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Carmack, EC, Weiss RF.  1991.  Convection in Lake Baikal: an example of thermobaric instability. Deep Convection and Deep Water Formation in the Oceans. ( Chu PC, Gascard JC, Eds.).:215-228., Burlington: Elsevier Abstract

This book contains articles presenting current knowledge about the formation and renewal of deep waters in the ocean. These articles were presented at an international workshop at the Naval Postgraduate School in Monterey in March 1990.

Chan, LH, Edmond JM, Stallard RF, Broecker WS, Chung YC, Weiss RF, Ku TL.  1976.  Radium and barium at Geosecs stations in Atlantic and Pacific. Earth and Planetary Science Letters. 32:258-267.   10.1016/0012-821x(76)90066-2   AbstractWebsite

Ra and Ba show a general linear correlation in the oceanic water column within the uncertainties of the data: the slope of the line is about 4.6 nanomoles (nmoles) Ra/mole Ba, the intercept being at about 4 nmoles Ba/kg. This demonstrates the usefulness of Ba as a “chemical analogue” of Ra. Box-model calculations indicate that the average deep-water excess of Ra over Ba should be about 10% relative to the surface. This is consistent with the observations outside the deep northeast Pacific. However, the uncertainties in the data are such that the regional variation in the primary input cannot be resolved. In the deep waters of the North Pacific there is in fact a large excess of Ra relative to Ba. The one detailed profile presently available (204) can be explained consistently by a simple vertical advection-diffusion model.

Chipperfield, MP, Liang Q, Rigby M, Hossaini R, Montzka SA, Dhomse S, Feng WH, Prinn RG, Weiss RF, Harth CM, Salameh PK, Muhle J, O'Doherty S, Young D, Simmonds PG, Krummel PB, Fraser PJ, Steele LP, Happell JD, Rhew RC, Butler J, Yvon-Lewis SA, Hall B, Nance D, Moore F, Miller BR, Elkins J, Harrison JJ, Boone CD, Atlas EL, Mahieu E.  2016.  Model sensitivity studies of the decrease in atmospheric carbon tetrachloride. Atmospheric Chemistry and Physics. 16:15741-15754.   10.5194/acp-16-15741-2016   AbstractWebsite

Carbon tetrachloride (CCl4) is an ozone-depleting substance, which is controlled by the Montreal Protocol and for which the atmospheric abundance is decreasing. However, the current observed rate of this decrease is known to be slower than expected based on reported CCl4 emissions and its estimated overall atmospheric lifetime. Here we use a three-dimensional (3-D) chemical transport model to investigate the impact on its predicted decay of uncertainties in the rates at which CCl4 is removed from the atmosphere by photolysis, by ocean uptake and by degradation in soils. The largest sink is atmospheric photolysis (74% of total), but a reported 10% uncertainty in its combined photolysis cross section and quantum yield has only a modest impact on the modelled rate of CCl4 decay. This is partly due to the limiting effect of the rate of transport of CCl4 from the main tropospheric reservoir to the stratosphere, where photolytic loss occurs. The model suggests large interannual variability in the magnitude of this stratospheric photolysis sink caused by variations in transport. The impact of uncertainty in the minor soil sink (9% of total) is also relatively small. In contrast, the model shows that uncertainty in ocean loss (17% of total) has the largest impact on modelled CCl4 decay due to its sizeable contribution to CCl4 loss and large lifetime uncertainty range (147 to 241 years). With an assumed CCl4 emission rate of 39 Gg year(-1), the reference simulation with the best estimate of loss processes still underestimates the observed CCl4 (overestimates the decay) over the past 2 decades but to a smaller extent than previous studies. Changes to the rate of CCl4 loss processes, in line with known uncertainties, could bring the model into agreement with in situ surface and remote-sensing measurements, as could an increase in emissions to around 47 Gg year(-1). Further progress in constraining the CCl4 budget is partly limited by systematic biases between observational datasets. For example, surface observations from the National Oceanic and Atmospheric Administration (NOAA) network are larger than from the Advanced Global Atmospheric Gases Experiment (AGAGE) network but have shown a steeper decreasing trend over the past 2 decades. These differences imply a difference in emissions which is significant relative to uncertainties in the magnitudes of the CCl4 sinks.

Chirkov, M, Stiller GP, Laeng A, Kellmann S, von Clarmann T, Boone CD, Elkins JW, Engel A, Glatthor N, Grabowski U, Harth CM, Kiefer M, Kolonjari F, Krummel PB, Linden A, Lunder CR, Miller BR, Montzka SA, Mühle J, O'Doherty S, Orphal J, Prinn RG, Toon G, Vollmer MK, Walker KA, Weiss RF, Wiegele A, Young D.  2016.  Global HCFC-22 measurements with MIPAS: retrieval, validation, global distribution and its evolution over 2005–2012. Atmos. Chem. Phys.. 16:3345-3368.: Copernicus Publications   10.5194/acp-16-3345-2016   AbstractWebsite

We report on HCFC-22 data acquired by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) in the reduced spectral resolution nominal observation mode. The data cover the period from January 2005 to April 2012 and the altitude range from the upper troposphere (above cloud top altitude) to about 50 km. The profile retrieval was performed by constrained nonlinear least squares fitting of modelled spectra to the measured limb spectral radiances. The spectral ν4-band at 816.5 ± 13 cm−1 was used for the retrieval. A Tikhonov-type smoothing constraint was applied to stabilise the retrieval. In the lower stratosphere, we find a global volume mixing ratio of HCFC-22 of about 185 pptv in January 2005. The rate of linear growth in the lower latitudes lower stratosphere was about 6 to 7 pptv year−1 in the period 2005–2012. The profiles obtained were compared with ACE-FTS satellite data v3.5, as well as with MkIV balloon profiles and cryosampler balloon measurements. Between 13 and 22 km, average agreement within −3 to +5 pptv (MIPAS – ACE) with ACE-FTS v3.5 profiles is demonstrated. Agreement with MkIV solar occultation balloon-borne measurements is within 10–20 pptv below 30 km and worse above, while in situ cryosampler balloon measurements are systematically lower over their full altitude range by 15–50 pptv below 24 km and less than 10 pptv above 28 km. MIPAS HCFC-22 time series below 10 km altitude are shown to agree mostly well to corresponding time series of near-surface abundances from the NOAA/ESRL and AGAGE networks, although a more pronounced seasonal cycle is obvious in the satellite data. This is attributed to tropopause altitude fluctuations and subsidence of polar winter stratospheric air into the troposphere. A parametric model consisting of constant, linear, quasi-biennial oscillation (QBO) and several sine and cosine terms with different periods has been fitted to the temporal variation of stratospheric HCFC-22 for all 10°-latitude/1-to-2-km-altitude bins. The relative linear variation was always positive, with relative increases of 40–70 % decade−1 in the tropics and global lower stratosphere, and up to 120 % decade−1 in the upper stratosphere of the northern polar region and the southern extratropical hemisphere. Asian HCFC-22 emissions have become the major source of global upper tropospheric HCFC-22. In the upper troposphere, monsoon air, rich in HCFC-22, is instantaneously mixed into the tropics. In the middle stratosphere, between 20 and 30 km, the observed trend is inconsistent with the trend at the surface (corrected for the age of stratospheric air), hinting at circulation changes. There exists a stronger positive trend in HCFC-22 in the Southern Hemisphere and a more muted positive trend in the Northern Hemisphere, implying a potential change in the stratospheric circulation over the observation period.

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
Craig, H, Weiss RF, Clarke WB.  1967.  Dissolved gases in Equatorial and South Pacific Ocean. Journal of Geophysical Research. 72:6165-&.   10.1029/JZ072i024p06165   AbstractWebsite

The nitrogen, oxygen, and argon in Pacific samples from two expeditions have been measured by gas chromatography, and the neon and helium by mass spectrometry. Nitrogen is systematically about 2% supersaturated and argon about 1.5% undersaturated, relative to the solubility data of Douglas for a moisture saturated atmosphere at 1013-mb total pressure. N2/Ar ratios are in precise agreement with the solubility ratios of Benson and Parker. The range and covariance of N2 and Ar variations are consistent with atmospheric pressure variations over the sea. Oxygen values are systematically higher than the ‘classical’ Winkler values by 3.7%. No evidence was found for the large supersaturation of argon reported by Bieri, Koide, and Goldberg in 1966 and the Ar-T-S relationships are inconsistent with their vertical mixing model. Small increases in a saturation anomaly are core properties of water types formed by subsurface mixing and are associated with T-S slope changes; these effects were found in Antarctic and North Pacific Intermediate water. An upper limit of 8.7% excess helium was found at a depth of 1000 meters at 33°S latitude.

Craig, H, Weiss RF.  1968.  Argon concentrations in the ocean: A discussion. Earth and Planetary Science Letters. 5:175-&.   10.1016/s0012-821x(68)80036-6   AbstractWebsite

Because of the importance of argon as a conservative gas tracer in the oceans and as the only rare gas measured both by mass spectrometry and gas chromatography, critical evaluation and comparison of data measured by the two methods is essential. The use of isotope dilution methods in the mass-spectrometric analyses has produced essentially identical precision and accuracy as have been obtained by gas chromatography and the latest Pacific data are in good agreement, especially below 1000 meters depth. The recent data of Bieri et al. provide significant new evidence for the processes we have proposed as responsible for extrema in the saturation anomalies. The data are also consistent with calculations of diffusional losses of the rare gases in northward flowing bottom water in the Pacific.

Craig, H, Weiss RF.  1970.  The GEOSECS 1969 Intercalibration Station: Introduction, hydrographic features, and total CO2-O2 relationships. Journal of Geophysical Research. 75:7641-7647., Washington, DC, United States (USA): American Geophysical Union, Washington, DC   10.1029/JC075i036p07641   AbstractWebsite

The temperature, salinity, dissolved oxygen, and shipboard chromatograph ΣCO2 data from the 1969 Geosecs station are summarized. Vertical diffusion-advection model parameters calculated from the ΣCO2 and O2 data, by using the mixing parameters obtained from temperature and salinity, give approximately equal mean CO2 production and O2 consumption rates over the deep-water column.

Craig, H, Weiss RF.  1971.  Dissolved gas saturation anomalies and excess helium in the ocean. Earth and Planetary Science Letters. 10:289-296.   10.1016/0012-821x(71)90033-1   AbstractWebsite

New solubility measurements have been made for helium and neon in seawater; the results (published elsewhere) show that neon is actually supersaturated in the ocean, rather than generally undersaturated as indicated by previous data. The pattern of He-Ne-Ar saturation anomalies, based on the new solubility data, shows the presence of an injected “atmospheric component” in Atlantic surface and deep waters and in Pacific deep waters, ranging from 0.5 to 1 ml of air (STP)/kg seawater. Nitrogen-argon relationships in the deep Pacific are also consistent with this effect. In addition to T and P, a third parameter is thus required for the study of saturation anomalies. The magnitude of the injected air fraction accounts for all of the “excess He” in Atlantic Deep Water and about 60% of the excess in the Pacific. The non-atmospheric excess He in the Pacific corresponds to an anomaly of 3%, presumably radiogenic and primordial helium.

Cunnold, DM, Weiss RF, Prinn RG, Hartley D, Simmonds PG, Fraser PJ, Miller B, Alyea FN, Porter L.  1997.  GAGE/AGAGE measurements indicating reductions in global emissions of CCl3F and CCl2F2 in 1992-1994. Journal of Geophysical Research-Atmospheres. 102:1259-1269.   10.1029/96jd02973   AbstractWebsite

Global Atmospheric Gases Experiment/Advanced GAGE (GAGE/AGAGE) observations of CCl3F indicate that global concentrations of this compound reached a maximum in 1993 and decayed slightly in 1994; CCl2F2 concentrations increased approximately 7 ppt in both 1993 and 1994. The observations suggest that world emissions in these two years were smaller than industry production figures would suggest and have decreased faster than expected under the Montreal Protocol and its amendments. An analysis of regional pollution events at the Mace Head site suggest that industry may be underestimating the decline of emissions in Europe. It is argued, however, that the decline in European emissions is not biasing the background Mace Head measurements (or the GAGE global averages). Combining the chlorofluorocarbon measurements, including CCl2FCClF2, with GAGE/AGAGE measured global decreases in CH3CCl3 and CCl4 after 1992 and with Cape Grim archived air measurements of CHClF2, the measurements suggest that anthropogenic atmospheric chlorine loading from these six gases maximized in 1992 at 2.95 +/- 0.04 ppb and that it had decreased by 0.02 +/- 0.01 ppb by the beginning of 1995.

Cunnold, DM, Steele LP, Fraser PJ, Simmonds PG, Prinn RG, Weiss RF, Porter LW, O'Doherty S, Langenfelds RL, Krummel PB, Wang HJ, Emmons L, Tie XX, Dlugokencky EJ.  2002.  In situ measurements of atmospheric methane at GAGE/AGAGE sites during 1985-2000 and resulting source inferences. Journal of Geophysical Research-Atmospheres. 107   10.1029/2001jd001226   AbstractWebsite

[1] Continuous measurements of methane since 1986 at the Global Atmospherics Gases Experiment/Advanced Global Atmospherics Gases Experiment (GAGE/AGAGE) surface sites are described. The precisions range from approximately 10 ppb at Mace Head, Ireland, during GAGE to better than 2 ppb at Cape Grim, Tasmania, during AGAGE (i.e., since 1993). The measurements exhibit good agreement with coincident measurements of air samples from the same locations analyzed by Climate Monitoring and Diagnostics Laboratory (CMDL) except for differences of approximately 5 ppb before 1989 (GAGE lower) and about 4 ppb from 1991 to 1995 (GAGE higher). These results are obtained before applying a factor of 1.0119 to the GAGE/AGAGE values to place them on the Tohoku University scale. The measurements combined with a 12-box atmospheric model and an assumed atmospheric lifetime of 9.1 years indicates net annual emissions (emissions minus soil sinks) of 545 Tg CH4 with a variability of only +/-20 Tg from 1985 to 1997 but an increase in the emissions in 1998 of 37 +/- 10 Tg. The effect of OH changes inferred by Prinn et al. [2001] is to increase the estimated methane emissions by approximately 20 Tg in the mid-1980s and to reduce them by 20 Tg in 1997 and by more thereafter. Using a two-dimensional (2-D), 12-box model with transport constrained by the GAGE/AGAGE chlorofluorocarbon measurements, we calculate that the proportion of the emissions coming from the Northern Hemisphere is between 73 and 81%, depending on the OH distribution used. However, this result includes an adjustment of 5% derived from a simulation of the 2-D estimation procedure using the 3-D MOZART model. This adjustment is needed because of the very different spatial emission distributions of the chlorofluorocarbons and methane which makes chlorofluorocarbons derived transport rates inaccurate for the 2-D simulation of methane. The 2-D model combined with the annual cycle in OH from Spivakovsky et al. [2000] provide an acceptable fit to the observed 12-month cycles in methane. The trend in the amplitude of the annual cycle of methane at Cape Grim is used to infer a trend in OH in 30degrees-90degreesS of 0 +/- 5% per decade from 1985 to 2000, in qualitative agreement with Prinn et al. [2001] for the Southern Hemisphere.

Cunnold, DM, Fraser PJ, Weiss RF, Prinn RG, Simmonds PG, Miller BR, Alyea FN, Crawford AJ.  1994.  Global trends and annual releases of CCl3F and CCl2F2 estimated from ALE/GAGE and other measurements from July 1978 to June 1991. Journal of Geophysical Research-Atmospheres. 99:1107-1126.   10.1029/93jd02715   AbstractWebsite

Thirteen years of Atmospheric Lifetime Experiment/Global Atmospheric Gases Experiment CCl3F and CCl2F2 measurements at five remote, surface, globally distributed sites are analyzed. Comparisons are made against shipboard measurements by the Scripps Institution of Oceanography group and archived air samples collected at Cape Grim, Tasmania, since 1978. CCl3F in the lower troposphere was increasing at an average rate of 9.2 ppt/yr over the period July 1978 to June 1988. CCl2F2 was increasing at an average 17.3 ppt/yr in the lower troposphere over the same period. However, between July 1988 and June 1991 the increases of CCl3F and CCl2F2 in this region have averaged just 7.0 ppt/yr and 15.7 ppt/yr, respectively. The rate of increase has been decreasing 2.4 ppt/yr and 2.9 ppt/yr(2) over this 3-year period. Based on a recent scenario of the global releases of these compounds and using the new calibration scale SIO 1993, the equilibrium lifetimes are estimated to be 44(-10)(+17) and 180(_81)(+820) years for CCl3F and CCl2F2, respectively. Using these lifetime estimates and a two-dimensional model, it is estimated that global releases of these two chlorofluorocarbons in 1990 were 249+/-28 x 10(6) kg for CCl3F and 366+/-30 x 10(6) kg for CCl2F2. It is also estimated that combined releases of these chlorofluorocarbons in 1990 were 21+/-5% less than those in 1986.