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Rhein, M, Fischer J, Smethie WM, Smythe-Wright D, Weiss RF, Mertens C, Min DH, Fleischmann U, Putzka A.  2002.  Labrador Sea Water: pathways, CFC inventory, and formation rates. Journal of Physical Oceanography. 32:648-665.   10.1175/1520-0485(2002)032<0648:lswpci>;2   AbstractWebsite

In 1997, a unique hydrographic and chlorofluorocarbon (CFC: component CFC-11) dataset was obtained in the subpolar North Atlantic. To estimate the synopticity of the 1997 data, the recent temporal evolution of the CFC and Labrador Sea Water (LSW) thickness fields are examined. In the western Atlantic north of 50degreesN, the LSW thickness decreased considerably from 1994-97, while the mean CFC concentrations did not change much. South of 50degreesN and in the eastern Atlantic, the CFC concentration increased with little or no change in the LSW thickness. On shorter timescales, local anomalies due to the presence of eddies are observed, but for space scales larger than the eddies the dataset can be treated as being synoptic over the 1997 observation period. The spreading of LSW in the subpolar North Atlantic is described in detail using gridded CFC and LSW thickness fields combined with Profiling Autonomous Lagrangian Circulation Explorer (PALACE) float trajectories. The gridded fields are also used to calculate the CFC-11 inventory in the LSW from 40degrees to 65degreesN, and from 10degrees to 60degreesW. In total, 2300 +/- 250 tons of CFC-11 (equivalent to 16.6 million moles) were brought into the LSW by deep convection. In 1997, 28% of the inventory was still found in the Labrador Sea west of 45degreesW and 31% of the inventory was located in the eastern Atlantic. The CFC inventory in the LSW was used to estimate the lower limits of LSW formation rates. At a constant formation rate, a value of 4.4-5.6 Sv (Sv = 10(6) m(3) s(-1)) is obtained. If the denser modes of LSW are ventilated only in periods with intense convection, the minimum formation rate of LSW in 1988-94 is 8.1-10.8 Sv, and 1.8-2.4 Sv in 1995-97.

Imboden, DM, Weiss RF, Craig H, Michel RL, Goldman CR.  1977.  Lake Tahoe geochemical study .1. Lake chemistry and tritium mixing study. Limnology and Oceanography. 22:1039-1051. AbstractWebsite
Krishnaswami, S, Lal D, Somayajulu BLK, Weiss RF, Craig H.  1976.  Large-volume in situ filtration of deep Pacific waters: mineralogical and radioisotope studies. Earth and Planetary Science Letters. 32:420-429.   10.1016/0012-821x(76)90082-0   AbstractWebsite

The concentrations of CaCO3 and radioisotopes,234Th,230Th,239Pu,226Ra and210Pb have been measured in particles of >1.2 μm collected from ∼4000 liters of Pacific waters (33°N−33°S; 124°W−170°E) at depths 700–5500 m. The mean “ash” concentrations are found to be 5 μg/kg seawater, about 3–4 times lower than that in the surface waters. The particulate concentrations (dpm/kg seawater) of239Pu shows a peak at 700–1000 m, whereas the particulate concentration of230Th and210Pb which are produced in-situ in seawater increases with depth. These results provide an insight into certain aspects of particle dynamics relevant to modification of trace element composition of seawater due to particle transport and sedimentation flux. The salient features of the results are:(1) The mean settling velocity of particles are in the range of (0.3−2) × 10−3 cm/sec corresponding to a sedimentation rate of 0.1−0.6 cm/103 yr.(2) The rate constant for the adsorption of Th on particles is deduced to be 8 × 10−8 sec−1 assuming a first-order scavenging model.

Fraser, P, Cunnold D, Alyea F, Weiss R, Prinn R, Simmonds P, Miller B, Langenfelds R.  1996.  Lifetime and emission estimates of 1,1,2-trichlorotrifluorethane (CFC-113) from daily global background observations June 1982 June 1994. Journal of Geophysical Research-Atmospheres. 101:12585-12599.   10.1029/96jd00574   AbstractWebsite

Observations every two hours of CCl2FCClF2 at Mace Head, Ireland (February 1987-June 1994); Cape Meares, Oregon (April 1984-June 1989); Ragged Point, Barbados (October 1985-June 1994); Cape Matatula, Samoa (October 1985-June 1989 and January 1992-June 1994); and Cape Grim, Tasmania (June 1982-June 1994) are reported, The observations from Cape Grim have been extended back to 1978 using archived air samples. The global atmospheric abundance of CCl2FCClF2 is indicated to have been growing exponentially between 1978 and 1987 with an e-folding time of approximately 7.6 years; it has been growing less rapidly since that time. On January 1, 1994, the mean inferred northern hemispheric mixing ratio in the lower troposphere was 84.4 +/- 0.4 ppt and the southern hemispheric value was 80.6 +/- 0.4 ppt; the global growth rate in 1991-1993 is estimated to have averaged approximately 3.1 +/- 0.1 ppt/year. The differences between the northern and southern hemispheric concentrations are calculated to be consistent with the almost entirely northern hemispheric release of this gas. The annual release estimates of CCl2FCClF2 by industry, which include estimates of eastern European emissions, fairly consistently exceed those deduced from the measurements by approximately 10% from 1980 to 1993. The uncertainties in each estimate is approximately 5%. This difference suggests that up to 10% of past production might not yet have been released. The measurements indicate that atmospheric releases of CCl2FCClF2 have been decreasing rapidly since 1989 and in 1993 amounted to 78 +/- 27 x 10(6) kg or 42 +/- 15% of the 1985-1987 emissions.

Clerbaux, C, Cunnold DM, Anderson J, Engel AEJ, Fraser PJ, Mahieu E, Manning A, Miller J, Montzka SA, Nassar R, Prinn R, Reimann S, Rinsland CP, Simmonds P, Verdonik D, Weiss R, Wuebbles D, Yokouchi K.  2007.  Long-lived compounds. Scientific assessment of ozone depletion, 2006 (World Meteorological Organization, Global Ozone Research and Monitoring Project, Report 50). :83., Geneva, Switzerland: World Meteorological Organization Abstract
Prinn, RG, Zander R, Cunnold DM, Elkins JW, Engel A, Fraser PJ, Gunson MR, Ko MKW, Mahieu E, Midgley PM, Russel III JM, Volk CM, Weiss RF.  1999.  Long-lived ozone-related compounds. Scientific assessment of ozone depletion, 1998 (World Meteorological Organization, Global Ozone Research and Monitoring Project Report 44). :54., Washington, DC: National Oceanic and Atmospheric Administration Abstract
Reimann, S, Manning AJ, Simmonds PG, Cunnold DM, Wang RHJ, Li JL, McCulloch A, Prinn RG, Huang J, Weiss RF, Fraser PJ, O'Doherty S, Greally BR, Stemmler K, Hill M, Folini D.  2005.  Low European methyl chloroform emissions inferred from long-term atmospheric measurements. Nature. 433:506-508.   10.1038/nature03220   AbstractWebsite

Methyl chloroform (CH3CCl3, 1,1,1,-trichloroethane) was used widely as a solvent before it was recognized to be an ozone-depleting substance and its phase-out was introduced under the Montreal Protocol(1). Subsequently, its atmospheric concentration has declined steadily(2-4) and recent European methyl chloroform consumption and emissions were estimated to be less than 0.1 gigagrams per year(1,5). However, data from a short-term tropospheric measurement campaign ( EXPORT) indicated that European methyl chloroform emissions could have been over 20 gigagrams in 2000 (ref. 6), almost doubling previously estimated global emissions(1,4). Such enhanced emissions would significantly affect results from the CH3CCl3 method of deriving global abundances of hydroxyl radicals ( OH) (refs 7 - 12) - the dominant reactive atmospheric chemical for removing trace gases related to air pollution, ozone depletion and the greenhouse effect. Here we use long-term, high-frequency data from MaceHead, Ireland and Jungfraujoch, Switzerland, to infer European methyl chloroform emissions. We find that European emission estimates declined from about 60 gigagrams per year in the mid-1990s to 0.3 - 1.4 and 1.9 - 3.4 gigagrams per year in 2000 - 03, based on Mace Head and Jungfraujoch data, respectively. Our European methyl chloroform emission estimates are therefore higher than calculated from consumption data(1,5), but are considerably lower than those derived from the EXPORT campaign in 2000 ( ref. 6).