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Walker, SJ, Weiss RF, Salameh PK.  2000.  Reconstructed histories of the annual mean atmospheric mole fractions for the halocarbons CFC-11, CFC-12, CFC-113, and carbon tetrachloride. Journal of Geophysical Research-Oceans. 105:14285-14296.   10.1029/1999jc900273   AbstractWebsite

Annual mean mixing ratios for the halocarbons CFC-11 (CCl3F), CFC-12 (CCl2F2), CFC-113 (CClF2CCl2F), and carbon tetrachloride (CCl4) have been determined from their first year of industrial production through 1998. From the late 1970s (in the case of CFC-11 and CFC-12) or early 1980s tin the case of CFC-113 and carbon tetrachloride) the reported mixing ratios have been determined from experimental observations made by the Atmospheric Lifetime Experiment/Global Atmospheric Gases Experiment/Advanced Global Atmospheric Gases Experiment program. For years prior to these times we have used estimates of industrial emissions and atmospheric lifetimes to calculate historic concentrations. The likely error bounds of the annual mean values are also reported here. Errors in the annual mean mixing ratio may primarily be a result of incorrect industrial emissions data, an incorrect atmospheric lifetime,or uncertainty in the ALE/GAGE/AGAGE observations. Each of these possible sources of error has been considered separately. These results show that atmospheric concentrations for each of these compounds have experienced a rapid rise in the early part of their production. Tt is only within the past decade that rise rates have decreased sharply and (except in the case of CFC-12) in the past few years that atmospheric concentrations have begun to decrease. The uncertainties in the reconstructed histories are a similar proportion for each of the chlorofluorocarbons (<4% for most of the history). However, uncertainty in the history of carbon tetrachloride is much greater (up to 12%, and this is mainly the result of poor knowledge of CCl4 emissions.

Warner, MJ, Weiss RF.  1985.  Solubilities of chlorofluorocarbons 11 and 12 in water and seawater. Deep-Sea Research Part a-Oceanographic Research Papers. 32:1485-1497.   10.1016/0198-0149(85)90099-8   AbstractWebsite

The solubilities of dilute mixtures of the chlorofluorocarbons CCl3F (CFC-11) and CCl2F2 (CFC-12) in pure water and seawater over the temperature range 0 to 40°C have been measured by gas chromatography. The data have been fitted to equations in temperature and salinity of the form used previously to fit the solubilities of other gases. The fitted values have an estimated accuracy of ∼1.5% and a relative precision of ∼0.7% for both chlorofluorocarbons. The nonideal behavior of these compounds in dilute air mixtures is discussed, and their solubilities from a water-saturated atmosphere are presented in parametric form.

Warner, MJ, Weiss RF.  1992.  Chlorofluoromethanes in South Atlantic Antarctic Intermediate Water. Deep-Sea Research Part a-Oceanographic Research Papers. 39:2053-2075.   10.1016/0198-0149(92)90013-j   AbstractWebsite

Distributions of the dissolved atmospheric chlorofluoromethanes (CFMs) F-11 and F-12 in the South Atlantic Ocean are used to study the ventilation and circulation of Antarctic Intermediate Water (AAIW). CFM distributions on an isopycnal surface representative of AAIW are consistent with recently ventilated water entering the subtropical gyre in the southwestern Atlantic and then being advected anticyclonically around this gyre. The westward-flowing northern limb of the gyre apparently divides near the coast of South America with some water flowing southward to recirculate in the gyre, and the balance flowing northward along the coast of Brazil. At the equator this northward current divides again with one branch going eastward along the equator and the other continuing into the Northern Hemisphere. In the eastern tropical Atlantic, the CFM concentrations on this isopycnal surface in the cyclonic gyre are extremely low between the subtropical gyre and the equatorial tongue. Along the prime meridian, the F-11 and F-12 concentrations on the 27.2 sigma(theta) isopycnal surface between the mixed layer outcrop and the northern edge of the subtropical gyre are fitted to a one-dimensional advection-diffusion model. This model assumes that the CFMs enter the subtropical gyre solely by northward diffusion from the mixed layer outcrop to the southern edge of the subtropical gyre, and that their distributions within the gyre are controlled by both advective and diffusive processes. Velocity and eddy diffusion coefficients are calculated from a least-squares fit to the data. These values are then used to calculate a mean oxygen consumption rate which is consistent with rates calculated using models of other time-dependent geochemical tracers.

Warner, MJ, Bullister JL, Wisegarver DP, Gammon RH, Weiss RF.  1996.  Basin-wide distributions of chlorofluorocarbons CFC-11 and CFC-12 in the north Pacific: 1985-1989. Journal of Geophysical Research-Oceans. 101:20525-20542.   10.1029/96jc01849   AbstractWebsite

All of the dissolved chlorofluorocarbon measurements made between 1985 and 1989 along several long zonal and meridional hydrographic sections in the North Pacific are presented in this manuscript. Chlorofluorocarbon (CFC) concentrations are displayed as functions of depth and density along the sections. Over much of the region studied, dissolved CFCs are observed to have penetrated to densities greater than those that outcrop at the surface in the North Pacific (sigma(theta) > 26.8). Maxima in CFC concentration are associated with remnant winter mixed layers and with mode waters. When the observed CFC concentrations from these sections are normalized to a common date and mapped onto five density surfaces in the North Pacific, it becomes apparent that the Sea of Okhotsk is an important location for the ventilation of the intermediate waters of the North Pacific. The CFC observations are used together with hydrographic data to study the pathways and timescales of circulation and ventilation processes in the upper and intermediate waters of the North Pacific. Using models of the increases of these compounds as a function of time, CFC ''apparent ages'' are calculated on these isopycnal surfaces. The CFC apparent ages are used together with observed apparent oxygen utilization to estimate oxygen utilization rates along these sections.

Waugh, DW, Vollmer MK, Weiss RF, Haine TWN, Hall TM.  2002.  Transit time distributions in Lake Issyk-Kul. Geophysical Research Letters. 29   10.1029/2002gl016201   AbstractWebsite

[1] Measurements of sulfur hexafluoride (SF6)and chlorofluorocarbons (CFCs) are used to constrain the timescales for deep-water renewal in Lake Issyk-Kul. As these tracers have different tropospheric histories their combination provides more transport information than one tracer alone. In particular, from these measurements the mean, Gamma, and standard deviation, sigma, of the distributions of transit times since water made last contact with the surface can be tightly constrained. Gamma is older than the age determined from SF6 and younger than the ages from the CFCs, and increases from around 4 yrs at 200 m to around 10.5 yrs at the deepest location (655 m). sigma also increases with depth and equals around 0.7 to 0.8 Gamma, which corresponds to large ranges of transit times, and implies mixing processes play a major role in the transport. The approach used can also be applied to similar tracer measurements in the oceans and groundwaters to constrain transport in these geophysical systems.

Weiss, RF, Kirsten OH, Ackermann R, Ramo S.  1977.  Free vehicle instrumentation for the in-situ measurement of processes controlling the formation of deep-sea ferromanganese nodules. OCEANS '77 Conference Record. , New York, N.Y., United States (USA): Inst. Electric. and Electron. Eng., New York, N.Y.   10.1109/OCEANS.1977.1154352   Abstract

This paper describes the free vehicle instrumentation under development for the Manganese Nodule Program (MANOP) of the International Decade for Ocean Exploration (IDOE). Principal emphasis is being placed on the MANOP Bottom Lander, a device designed to carry out in situ chemical flux experiments at the seawater-sediment interface at depths up to 6 km. This device will collect time-series water samples from three separate bottom chamber experiments, each of which can be spiked with various chemical and radioisotopic tracers. The device will also make oxygen and pH measurements in each chamber and will take box core samples under each chamber before returning to the surface. All operations will be microprocessor-controlled with data storage capability and with an acoustic data-link to the surface. Deployments will be for periods of up to 1 year.

Weiss, RF.  1970.  Helium isotope effect in solution in water and seawater. Science. 168:247-248.   10.1126/science.168.3928.247   AbstractWebsite

The isotope effect in the solution of helium in water from 0° to 40°C has been determined by microgasometric measurements of the solubilities of pure helium-3 and helium4. At 0°C helium-3 is less soluble than helium-4 in both distilled water and sea-water by 1.2 percent. The observed fractionation factor is 0.988±0.002 at 0°C and appears to decrease with increasing temperature at the rate of 0.0001 per degree Centigrade, although the existence of this trend is of limited statistical certainty. The measured isotope effect is in agreement with the ratio of helium-3 to helium-4 in surface ocean water reported by Clarke, Beg, and Craig.

Weiss, RF, Keeling CD, Craig H.  1981.  The determination of tropospheric nitrous oxide. Journal of Geophysical Research-Oceans and Atmospheres. 86:7197-7202.   10.1029/JC086iC08p07197   AbstractWebsite

A two-step technique, in which the N2O/CO2 ratio is measured by ultrasonic phase-shift gas chromatography and the dry air CO2 concentration is measured by nondispersive infrared analysis, has been developed for the determination of the mole fraction of nitrous oxide in dry air. The N2O concentration is given by the product of these two independent measurements and has a precision (±1 standard deviation) ranging between 0.3 and 0.5%. The absence of systematic errors has been verified by extensive standard intercomparisons and by independent cross checks of the sample extraction procedures. The results of extensive measurements by this technique, reported in a companion paper, fix the mean tropospheric dry air mole fraction of nitrous oxide in the northern hemisphere as of January 1, 1978 at 300.2±0.6 parts per billion, including systematic uncertainties.

Weiss, RF.  1974.  Carbon dioxide in water and seawater: the solubility of a non-ideal gas. Marine Chemistry. 2:203-215.   10.1016/0304-4203(74)90015-2   Abstract

New measurements of the solubility of carbon dioxide in water and seawater confirm the accuracy of the measurements of Murray and Riley, as opposed to those of Li and Tsui. Corrections for non-ideal behavior in the gas phase and for dissociation in distilled water are required to calculate solubility coefficients from these sets of data. Equations for the solubilities of real gases are presented and discussed. Solubility coefficients for carbon dioxide in water and seawater are calculated for the data of Murray and Riley, and are fitted to equations in temperature and salinity of the form used previously to fit the solubilities of other gases.

Weiss, RF.  2002.  Nitrous Oxide. The encyclopedia of global change : environmental change and human society. 2( Goudie AS, Cuff DJ, Eds.).:140-141., Oxford: Oxford University Press Abstract
Weiss, RF.  1991.  Transient tracers in the ocean, tropical Atlantic study: chlorofluorocarbon measurements. Scripps Institution of Oceanography Reference Series. :159., San Diego; La Jolla: University of California ; Scripps Institution of Oceanography Abstract
Weiss, RF, Price BA.  1980.  Nitrous oxide solubility in water and seawater. Marine Chemistry. 8:347-359.   10.1016/0304-4203(80)90024-9   AbstractWebsite

The solubility of nitrous oxide in pure water and seawater has been measured microgasometrically over the range 0–40°C. The data have been corrected for nonideality and are fitted to equations in temperature and salinity of the form used previously to fit the solubilities of other gases. The fitted values have a precision of 0.1% and an estimated accuracy of 0.3%. The nonideal behavior of nitrous oxide—air mixtures is discussed, and the solubility of atmospheric nitrous oxide is presented in parametric form. A similar parametric representation for the solubility of atmospheric carbon dioxide is given in the Appendix.

Weiss, RF.  1971.  Solubility of helium and neon in water and seawater. Journal of Chemical and Engineering Data. 16:235-241.   10.1021/je60049a019   AbstractWebsite

Sulfur hexafluoride (SF6) has been measured at Cape Grim since 1978 via a combination of in situ and flask measurements, including measurements on the Cape Grim air archive. The long-term growth rate of SF6 as observed at Cape Grim has increased from 0.1 ppt yr-1 in the late 1970s to 0.24 ppt yr-1 in the mid-1990s. Since then the growth rate has remained relatively constant at 0.23±0.02 ppt yr-1, indicating relatively constant global emissions (±10 %) since 1995. Pollution episodes at Cape Grim have been used to estimate regional (Melbourne and environs) and Australian emissions of SF6 at 3±1.5 and 15±7.5 tonnes yr-1 during 2001-2003.

Weiss, RF, Bullister JL, Gammon RH, Warner MJ.  1985.  Atmospheric chlorofluoromethanes in the deep equatorial Atlantic. Nature. 314:608-610.   10.1038/314608a0   AbstractWebsite

Waters that leave the surface of the ocean and enter the subsurface circulation contain concentrations of CCl3F (fluorocarbon-11) and CCl2F2 (fluorocarbon-12), which reflects the temporal increases of these industrially produced compounds in the atmosphere. These chlorofluoromethanes (CFMs) are extremely stable in the troposphere and in natural waters, they have no known natural sources, and their histories of release to the atmosphere are fairly well known1. The atmospheric distributions of CCl3F and CCl2F2 are not strongly dependent on latitude2,3, and their surface water concentrations can be expected to come into relatively rapid solubility equilibrium with the atmosphere4. Recent advances in analytical techniques5,6 have made possible the routine use of these CFMs as oceanic tracers on a decadal timescale. The results we report here are from the first detailed surveys of CCl3F and CCl2F2 distributions in the northern and tropical Atlantic Ocean. They show that CFM-bearing waters originating in the region of the Labrador Sea have reached the Equator in a well-defined western-boundary undercurrent located at a depth of about 1.6 km, in the Upper North Atlantic Deep Water. Using a simple dilution model, we calculate that this water has taken about 23 yr to reach the equatorial region, and has been diluted about five-fold by CFM-free waters.

Weiss, RF, Lonsdale P, Lupton JE, Bainbridge AE, Craig H.  1977.  Hydrothermal plumes in the Galapagos Rift. Nature. 267:600-603.   10.1038/267600a0   AbstractWebsite

ALTHOUGH there is indirect evidence that a major fraction of the heat loss from newly-created lithosphere occurs by convection of seawater through the porous crust1–3, it has proved difficult to locate vents of deep-sea hydrothermal systems by direct measurement of the discharge fluid. Local increases in bottom water temperature up to 0.1 °C have been measured by towing arrays of thermistors a few metres above the axes of active oceanic spreading centres4,5, but these data are ambiguous because small temperature anomalies may have a hydrographic explanation. We report here the first conclusive measurements of modified seawater discharging as buoyant hydrothermal plumes from fissures in young oceanic crust. We obtained samples of hydrothermal plumes in the Galapagos Rift3, albeit after considerable dilution with surrounding bottom-water, and report the first results of the collection and analysis of these samples.

Weiss, RF.  1970.  The solubility of nitrogen, oxygen and argon in water and seawater. Deep-Sea Research. 17:721-735.   10.1016/0011-7471(70)90037-9   AbstractWebsite

Recent precise data on the solubilities of nitrogen, oxygen and argon in distilled water and seawater are fitted to thermodynamically consistent equations by the method of least squares. The temperature dependence of the Bunsen solubility coefficient is treated using the integrated van't Hoff equation. It is shown that the Setchénow relation gives an adequate representation of the salting-out effect. Equations expressing the solubilities of these gases, as a function of temperature and salinity, in units of the Bunsen coefficient, ml/l., and ml/kg are given along with solubility tables in each of these units.

Weiss, RF, Van Woy FA, Salameh PK.  1992.  Surface water and atmospheric carbon dioxide and nitrous oxide observations by shipboard automated gas chromatography : results from expeditions between 1977 and 1990. Scripps Institution of Oceanography Reference Series. :144., La Jolla, Calif.: Scripps Institution of Oceanography, University of California, San Diego Abstract
Weiss, RF, Jahnke RA, Keeling CD.  1982.  Seasonal effects of temperature and salinity on the partial pressure of CO2 in seawater. Nature. 300:511-513.   10.1038/300511a0   AbstractWebsite

The exchange of CO2 between the atmosphere and the sea is of major importance to our understanding of the climatic consequences of anthropogenic CO2. Because the solubility of CO2 and the dissociation of carbonic acid in seawater are modulated by temperature and salinity, the detection of long-term changes in the oceanic carbonate system, first requires that the comparatively large short-term variations in the partial pressure of CO2 should be characterized. We present here the first direct observations of seasonal variations in the partial pressure of CO2 in the subtropical gyres of the North and South Pacific Ocean. These variations compare well with the variations predicted from observed changes in temperature and salinity using empirical equations which do not require the determination of alkalinity or total inorganic carbon, and the agreement is improved by the inclusion of air–sea exchange in the model calculations. Thus we predict that specific alkalinity within the two gyres remains extremely constant, which is confirmed by carbonate equilibrium calculations based on our measurements of total inorganic carbon.

Weiss, RF, Craig H.  1976.  Production of atmospheric nitrous oxide by combustion. Geophysical Research Letters. 3:751-753.   10.1029/GL003i012p00751   AbstractWebsite

Measurements of N2O in the effluent gases from the burning of coal and fuel oil show that these are significant anthropogenic sources of atmospheric N2O. We estimate that the present global production of N2O from these sources is 1.6 Mtons N2O(N) per year and is increasing at a rate of ∼ 3.5% per year. Catalytic converters for the reduction of NO emissions also represent a major potential source of atmospheric N2O.

Weiss, RF, Muhle J, Salameh PK, Harth CM.  2008.  Nitrogen trifluoride in the global atmosphere. Geophysical Research Letters. 35   10.1029/2008gl035913   AbstractWebsite

Background atmospheric abundances and trends of nitrogen trifluoride (NF(3)), a potent anthropogenic greenhouse gas, have been measured for the first time. The mean global tropospheric concentration of NF(3) has risen quasi-exponentially from about 0.02 ppt (parts-per-trillion, dry air mole fraction) at the beginning of our measured record in 1978, to a July 1, 2008 value of 0.454 ppt, with a rate of increase of 0.053 ppt yr(-1), or about 11% per year, and an interhemispheric gradient that is consistent with these emissions occuring overwhelmingly in the Northern Hemisphere, as expected. This rise rate corresponds to about 620 metric tons of current NF(3) emissions globally per year, or about 16% of the poorly-constrained global NF(3) production estimate of 4,000 metric tons yr(-1). This is a significantly higher percentage than has been estimated by industry, and thus strengthens the case for inventorying NF(3) production and for regulating its emissions. Citation: Weiss, R. F., J. Muhle, P. K., Salameh, and C.M. Harth (2008), Nitrogen trifluoride in the global atmosphere, Geophys. Res. Lett., 35, L208121, doi: 10.1029/2008GL035913.

Weiss, RF.  1968.  Piggyback sampler for dissolved gas studies on sealed water samples. Deep-Sea Research. 15:695-699.   10.1016/0011-7471(68)90082-x   AbstractWebsite

A sampler which obtains leak-proof sealed water samples from any depth has been developed for the study of dissolved gases. Closing of the sampler is activated by the tripping of the Nansen bottle to which it is attached. The water collected by the sampler is thus taken at the same time and place at which the Nansen bottle measures thermometric depth and temperature and collects water for measurement of salinity and other properties. Other advantages include ease of operation and low cost. The sampler has been tested at sea under a wide range of conditions.

Weiss, RF, Carmack EC, Koropalov VM.  1991.  Deep-water renewal and biological production in Lake Baikal. Nature. 349:665-669.   10.1038/349665a0   AbstractWebsite

The physics of mixing in deep temperate lakes is strongly constrained by the existence of a temperature of maximum density for fresh water, and by the pressure dependence of that temperature. The world's deepest lake is well suited to the study of such deep-water renewal processes, and also to the determination of the rate of renewal using time-dependent chemical tracers. The mean rates of biological recycling of oxygen, carbon and nutrients for the entire lake can then also be determined.

Weiss, RF.  1981.  Determinations of carbon dioxide and methane by dual catalyst flame ionization chromatography and nitrous oxide by electron capture chromatography. Journal of Chromatographic Science. 19:611-616.   10.1093/chromsci/19.12.611   AbstractWebsite

An automated gas chromatographic (GC) system has been developed for the measurement of carbon dioxide, methane, and nitrous oxide in air and other gases. Carbon dioxide is measured by a flame ionization detector (FID) after conversion to methane in pure hydrogen carrier gas, using palladium and nickel dual catalysts which permit direct on-line injection of oxygen-containing samples. The detector measures methane in the same sample, although the system has not been optimized for this gas. Nitrous oxide is measured in a separate aliquot of the sample using a hot electron capture datector (ECD) and argon-methane carrier gas. Typical relative standard deviations of the calculated results are 0.04% for carbon dioxide, 0.4% for methane, and 0.3% for nitrous oxide.

Weiss, RF, Bucher P, Craig H, Oeschger H.  1972.  Compositional variations of gases in temperate glaciers. Earth and Planetary Science Letters. 16:178-&.   10.1016/0012-821x(72)90186-0   AbstractWebsite

Concentrations of N2, O2, Ar and CO2 in ice from the Aletsch Glacier in the Bernese Alps have been measured by gas chromatography. Newly formed ice at the head of the glacier contains N2, O2 and Ar in roughly atmospheric proportions, whereas the CO2 content is ∼ 50 times greater than in air. Samples from the terminus of the glacier are considerably lower in total gas content, and are depleted in Ar and O2 and enriched in N2 with respect to air. The CO2 of this gas is ∼ 100 times greater than in air. Model calculations show that the N2-O2-Ar relationships are explained by the removal of these gases in solution in meltwater. In the case of CO2, the results indicate that only a small fraction of the CO2 in the ice is present in bubbles, the remainder being distributed within the ice matrix. Adsorption of atmospheric CO2 probably plays a role in determining the concentrations and distribution of CO2 in glacier ice.

Weiss, RF, Price BA.  1989.  Dead Sea gas solubilities. Earth and Planetary Science Letters. 92:7-10.   10.1016/0012-821x(89)90016-2   AbstractWebsite

The solubilities of helium and argon have been measured in Dead Sea brine. A simple model is presented whereby the solubilities of these and other gases in Dead Sea water as functions of temperature and salinity may be closely approximated from existing equations for the solubilities of these gases in pure water and seawater. The salting out per unit mass of Dead Sea salt exceeds that of sea salt by about 9%. The Bunsen solubility coefficients of a number of selected gases in the Dead Sea are about 15–25% of their values in pure water. Parametric equations are given for calculating the equilibrium concentrations of dissolved atmospheric gases in the Dead Sea.