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Paul A. Dodd, Martin R. Price, Karen J. Heywood, and Miles Pebody

rotary valve were then flushed with water from the carboy. Finally, a second set of salinity and tracer samples was taken from the carboy to monitor any change in prime water properties during the procedure. After the recovery of Autosub, sample bags were detached from the AquaLAB and each sample was divided between one 150-mL bottle for salinity measurement, two 50-mL bottles for oxygen isotope analysis, and one 5-mL bottle for barium analysis. Because three sets of samples were required from this

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J. Rosinski

spatial distribution of solid particles in hailstones shouldbe supplemented by isotopic analysis.1. Introduction List (1965) has pointed out many times that "a hailstone can be regarded as a sonde, fallen through athunderstorm cloud, its life history imprinted in itsstructure." Attempts have been made to decipher themechanism of hailstone formation by studying entrapped water-insoluble particles (Rosinski, 1966). Byapplying similar studies to rain it should be possible tolearn more about the

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Xiaojuan Liu and David S. Battisti

surface air temperature. 4. Analysis of isotopic responses The decomposition method shown in Eqs. (2) and (3) is used to quantitatively illuminate the reason for changes in δ 18 O p . Using the monthly δ 18 O from high insolation and the monthly precipitation of low insolation in the calculation of [Eq. (2) ], we isolate the differences in δ 18 O p caused by changes in the seasonality of precipitation; the result is displayed in Fig. 6c . Similarly, using the monthly precipitation from

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Ronald B. Smith, Idar Barstad, and Laurent Bonneau

definition of the drying ratio (2) or (9) To apply this formula to orographic precipitation, we require the isotope ratio in precipitation in the extreme upwind and downwind locations. Ideally, samples for this analysis could be obtained from collectors during the rainfall event. An easier method, yielding more representative samples, is the collection of stream water. Stream water will retain the isotope ratio of rainfall if evaporation of soil water is minimal or if evaporation is nonfractionating

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Peter D. Ditlevsen, Mikkel S. Kristensen, and Katrine K. Andersen

threshold. This has the consequence that a warm period can more easily be split into more periods, as perhaps happens for DO event 17 ( Schulz 2002a ). The definitions applied here clearly identify whether DO event 17 should be regarded as one or two events. In our analysis, it remains one DO event (GI17). In the following, the lower threshold is chosen as −1.0 permil anomaly and the higher threshold as +1.5 permil anomaly from the 10-kyr. high-pass isotope signal. The asymmetry is because the climate

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T. R. Krishna Mohan, J. Subba Rao, and R. Ramaswamy

due to strange attractors (SAs) in theconfiguration space dynamics. One climatic record, the oxygen isotope ratio data from deep-sea cores thatpertains to long periods on the order of one million years and provides direct correlation with the glaciationdeglaciation periods, seemed to indicate (under earlier analysis) a low dimensional attractor of correlationdimension D2 ~ 3.1. Our present reanalysis of this data in light of recent methods suggested by Broomheadand King (BK) is at variance with

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M. López-Puertas, M. A. López-Valverde, and F. W. Taylor

form 23 August 1989)ABSTRACT Solar heating and thermal cooling rates by the CO2 near-infrared bands~ in the mesosphere and lower thermosphere are derived from measurements of the CO2 4.3 ~m atmospheric emission by the Stratospheric andMesospheric Sounder on Nimbus 7. A detailed analysis of the relaxation of the solar energy initially absorbedby the different bands, before it escapes to space or is thermalized, is included. The isotopic and hot bands ofCO2 near 4.3 ~m play an important role since

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C. A. M. Brenninkmeijer, P. J. Crutzen, H. Fischer, H. Güsten, W. Hans, G. Heinrich, J. Heintzenberg, M. Hermann, T. Immelmann, D. Kersting, M. Maiss, M. Nolle, A. Pitscheider, H. Pohlkamp, D. Scharffe, K. Specht, and A. Wiedensohler

sensor as well as a conventional ozone monitor, a gas chromatograph for CO analysis, two condensation nuclei counters for submicron particles larger than 5 and 12 nm, and the 12 canister large-capacity whole air sampler for postflight concentration and isotopic measurement in the laboratory. With the exception of the fast-response ozone sensor and the whole air sampler, all apparatus are commercially available laboratory instruments that have undergone varying degrees of modifications and

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Nicklas G. Pisias, Peter U. Clark, and Edward J. Brook

1. Introduction Millennial-scale climate variability is a persistent feature in the spectrum of climate change ( Mitchell 1976 ). Among the best-known expressions of this variability are the Dansgaard–Oeschger (D-O) Oscillations recorded in Greenland ice cores during Marine Isotope Stage 3 (MIS 3) 60–25 ka ( Grootes et al. 1993 ). MIS 3 millennial-scale variability is also recorded in Antarctic ice cores, but with a fundamentally different structure (so-called A events) than seen in Greenland

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C. A. M. Brenninkmeijep and P. A. Roberts

special attention to the problem ofcollecting air in the lower stratosphere for the isotopic analysis of carbon monoxide.1. Introduction Isotopic analysis is being increasingly used for betterunderstanding the cycles of atmospheric trace gases,and in several cases rather unique information is beingobtained. For instance the ~4C activity of atmosphericCH4, when combined with its ~3C/~2C ratio is a goodestimator of the biogenic fraction of this greenhousegas (Lowe et al. 1988; Wahlen et al. 1989). In

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