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Joseph Galewsky and David Rabanus

and confirmed that the mixing ratio bias had been corrected. The Picarro mixing ratios were within about 2% of those measured at the array operations site, a difference that we determined to be insignificant for the analysis presented below. The replacement isotopic analyzer was subjected to the same concentration dependence correction and standardization as our original system, so we believe that the data obtained by the two instruments are comparable. We used the ERA-Interim dataset ( Dee et al

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Hiroshi Matsuyama, Kunihide Miyaoka, and Kooiti Masuda

.60°S, 56.10°W, 165 m ASL), one of the IAEA/GNIP stations, is located on the northern fringe of Pantanal, which is the largest wetland in the world ( Fig. 1 ). Here, Dansgaard (1964) found that the amount effect of precipitation was important for the isotopic variations, by the preliminary analysis of the IAEA/GNIP database from 1961 to 1962. Dansgaard (1964) also mentioned that the temperature effect was insignificant for the isotopic variations at Cuiabá, since it is located in the Tropics

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Charles A. Knight, Dieter H. Ehhalt, Nathaniel Roper, and Nancy C. Knight

issomewhat questionable, however, and the data are notextensive enough to allow a check on the basis ofconsistency.g. Other isotopes While O~s measurements are not expected to addnew information, they are a worthwhile check on theD-values. Additional information might be derivablefrom tritium analysis. The tritium content of a stonef*rom Chadron, Neb., is shown in Fig. 12i, with itsD-profile. The radioactive isotope, T, was producedby thermonuclear bombs and introduced in largeamounts into the

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J. A. Warburton and L. G. Young

analysis. However, in view of the likelihood of a considerably highernatural background of iodine than of silver, it seemedwiser to choose silver as the better analysis element.3. Choices of method for neutron activation analysis of silver The natural isotopes of silver and their abundancesare Ag~-7 (51.35%) and Ag~-9 (48.65%), neither of whichis radioactive. When placed in a nuclear reactor and subjected tofluxes of neutrons both of thermal energy (~0.025eV) and higher (up to 10 MeV), many

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Ronald B. Smith

vapor and liquid they wereable to distinguish regions dominated by upwellingcloud droplets from regions dominated by falling raindrops. In this study we have collected and analyzed D/Hin ice from the tops of winter cyclones over the NorthAtlantic Ocean. This particular approach to cloud-isotope studies was chosen to simplify the interpretationof the data as much as possible. There are several complicating factors that we have tried to avoid. For example, the analysis of D/H instead of O ~8/O 16

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Andrew Rhines and Peter J. Huybers

central Greenland ice cores, though variations in wind speed, water vapor saturation, and other environmental parameters could remain important variables. Further analysis comparing simulations of isotopic composition (e.g., Lewis et al. 2013 ) against observations, including triple oxygen isotope analysis (e.g., Uemura et al. 2008 ; Steen-Larsen et al. 2014 ), would be useful for better ascertaining the role of the sea ice edge in controlling the composition of Greenland’s accumulation

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David H. Bromwich, Aric N. Rogers, Per Kållberg, Richard I. Cullather, James W. C. White, and Karl J. Kreutz

based upward trend lends more support to the larger positive trend obtained from TOGA analyses or to the smaller one from ERA-15. 2) Isotope analysis of a Siple Dome ice core Deuterium isotope concentrations from ice-core analyses serve as a proxy for variations of moisture flux convergence into the West Antarctic sector and should be correlated with ENSO events. The reason for this is due primarily to the positioning of the low pressure center in the Amundsen Sea and to a relationship between

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David C. Chapman and Robert C. Beardsley

MARCH 1989 NOTES AND CORRESPONDENCE 384 NOTES AND CORRESPONDENCE On the Origin of Shelf Water in the Middle Atlantic Bight* DAVID C. CHAPMAN ANO ROBERT C. BEARDSLEY Woods Hole Oceanographic Institution, Woods Hole. Massachusetts 6 June 1988 and 15 August 1988 ABSTRACT Based on a limited set of available oxygen isotope measurements, it is

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D. A. Gillette, R. N. Clayton, T. K. Mayeda, M. L. Jackson, and K. Sridhar

to 80 ~ra range aswell as in the 1 to 30/am range. The concentration of dust 2 to 5 km above the ground, measured byboth the filtering and impactor methods, ranged from 0.1 to 0.4 mg m-~ for four intense dust storms inTexas during April of 1972 and 1973. The vertical flux for dust storms over the four-year period rangedfrom 0.25X10-? to 2.2x10-a g c..m-s s-z. Oxygen isotopic ratio values of 1 to 10/am quartz isolated from 17 dusts collected by ground-basedsamplers ranged from 16.4 to 19.5Y

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Jing Gao, You He, Valerie Masson-Delmotte, and Tandong Yao

. 2004 , 2001 ; Sankar et al. 2011 ). The ENSO signal could be probed at the interannual scale using ice core records in the Tibetan Plateau (TP), but there is only a weak statistical relationship between ice core δ 18 O and the ENSO index ( Thompson et al. 2000a ; Yang et al. 2000 ). Here, we try to clarify the impact of ENSO on the precipitation isotopic composition ( δ 18 O p ) in the southern TP and the underlying mechanisms. Recent studies have been focused on mechanisms of intra

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