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David J. Gochis, Juan-Carlos Leal, W. James Shuttleworth, Christopher J. Watts, and Jaime Garatuza-Payan

enhancements will increase sampling in this interval. d. Coordinated isotopic sampling In addition to the automatic, tipping-bucket rain gauge network, 12 bulk rainfall collectors were deployed at selected sites for the collection and analysis of isotopes. Isotopes can potentially serve as atmospheric and terrestrial tracers of moisture sources, paths, and processes. These sites, shown as white squares on Fig. 1 , are intended to sample the longitudinal and elevational gradient of isotope content in

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S. Kaspari, P. A. Mayewski, M. Handley, S. Kang, S. Hou, S. Sneed, K. Maasch, and D. Qin

the largest dust sources on earth. Thus, ice cores from these regions provide invaluable natural archives of past dust variability and composition. Himalayan glaciers have previously been identified as among the best locations for retrieving ice cores that provide detailed records of the long-range transport of Asian dust ( Wake et al. 1993 , 1994 ). Asian ice cores to date have predominantly been analyzed for major ions and stable isotopes ( Kang et al. 2002 ; Thompson et al. 2000 ). However

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Maud Comboul, Julien Emile-Geay, Gregory J. Hakim, and Michael N. Evans

, doi: 10.1061/(ASCE)WR.1943-5452.0000081 . Juillet-Leclerc , A. , and G. A. Schmidt , 2001 : A calibration of the oxygen isotope paleothermometer of coral aragonite from porites . Geophys. Res. Lett. , 28 , 4135 – 4138 , doi: 10.1029/2000GL012538 . Kaplan , A. , Y. Kushnir , M. A. Cane , and M. B. Blumenthal , 1997 : Reduced space optimal analysis for historical data sets: 136 years of Atlantic sea surface temperatures . J. Geophys. Res. , 102 ( C13 ), 27 835 – 27 860 , doi

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Robert E. Dickinson

the upper atmosphere of Venus. Weespecially consider the region between 90 and 130 kin, where the equilibrium temperature is largely controlled through infrared absorption and emission by vibrational-rotational bands of COx. Source functionsfor bands deviating from thermodynamic equilibrium are determined as part of the calculation. Radiativetransfer in the region of non-overlapping lines is calculated by summing the contribution of individualVoigt lines. Many isotopic and hot bands contribute

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Lauren Elmegreen Rafelski, Bill Paplawsky, and Ralph F. Keeling

shipboard analysis of dissolved oceanic trace gases . Anal. Chim. Acta , 395 , 119 – 132 . Juranek, L. W. , and Quay P. D. , 2005 : In vitro and in situ gross primary and net community production in the North Pacific Subtropical Gyre using labeled and natural abundance isotopes of dissolved O 2 . Global Biogeochem. Cycles , 19 , GB3009 , doi:10.1029/2004GB002384 . Kaiser, J. , Reuer M. K. , Barnett B. , and Bender M. L. , 2005 : Marine productivity estimates from continuous O 2 /Ar

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Michael E. Mann, Mark A. Cane, Stephen E. Zebiak, and Amy Clement

feedbacks) that respond differently in different models and are admittedly absent in the ZC model. Here we investigate the response of ENSO to estimated changes in natural radiative forcing associated with explosive volcanic and solar radiative forcing changes over the past 1000 yr. Several new and distinct insights from the paleoclimate record of the past few centuries guide these investigations: (i) An analysis of reconstructed sea surface temperature (SST) patterns over the past few centuries

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Vincent Bustillo, Reynaldo Luiz Victoria, Jose Mauro Sousa de Moura, Daniel de Castro Victoria, Andre Marcondes Andrade Toledo, and Erich Colicchio

to inputs and outputs. By comparing the outputs of many different models designed for different purposes, the nature and the magnitude of processes linking water and biogeochemical budgets of the Amazonian floodplains were clarified. Each one provides a specific insight on the soil–river system dynamics by coupling hydrological, sedimentary, and biogeochemical budgets. The comparison of the model outputs, and the analysis of their reciprocal consistency, enabled us to decipher much more assuredly

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Yu-Long Xie, Philip K. Hopke, Pentti Paatero, Leonard A. Barrie, and Shao-Meng Li

showed that about 62%–74% of sulfates in the summer and 78%–85% of sulfates in the winter are of anthropogenic origin ( Li and Barrie 1993 ; Li et al. 1993 ). Results of an analysis of the isotopic composition of sulfur in the Arctic haze suggested that most of the sulfur comes from Europe rather than more local areas ( Nriagu et al. 1991 ). With the aid of meteorological information, Cheng et al. (1993) and Hopke et al. (1995) investigated the source origin and preferred pathways for sulfur

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Axel Timmermann, Oliver Timm, Lowell Stott, and Laurie Menviel

this region, higher-resolution modeling studies ( Noone and Simmonds 2004 ) are needed. In the analysis presented above, the spatial averaging over a relatively large area (90°S–60°S) averages out some sea ice advection and lateral advection effects. Oxygen and hydrogen isotope ratios measured in ice cores in Antarctica represent a proxy for the precipitation-weighted condensation temperature. Understanding isotope variations in terms of a precipitation-weighted temperature requires an accurate

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Peter E. Wilkniss, John W. Swinnerton, David J. Bressan, Robert A. Lamontagne, and Reginald E. Larson

Range.A large air sample was collected between 40 and 50 km altitude and successfully recovered for water vaporand trace gas analysis. The results were as follows: water vapor, 4.0-+o~i~ ppmV; methane, 0.374-0.01 ppmV;molecular hydrogen, 0.474-0.02 ppmV; carbon monoxide, 0.054-0.01 ppmV; carbon dioxide, 316.24-2.8ppmV; and nitrous oxide, 34-7 ppb.1. Introduction On 23 May 1973 a cryogenic air sampler wasflown successfully on an Aerobee-150 rocket fromWhite Sands Missile Range, New Mexico (31N

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