Ice core samples

Neftel, A., Oeschger, H., Schwander, J., Stauffer, B. and Zumbrunn, R. (1982). Ice core sample measurements give atmospheric CO2 content during the past 40,000 yr. Nature 295,220-223. 

Surface samples were collected in snow pits under ultra-clean conditions described elsewhere [13] with the exception that samples for anion analysis were collected in polystyrene cups precleaned without the use of acids. Ice core samples were cleaned to remove surface contamination using the "dry-core" procedure involving rinsing and melting of exterior surfaces with ultra-pure water [13]. Shallow-depth firn cores are permeable and the dry-core rinsing is unsuitable. Therefore an inner core of 2.5 cm diameter was taken from intervals of the 7.6 cm diameter South Pole firn core using a specially-built precleaned stainless steel corer within a -15 °C cold room. Prior to this coring, exposed ends of core sections were shaved away with precleaned stainless steel chisels. 

Figure 6. Concentrations of SOt2 and Cl" (in ng/g) in Milcent, Greenland ice core samples deposited following the 1783 eruption of Laki in Iceland. The acid precipitation that followed this eruption left an unmistakable glaciochemical horizon...

Uchida, T. Hondoh, T. Mae, S. Lipenkov, V.Y. Duval, P. (1994). Air-hydrate crystals in deep ice-core samples from Vostok Station Antartica. J. Glaciology, 40 (134), 79-88. 

Like C02 and CH4, the concentrations of N20 in the atmosphere have also been increasing, from 275 ppb in the preindustrial era to 312 ppb in 1994 (IPCC, 1996). Figure 14.19, for example, shows one set of measurements of N20 over the past 250 years obtained using ice core samples from Antarctica... 

Ice core samples from Vostok, Antarctic, look back over 400,000 years before present at atmospheric CO2 levels by examining the composition of air bubbles trapped in the polar ice buried over 3623 m (11,886 ft) deep.5 These data show that the range of CO2 concentrations over this time period have been relatively stable, cycling between about 180 and 300 parts per million by volume (ppmv). According to the World Meteorological Organization the CO2 concentration in 2005 reached an unprecedented 379.1 ppmv.6... 

Neftel a., Oeschger H., Schwander J., Stauffer B. and Zumbrunn R., New measurements on ice core samples to determine the CO2 content of the atmosphere during the last 40,000 years. Nature , 295, 220-223 (1982). 

Removal of the outer contaminated parts of an ice core or snow sample is fundamental to the reliable analysis of metals. This has been amply demonstrated on ice cores by Ng and Patterson (10) who showed that outer layers were very contaminated, but could be effectively removed by mechanical means. This was later demonstrated by measurements on Dome C and Vostok ice core samples by Patterson and Boutron (12) and Boutron et al. (35). A similar approach was successfully used to decontaminate blocks of Antarctic snow (28, 36). Candelone et al. (11) refined the decontamination of ice cores by constructing a polyethylene lathe. The procedural blank for the decontamination process with the lathe was determined on an artificial core, and found to be 0.11 pg/g. 

Polar deep ice. Polar deep ice is made of snow under a compressing process. The dielectric properties of polar ice core samples have been reported as having small values of relaxation time rand activation energy.The observation of small rvalues for the core ice samples suggests that Bjerrum defects are more numerous in polar ice than in ordinary ice. The impurity concentration of polar ice is not sufficiently high to decrease the rvalue the HCl concentration is about 2x10 mol/1 for Byrd core ice. Since we know that polar deep ice has structures of clathrate gas hydrate, imperfection in the structures and the existence of gas molecules in the ice lattice seem to affect the dielectric properties.It is well known that the dielectric properties of ice samples derived from polar deep ice that has melted and refrozen are similar to those of ordinary ice. ... 

Glacial ice core samples indicate pre-industrial-age levels of atmospheric chlorine at <1 ppb. By the late 20th century, the concentration had reached 3.6 ppb. Continuation of current efforts may return the Earth s atmosphere to <1 ppb levels shortly after year 2100. The following link provides a summary analysis of CEC/HCEC atmospheric conditions compiled by the Canada Chemical Producers Association http //en.wikipedia.org/wiki/ozone layer. 

Neftel, A., H. Oeschger, J. Schwander, B. Stauffer, and R. Zumbrunn (1983). Ice core sample measurements give atmospheric C02 content during the last 40,000 years. Nature 295, 220-223. 

Figure 5. Sulfur isotope compositions of sulfuric acid aerosols in South Pole ice core samples. Aerosols from two eruptions, Pinatubo and AD 1259 that injected SO2 into the stratosphere have anomalously fractionated S- S- S (39).

Measuring the DMS oxidation products DMSO and DMSO2 in rain water provides information about atmospheric concentrations of DMS, and their measurement in ice-core samples from polar regions can be helpful for assessing paleo-climatic conditions. 

Climate sensitivity, AT/AF, is the mean change in global temperature that occurs in response to a specified forcing. From ice core samples (T, CO2, etc.), it is found between glacial and interglacial periods that... 

Air bubbles were extraeted using the cheese grater technique. Ice core samples weighing 500-1500 g were prepared by selecting crack-free iee and trimming away the outer 5-20 mm. Eaeh sample was sealed in a polyethylene bag and cooled to... 

Ice core samples from the Greenland Ice Sheet. The samples, stored at -33°F, are examined for evidence of global warming. 

As you have seen, NO2, SO2, and SO3 can both react with water in the atmosphere to produce acids NO2 produces nitric acid (HNO3) and nitrous acid (HNO2) SO3 and SO2 produce sulfuric acid (H2SO ) and sulfurous acid (H2SO3). When conditions are favorable, water droplets carrying these acids precipitate as rain or snow with a low pH. Ice core samples taken in Greenland and dating back to 1900 contain sulfate (SO ) and nitrate (NO ) ions. This indicates that at least from 1900 onward, acid rain has been commonplace. 

Perkins S (2006) Cold and deep Antarctica s Lake Vostok has two big neighbors. Science News 169 (Februtuy 4) 69-70 Peikins, S (2008) Down with caibon. Science News, May 10 18-23 Peterson JA, Moresby IF (1979) Subgladal travertine tmd associated deposits in the Qrtstensz area, Irian Jaya, Republic of Indonesia Zeitschrift fur Gletscherkunde und Glazialgeologie 15 23-29 Petit JR, Briat M, Royer A (1981) Ice age aerosol content from East Antarctic ice core samples tmd past wind strength. Nature 293 391-394... 

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