, microparticle records in the ice cores on the Tibetan Plateau and the Greenland seem to have different significance.
- Spatially and seasonally-specific responses to forcing as detected in paleoclimate reconstructions of past centuries; Geological Society of America, Northeastern Section, 38th annual meeting; Geological Society of America, Southeastern Section, 53rd annual meeting
Michael E. Mann.
Abstracts with Programs - Geological Society of America, Vol. 36, No. 2, Mar 2004, pp. 150.
I will review recent progress in proxy-based reconstruction and modeling of climate changes in past centuries. Seasonally and spatially-resolved empirical surface temperature reconstructions of past centuries will be discussed, with an emphasis on the seasonal and spatial details of estimated changes. These details will be discussed and interpreted in the context of the modeled seasonal and regional response to estimated radiative forcing changes in past centuries. The likely role of radiatively forced changes in the NAO and the El Nino/Southern Oscillation will be discussed.
- NAO signal recorded in the stable isotopes of Greenland ice cores
B. M. Vinther, S. J. Johnsen, K. K. Andersen, H. B. Clausen and A. W. Hansen.
Geophysical Research Letters, Vol. 30, No. 7, Apr 2003
The winter delta super(18)O signal is extracted from 7 Greenland ice cores covering the past ~700 years. To filter out noise and local variations in the 7 isotope records a principal component analysis is carried out on the ice core data. A comparison between the time series of the first principal component (PC1) with 67 years of winter (December to March) temperature measurements from 3 southern Greenland synoptic stations shows highly significant correlations. Southern Greenland winter temperatures are known to be greatly influenced by the North Atlantic Oscillation (NAO). A good proxy for southern Greenland temperatures is therefore expected to reveal at least parts of the NAO signal. It is shown that the PC1 time series indeed is significantly correlated to the NAO during the winter months. The inclusion of ice core winter season delta super(18)O time series in future multiproxy NAO reconstructions is therefore recommended.
- Tropical Glacier and Ice Core Evidence of Climate Change on Annual to Millennial Time Scales
L. G. Thompson, E. Mosley-Thompson, M. E. Davis, P. Lin, K. Henderson and T. A. Mashiotta.
Climatic Change, Vol. 59, No. 1-2, Jul 2003, pp. 137-155.
This paper examines the potential of the stable isotopic ratios, super(18)O/ super(16)O ( delta super(18)O sub(ice)) and super(2)H/ super(1)H ( delta D sub(ice)), preserved in mid to low latitude glaciers as a tool for paleoclimate reconstruction. Ice cores are particularly valuable as they contain additional data, such as dust concentrations, aerosol chemistry, and accumulation rates, that can be combined with the isotopic information to assist with inferences about the regional climate conditions prevailing at the time of deposition. We use a collection of multi-proxy ice core histories to explore the delta super(18)O-climate relationship over the last 25,000 years that includes both Late Glacial Stage (LGS) and Holocene climate conditions. These results suggest that on centennial to millennial time scales atmospheric temperature is the principal control on the delta super(18)O sub(ice) of the snowfall that sustains these high mountain ice fields. Decadally averaged delta super(18)O sub(ice) records from three Andean and three Tibetan ice cores are composited to produce a low latitude delta super(18)O sub(ice) history for the last millennium. Comparison of this ice core composite with the Northern Hemisphere proxy record (1000-2000 A.D.) reconstructed by Mann et al. (1999) and measured temperatures (1856-2000) reported by Jones et al. (1999) suggests the ice cores have captured the decadal scale variability in the global temperature trends. These ice cores show a 20th century isotopic enrichment that suggests a large scale warming is underway at low latitudes. The rate of this isotopically inferred warming is amplified at higher elevations over the Tibetan Plateau while amplification in the Andes is latitude dependent with enrichment (warming) increasing equatorward. In concert with this apparent warming, in situ observations reveal that tropical glaciers are currently disappearing. A brief overview of the loss of these tropical data archives over the last 30 years is presented along with evaluation of recent changes in mean delta super(18)O sub(ice) composition. The isotopic composition of precipitation should be viewed not only as a powerful proxy indicator of climate change, but also as an additional parameter to aid our understanding of the linkages between changes in the hydrologic cycle and global climate.
- Indian monsoon and North Atlantic Oscillation signals reflected by Cl super(-) and Na super(+) in a shallow ice core from Dasuopu glacier, Xixabangma, Himalaya
Ninglian Wang, Tandong Yao, L. G. Thompson and M. E. Davis.
Annals of Glaciology, 273-277. 2002, pp. Vol. 35, p.
Information about past atmospheric circulation and climate change can be revealed by the chemical constituents of ice cores. Based on the analytical results of Cl super(-) and Na super(+) concentrations in an 18.5 m ice core, which contains 14 annual layers, from the Dasuopu glacier, central Himalaya, a significant correlation is found between Cl super(-) and Na super(+) concentrations. This, along with the average Cl super(-)/Na super(+) weight ratio of 1.9, indicates that moisture at the drilling site came mostly from oceans. Furthermore, there was a high positive correlation between the Cl super(-)/Na super(+) ratio in the summer monsoon layers and the monsoon rainfall in northeast India, and there exists a teleconnection between the Cl super(-) and Na super(+) concentrations in this shallow ice core and the North Atlantic Oscillation.
- Kilimanjaro Ice Core Records: Evidence of Holocene Climate Change in Tropical Africa
L. G. Thompson, E. Mosley-Thompson and M. E. Davis, et al.
Science (Washington), Vol. 298, No. 5593, 18 Oct 2002, pp. 589-593.
Six ice cores from Kilimanjaro provide an similar to 11.7-thousand-year record of Holocene climate and environmental variability for eastern equatorial Africa, including three periods of abrupt climate change: similar to 8.3, similar to 5.2, and similar to 4 thousand years ago (ka). The latter is coincident with the "First Dark Age," the period of the greatest historically recorded drought in tropical Africa. Variable deposition of F super(-) and Na super(+) during the African Humid Period suggests rapidly fluctuating lake levels between similar to 11.7 and 4 ka. Over the 20th century, the areal extent of Kilimanjaro's ice fields has decreased similar to 80%, and if current climatological conditions persist, the remaining ice fields are likely to disappear between 2015 and 2020.
- Temperature and methane records over the last 2 ka in Dasuopu ice core
Tandong Yao, L. G. Thompson and Keqin Duan, et al.
Science in China Series D (Earth Sciences), Vol. 45, No. 12, Dec 2002, pp. 1068-1074.
High resolution delta super(18)O and methane records over the last 2ka have been reconstructed from Dasuopu ice core recovered from the Himalayas. Analysis shows that the delta super(18)O record correlates well with the Northern Hemispheric temperature, Dunde ice core record, and with temperature record in eastern China. The warming trend detected in delta super(18)O record from the last century is similar to that during the Medieval warm period. There is a dramatic increasing in methane concentration in the Dasuopu ice core, which reached 1031 nmol times mol super(-1) in 1997. Moreover, methane concentration in the Dasuopu ice core is about 15%-20% higher than that in Antarctica and Greenland. There is a positive correlation between methane concentration and delta super(18)O in Dasuopu ice core.
- A three thousand year record of North Atlantic climate
C. J. Proctor, A. Baker and W. L. Barnes.
Climate Dynamics, Vol. 19, No. 5-6, Aug 2002, pp. 449-454.
Annual band counting on three radiometrically dated stalagmites from NW Scotland, provides a record of growth rate variations for the last 3000 years. Over the period of instrumental meteorological records we have a good historical calibration with local climate (mean annual temperature/mean annual precipitation), regional climate (North Atlantic Oscillation) and sea surface temperature (SST; strongest at 65-70 degree N, 15-20 degree W), although the correlation with the latter breaks down prior to the instrumental record. This suggests that the climatic factors that force NW Scottish climate and therefore our stalagmite growth varied through time, and include winter NAO strength, the strength of the thermohaline circulation and possibly solar output. Spectral analysis was performed on the stalagmite growth rate time series. A spectral frequency of 50-70 years is predominant in two stalagmites that were deposited from 1000 to 3000 BP; a slightly longer frequency of 72-94 years is dominant from 1000 BP to present. These are the same as that observed in ocean GCM output for the North Atlantic region SSTs. Our stalagmites provide high resolution, precisely dated evidence of a similar periodicity predominating over the last 3000 years in a climate proxy record known to be sensitive to changes in forcing functions relevant to the North Atlantic sector.
- The Value of Multiple Proxies
M. E. Mann.
Science (Washington), Vol. 297, No. 5586, 30 Aug 2002, pp. 1481-1482.
Reconstructions of Northern Hemisphere (NH) temperatures in past centuries provide evidence that the warming of the late 20th century is unprecedented in at least the past millennium. But how are these reconstructions obtained? And how reliable are they? Widespread, direct instrumental measurements of surface temperature are available only for the past hundred years or so. Indirect or "proxy" indicators of climate variability must therefore be used to reconstruct earlier changes. To ensure their reliability, reconstructions based on these proxies must be validated by comparison with instrumental records during periods of overlap.
- A Well-Verified, Multiproxy Reconstruction of the Winter North Atlantic Oscillation Index since 1400
E. R. Cook, R. D. D'Arrigo and M. E. Mann.
Journal of Climate, Vol. 15, No. 13, Jul 2002, pp. 1754-1764.
A new, well-verified, multiproxy reconstruction of the winter North Atlantic Oscillation (NAO) index is described that can be used to examine the variability of the NAO prior to twentieth century greenhouse forcing. It covers the period 1400-1979 and successfully verifies against independent estimates of the winter NAO index from European instrumental and noninstrumental data as far back as 1500. The best validation occurs at interannual timescales and the weakest at multidecadal periods. This result is a significant improvement over previous proxy-based estimates, which often failed to verify prior to 1850, and is related to the use of an extended reconstruction model calibration period that reduced an apparent bias in selected proxies associated with the impact of anomalous twentieth century winter NAO variability on climate teleconnections over North Atlantic sector land areas. Although twentieth century NAO variability is somewhat unusual, comparable periods of persistent positive-phase NAO are reconstructed to have occurred in the past, especially before 1650.
- Extending North Atlantic Oscillation reconstructions back to 1500
J. Luterbacher, E. Xoplaki and D. Dietrich, et al.
Atmospheric Science Letters, Vol. 2, No. 1-4, Jun 2001, pp. 114-124.
Monthly (1659-1995) and seasonal (1500-1658) North Atlantic Oscillation (NAO) indices were estimated using instrumental and documentary proxy predictors from Eurasia. Uncertainty estimates were calculated for the reconstructions, and the variability of the 500-year winter NAO has been assessed. The late twentieth century NAO extremes are within the range of variability during earlier centuries.
- Reconstruction of the North Atlantic Oscillation, 1429-1983
M. F. Glueck and C. W. Stockton.
International Journal of Climatology, Vol. 21, No. 12, Oct 2001, pp. 1453-1465.
The North Atlantic Oscillation (NAO) is considered to be the dominant mode of winter atmospheric variability in the Northern Hemisphere (Barnston AG, Livezey RE. 1987. Classification, seasonality and persistence of low frequency atmospheric circulation patterns. Monthly Weather Review 115: 1083-1126), especially in the North Atlantic region. A better understanding of its recent variability in the context of pre-instrumental period variations is critical for prediction purposes. A 555-year (1429-1983) multi-proxy reconstruction of the cool season NAO, calibrated against the Lisbon-Iceland (LISJHI) NAO, is presented. Predictor variables include tree-ring chronologies from Morocco and Finland, GISP2 delta super(18)O annual series, and a GISP2 snow accumulation record. Although the reconstructed values are generally lower than the instrumental values during the calibration period (1863-1983), the final reconstruction does capture the low frequency of the instrumental NAO. The reconstruction compares favourably with existing shorter NAO reconstructions and with the instrumental NAO. The variability in the reconstructed NAO is also discussed within the context of lengthy regional climate records. Results suggest that the occurrence and length of the recent persistently high phase of the NAO are not unusual over the 555-year period of time, but that the magnitude of some of the instrumental values may, in fact, be unique.
- Ice core evidence for climate change in the tropics; implications for our future; Past global changes and their significance for the future
Lonnie G. Thompson.
Quaternary Science Reviews, Vol. 19, No. 1-5, Jan 2000, pp. 19-35.
- Ice-core palaeoclimate records in tropical South America since the last glacial maximum; Quaternary climate change and South America; a tribute to Chalmers Clapperton
Lonnie G. Thompson, Ellen Mosley-Thompson and Keith A. Henderson.
JQS.Journal of Quaternary Science, Vol. 15, No. 4, May 2000, pp. 377-394.
- Indian monsoon signals reflected by the ratio of Cl (super -) to Na (super +) in Dasuopu ice core from Xixiabangma, Himalayas; The 15th Himalayan-Karakoram-Tibet workshop; study of the Qinghai-Tibet Plateau in the new century
Wang Ninglian, Yao Tandong and Pu Jianchen, et al.
Dixue Qianyuan = Earth Science Frontiers, Vol. 7, Apr 2000,
- New evidence for enhanced cosmogenic isotope production rate in the atmosphere nearly equal 37 kaBP from the Guliya ice core
Wang Ninglian, Yao Tandong and Qin Dahe, et al.
Chinese Science Bulletin, Vol. 44, No. 17, Sep 1999, pp. 1616-1620.
A (super 36) Cl peak was found in the predicted section of Guliya ice core, from the Qinghai-Tibetan Plateau, at about 37 kaBP. This cannot be interpreted by means of changes in the accumulation rate, but by the enhanced cosmogenic isotope production rate in the atmosphere. Compared with the records of (super 10) Be and (super 36) Cl in the other regions, the peaks of the cosmogenic isotopes are global and can be considered as time marks. An intriguing fact is that the peaks coincided with cold periods.
- Paleoclimatology: Reconstructing Climates of the Quaternary
Raymond S. Bradley.
Amherst: University of Massachusetts, 1999.
- The Pinatubo eruption in South Pole snow and its potential value to ice-core paleovolcanic records
Jihong Cole-Dai and Ellen Mosley-Thompson.
Annals of Glaciology, Cambridge, United Kingdom, Vol. 29,
1999, pp. 99-105.
Snow samples collected in the 1996 austral summer at South Pole show that sulfate concentrations in snow and, by inference, sulfur aerosol concentrations in the Antarctic atmosphere were elevated from the end of 1991 to mid-1994 over a stable, non-volcanic background. The new data support earlier findings that the June 1991 Pinatubo eruption and the Hudson eruption in the same year deposited volcanic sulfate and tephra in South Pole snow, and provide strong evidence of the global distribution of volcanic materials from the Pinatubo eruption. In this study, snow samples were taken in six snow pits spatially distributed around the South Pole station in order to evaluate the local spatial variability of volcanic signals due to glaciological variables such as snow-accumulation rates and snow redistribution by wind after initial deposition. The results indicate that Pinatubo sulfate flux varies by as much as 20% throughout a 400 km super(2) area centered around the South Pole station. This glaciological variability probably represents the likely range of volcanic signals due to variations in snow deposition and post-depositional changes. The Pinatubo eruption provides an unprecedented opportunity to estimate aerosol mass loadings by explosive volcanic eruptions found in Antarctic ice cores via a quantitative relationship between aerosol mass loadings and sulfate flux in Antarctic snow. Here the satellite-estimated Pinatubo SO sub(2) emission and the measured volcanic sulfate flux in snow, with an assumed linearly quantitative relationship, are used to calculate SO sub(2) loadings for several well-known volcanic eruptions in the past 300 years covered by a shallow (42 m) South Pole firn core drilled in 1996. The errors for the calculated mass loadings are estimated by means of the glaciological variability associated with Pinatubo volcanic flux.
- Reconstruction of monthly NAO and EU indices back to AD 1675
Juerg Luterbacher, Christoph Schmutz, Dimitrios Gyalistras, Eleni Xoplaki and Heinz Wanner.
Geophysical Research Letters, Washington, DC, Vol. 26, No. 17, 1999, pp. 2745-2748.
Instrumental station pressure, temperature and precipitation measurements and proxy data were used to statistically reconstruct monthly time series of the North Atlantic Oscillation (NAO) and the Eurasian (EU) circulation indices back to 1675. Systematic testing of the reconstruction procedure indicated generally reliable reconstructions throughout the entire period, except for summertime before about 1750. Predictive skill varied for different sub-periods depending on data availability. It was highest for autumn and winter and was generally better for the EU than for the NAO index. Wavelet analysis suggested significant low-frequency variability, especially for the spring, summer and annual averaged indices. The co-variability between the NAO and EU indices was found to exhibit large decadal to century timescale variations, indicating that climate variability over the continent is temporarily decoupled from the NAO.
- Concentration of nitrate in the Guliya ice core from the Qinghai-Xizang Plateau and the solar activity
Wang Ninglian, Yao Tandong and L. G. Thompson.
Chinese Science Bulletin, Vol. 43, No. 10, May 1998, pp. 841-844.
The variations of NO (super -) (sub 3) concentration in the Guliya ice core are reconstructed for recent about 1000 a. Spectrum analysis of NO (super -) (sub 3) indicates significant periodicities in the variations of NO (super -) (sub 3) concentration, which coincide with the periodicities of the solar activity. Therefore, a positive correlation between the variations of NO (super -) (sub 3) concentration and the solar activity is found.
- "The delta (super 18) O record along the Greenland Ice Core Project deep ice core and the problem of possible Eemian climatic instability"
Greenland Summit ice cores; Greenland Ice Sheet Project 2, Greenland Ice Core Project
Sigfus J. Johnsen, Henrik B. Clausen and Willi Dansgaard, et al.
United States (USA): American Geophysical Union, Washington, DC, United States (USA),
- The North Atlantic Oscillation and its imprint on precipitation and ice accumulation in Greenland
C. Appenzeller, J. Schwander, S. Sommer and T. F. Stocker.
Geophysical Research Letters, Washington, DC, Vol. 25, No. 11, 1998, pp. 1939-1942.
Interannual to decadal fluctuations in net precipitation and ice accumulation are examined over Greenland. It is shown that in western Greenland these fluctuations are correlated with the North Atlantic Oscillation. The analysis is based on two complementary data sources: A highly resolved net precipitation and accumulation history over 15 years derived from the reanalysis data of the European Centre for Medium-Range Weather Forecasts and a composite ice accumulation record representative for the western part of Central Greenland. It is suggested that western Greenland snow accumulation is a good proxy for the NAO index with the potential for the reconstruction of a long time series.
- North Atlantic oscillation dynamics recorded in Greenland ice cores
C. Appenzeller, T. F. Stocker and M. Anklin.
Science, Washington, DC, Vol. 282, No. 5388, 1998, pp. 446-449.
Carefully selected ice core data from Greenland can be used to reconstruct an annual proxy North Atlantic oscillation (NAO) index. This index for the past 350 years indicates that the NAO is an intermittent climate oscillation with temporally active (coherent) and passive (incoherent) phases. No indication for a single, persistent, multiannual NAO frequency is found. In active phases, most of the energy is located in the frequency band with periods less than about 15 years. In addition, variability on time scales of 80 to 90 years has been observed since the mid-19th century.
- "Validity of the temperature reconstruction from water isotopes in ice cores"
Greenland Summit ice cores; Greenland Ice Sheet Project 2, Greenland Ice Core Project
Jean Jouzel, R. B. Alley and K. M. Cuffey, et al.
United States (USA): American Geophysical Union, Washington, DC, United States (USA),
- The Eem stable isotope record along the GRIP ice core and its interpretation; Last interglaciation in the Arctic and subarctic regions; selected papers from the second LIGA symposium
Sigfus J. Johnsen, Henrik B. Clausen, Willi Dansgaard, Niels S. Gundestrup, Claus U. Hammer and Henrik Tauber.
Quaternary Research (New York), Vol. 43, No. 2, Mar 1995, pp. 117-124.
- Greenland palaeotemperatures derived from GRIP bore hole temperature and ice core isotope profiles
Sigfus J. Johnsen, Dorthe Dahl-Jensen, Willi Dansgaard and Niels Gundestrup.
Tellus.Series B: Chemical and Physical Meteorology, Stockholm, Sweden, Vol. 47B, No. 5, 1995, pp. 624-629.
Modeling the temperature profile along the GRIP deep bore at the summit of the Greenland ice sheet leads to conversion factors that allow interpretation of the dated stable isotope profile as a climatic temperature record spanning the last 113,000 years. When corrected for surface elevation changes, the late glacial to Boreal temperature shift appears to have been 22 degrees C in central Greenland. The warming at the end of the last glaciation probably began earlier in Greenland, than in Antarctica.
- "Paleoenvironmental conditions in Antarctica since A.D. 1500; ice core evidence"
Climate since A.D. 1500
United States (USA): Routledge, New York, NY, United States (USA),
1995Ice core evidence indicating paleoenvironmental condition in Antarctica since 1500 A.D. is presented. Ice cores were dated using Delta (super 18) O. Ice core records are described from six research stations. Surface temperatures from the Antarctic Peninsula are presented from the 1900s and annual variations are evaluated. Dust concentration deviations from Siple Station and South Pole Station are compared. This research is applied to global climate change studies.(MTE)
- Climate of the last 500 years; high resolution ice core records; Decadal to millennial-scale variability in the climate system
E. Mosley-Thompson, L. G. Thompson, J. Dai, M. Davis and P. N. Lin.
Quaternary Science Reviews, Vol. 12, No. 6, 1993, pp. 419-430.
- Evidence for general instability of past climate from a 250-kyr ice-core record
W. Dansgaard, S. J. Johnsen and H. B. Clausen, et al.
Nature (London), Vol. 364, No. 6434, 15 Jul 1993, pp. 218-220.
- Irregular glacial interstadials recorded in a new Greenland ice core
S. J. Johnsen, H. B. Clausen and W. Dansgaard, et al.
Nature (London), Vol. 359, No. 6393, 24 Sep 1992, pp. 311-313.
- "Reconstructing interannual climate variability from tropical and subtropical ice-core records"
El Nino; historical and paleoclimatic aspects of the Southern Oscillation
L. G. Thompson, E. Mosley-Thompson and P. A. Thompson.
United Kingdom (GBR): Cambridge University Press, Cambridge, United Kingdom (GBR),
- Resolving abrupt and high-frequency global changes in the ice-core record; Global changes of the past
Hans Oeschger and Anne Arquit.
1989 OIES Global Change Institute, Snowmass, CO
- CO (sub 2) record in the Byrd ice core 50,000-5,000 years BP
A. Neftel, H. Oeschger, T. Staffelbach and B. Stauffer.
Nature (London), Vol. 331, No. 6157, 18 Feb 1988, pp. 609-611.
- Information on past solar activity and geomagnetism from (super 10) Be in the Camp Century ice core
J. Beer, U. Siegenthaler and G. Bonani, et al.
Nature (London), Vol. 331, No. 6158, 25 Feb 1988, pp. 675-679.
- The origin of Arctic precipitation as deduced from its deuterium excess; Proceedings of the Symposium on ice-core analysis
J. White, S. J. Johnsen, W. Dansgaard and B. (convener) Messerli.
Annals of Glaciology, Vol. 10, 1988, pp. 219-220.
- Shallow-core analysis and pit studies at Siple Station, Antarctica; implications for extraction of a 500 year proxy climate record; Proceedings of the Symposium on ice-core analysis
E. Mosley-Thompson, L. G. Thompson, J. F. Paskievitch, P. M. Grootes and B. (convener) Messerli.
Annals of Glaciology, Vol. 10, 1988, pp. 212.
- Accelerator mass spectrometry and ice core research; Accelerator mass spectrometry; proceedings of the Fourth international symposium
Nuclear Instruments & Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms, Vol. B29, No. 1-2, 1987, pp. 196-202.
- Results of a survey conducted by the Ice Core Working Group.
Paul A. Mayewski, Randy Borys and Thomas Crowley, et al.
United States (USA): University of New Hampshire, Institute for the Study of Earth, Oceans and Space, Glacial Research Group, Durham, NH, United States (USA), 1987,
This report summarizes results of a survey conducted by the Ice Core Working Group (ICWG). In 1986 the Committee on Glaciology of the National Academy of Sciences initiated the work leading to Recommendations for a U.S. Ice Coring Program which eventually resulted in the formation of the Ice Core Working Group (ICWG). As part of the major tasks of the ICWG, a questionnaire was handed out to the ice core community in order to assess the breadth and capability in the field. The questionnaire dealt with eight disciplines in the physical and geophysical sciences related to ice core research: atmospheric chemistry/meteorology, climatological studies, geophysics, ice chemistry, particles, physical properties, stable isotopes and trace gas chemistry. This document includes summaries of the questionnaire results for each of these disciplines. (DCE)
- Climatic history from ice core studies in Greenland; data correction procedures; Current issues in climate research
W. Dansgaard, H. B. Clausen, D. Dahl-Jensen, N. Gundestrup and C. U. Hammer.
EC Climatology symposium, Sophia Antipolis
- Ice core record of the (super 13 C/ (super 12 C ratio of atmospheric CO (sub 2 in the past two centuries
H. Friedli, H. Loetscher, Hans Oeschger, U. Siegenthaler and B. Stauffer.
Nature (London), Vol. 324, No. 6094, 20 Nov 1986, pp. 237-238.
- Sulfate and nitrate concentrations from a South Greenland ice core
P. A. Mayewski, W. B. Lyons and M. J. Spencer, et al.
Science, Vol. 232, No. 4753, 23 May 1986, pp. 975-977.
- Greenland ice core studies
Palaeogeography, Palaeoclimatology, Palaeoecology, Vol. 50, No. 2-3, 1985, pp. 185-187.
- Increase of atmospheric methane recorded in Antarctic ice core
B. Stauffer, G. Fischer, A. Neftel and H. Oeschger.
Science, Vol. 229, No. 4720, 27 Sep 1985, pp. 1386-1388.
- Effect of wind scouring on climatic records from ice-core oxygen-isotope profiles
D. A. Fisher, R. M. Koerner, W. S. B. Paterson, W. Dansgaard, N. Gundestrup and N. Reeh.
Nature (London), Vol. 301, No. 5897, 20 Jan 1983, pp. 205-209.
- Ice core indications of abrupt climatic changes; Palaeoclimatic research and models; report and proceedings, workshop
W. Dansgaard, H. Oeschger and C. C. Langway.
Palaeoclimatic research and models; workshop, Brussels
- (super 36) Cl bomb pulse measured in a shallow ice core from Dye 3, Greenland
D. Elmore, L. E. Tubbs and D. Newman, et al.
Nature (London), Vol. 300, No. 5894, 23 Dec 1982, pp. 735-737.
- A new Greenland deep ice core
W. Dansgaard, H. B. Clausen and N. Gundestrup, et al.
Science, Vol. 218, No. 4579, 24 Dec 1982, pp. 1273-1277.
- Ice core studies: dating the past to find the future
Nature, London, Vol. 290, No. 5805, 1981, pp. 360-361.
All kinds of fallout from the atmosphere, such as airborne continental dust and biological material, volcanic debris, sea salts, cosmic particles, and cosmic-ray-produced isotopes, are deposited on the surface along with the snow each year and each year a new layer is added to the old in Antarctica and Greenland. The snowpack is gradually compressed into solid ice with small cavities containing samples of atmospheric air. In the coldest areas of the ice sheets, the impurities remain in the ice as deep-frozen indicators of the chemical composition and physical conditions of the atmosphere at the time of deposition. The composition of the ice layers changes only by the decay of the radioactive impurities and by extremely low diffusion processes in the ice crystal lattice. A number of dating methods have been developed on the basis of ice flow models and analysis of isotopes, volcanic debris, and continental dust in ice cores. The most accurate is the stratigraphic method. A new, more sensitive radioisotope ice dating technique will not be able to reveal the duration of the past climatic shift, but a counting of annual layers, deposited in a continuous sequence throughout the shift, may be feasible by modified detection techniques because such layers, each 1 mm thick, probably exist similar to 80 m above the bottom of the ice sheet in central Greenland.
- Tephra layers in the Byrd Station ice core and the Dome C ice core, Antarctica and their climatic importance; Volcanism and climate
P. R. Kyle, P. A. Jezek, E. Mosley-Thompson, L. G. Thompson, R. E. Newell and G. P. L. Walker.
Journal of Volcanology and Geothermal Research, Vol. 11, No. 1, 1981, pp. 29-39.
- Investigation of the nature of the microparticles from the Byrd Station, Antarctica, deep ice core and their relationship to the climate of that period
Ellen M. Thompson.
Master's Thesis, Ohio State University, Columbus, OH, United States (USA), 1975.
- Analysis of the concentration of microparticles in an ice core from Byrd Station, Antarctica
Lonnie G. Thompson.
Master's Thesis, Ohio State University, Columbus, OH, United States (USA), 1973.
- "Climatic record revealed by the Camp Century ice core"
The late Cenozoic glacial ages
W. Dansgaard, S. J. Johnsen, H. B. Clausen and C. C. Langway Jr.
International (III): Yale Univ. Press, New Haven-London,