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Rhew, RC, Miller BR, Weiss RF.  2000.  Natural methyl bromide and methyl chloride emissions from coastal salt marshes. Nature. 403:292-295.   10.1038/35002043   AbstractWebsite

Atmospheric methyl bromide (CH3Br) and methyl chloride (CH3Cl), compounds that are involved in stratospheric ozone depletion, originate from both natural and anthropogenic sources. Current estimates of CH3Br and CH3Cl emissions from oceanic sources, terrestrial plants and fungi, biomass burning and anthropogenic inputs do not balance their losses owing to oxidation by hydroxyl radicals, oceanic degradation, and consumption in soils, suggesting that additional natural terrestrial sources may be important(1). Here we show that CH3Br and CH3Cl are released to the atmosphere from all vegetation zones of two coastal salt marshes. We see very large fluxes of CH3Br and CH3Cl per unit area: up to 42 and 570 mu mol m(-2) d(-1), respectively. The fluxes show large diurnal, seasonal and spatial variabilities, but there is a strong correlation between the fluxes of CH3Br and those of CH3Cl, with an average molar flux ratio of roughly 1:20. If our measurements are typical of salt marshes globally, they suggest that such ecosystems, even though they constitute less than 0.1% of the global surface area(2), may produce roughly 10% of the total fluxes of atmospheric CH3Br and CH3Cl.

Arnold, T, Harth CM, Mühle J, Manning AJ, Salameh PK, Kim J, Ivy DJ, Steele PL, Petrenko VV, Severinghaus JP, Baggenstos D, Weiss RF.  2013.  Nitrogen trifluoride global emissions estimated from updated atmospheric measurements. Proceedings of the National Academy of Sciences.   10.1073/pnas.1212346110   AbstractWebsite

Nitrogen trifluoride (NF3) has potential to make a growing contribution to the Earth’s radiative budget; however, our understanding of its atmospheric burden and emission rates has been limited. Based on a revision of our previous calibration and using an expanded set of atmospheric measurements together with an atmospheric model and inverse method, we estimate that the global emissions of NF3 in 2011 were 1.18 ± 0.21 Gg⋅y−1, or ∼20 Tg CO2-eq⋅y−1 (carbon dioxide equivalent emissions based on a 100-y global warming potential of 16,600 for NF3). The 2011 global mean tropospheric dry air mole fraction was 0.86 ± 0.04 parts per trillion, resulting from an average emissions growth rate of 0.09 Gg⋅y−2 over the prior decade. In terms of CO2 equivalents, current NF3 emissions represent between 17% and 36% of the emissions of other long-lived fluorinated compounds from electronics manufacture. We also estimate that the emissions benefit of using NF3 over hexafluoroethane (C2F6) in electronics manufacture is significant—emissions of between 53 and 220 Tg CO2-eq⋅y−1 were avoided during 2011. Despite these savings, total NF3 emissions, currently ∼10% of production, are still significantly larger than expected assuming global implementation of ideal industrial practices. As such, there is a continuing need for improvements in NF3 emissions reduction strategies to keep pace with its increasing use and to slow its rising contribution to anthropogenic climate forcing.

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.  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
Thompson, RL, Chevallier F, Crotwell AM, Dutton G, Langenfelds RL, Prinn RG, Weiss RF, Tohjima Y, Nakazawa T, Krummel PB, Steele LP, Fraser P, O'Doherty S, Ishijima K, Aoki S.  2014.  Nitrous oxide emissions 1999 to 2009 from a global atmospheric inversion. Atmospheric Chemistry and Physics. 14:1801-1817.   10.5194/acp-14-1801-2014   AbstractWebsite

N2O surface fluxes were estimated for 1999 to 2009 using a time-dependent Bayesian inversion technique. Observations were drawn from 5 different networks, incorporating 59 surface sites and a number of ship-based measurement series. To avoid biases in the inverted fluxes, the data were adjusted to a common scale and scale offsets were included in the optimization problem. The fluxes were calculated at the same resolution as the transport model (3.75 degrees longitude x 2.5 degrees latitude) and at monthly time resolution. Over the 11-year period, the global total N2O source varied from 17.5 to 20.1 Tg a(-1) N. Tropical and subtropical land regions were found to consistently have the highest N2O emissions, in particular in South Asia (20 +/- 3% of global total), South America (13 +/- 4 %) and Africa (19 +/- 3 %), while emissions from temperate regions were smaller: Europe (6 +/- 1 %) and North America (7 +/- 2 %). A significant multi-annual trend in N2O emissions (0.045 Tg a(-2) N) from South Asia was found and confirms inventory estimates of this trend. Considerable interannual variability in the global N2O source was observed (0.8 Tg a(-1) N, 1 standard deviation, SD) and was largely driven by variability in tropical and subtropical soil fluxes, in particular in South America (0.3 Tg a(-1) N, 1 SD) and Africa (0.3 Tg a(-1) N, 1 SD). Notable variability was also found for N2O fluxes in the tropical and southern oceans (0.15 and 0.2 Tg a(-1) N, 1 SD, respectively). Interannual variability in the N2O source shows some correlation with the El Nino-Southern Oscillation (ENSO), where El Nino conditions are associated with lower N2O fluxes from soils and from the ocean and vice versa for La Nina conditions.

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.

Landrum, LL, Gammon RH, Feely RA, Murphy PP, Kelly KC, Cosca CE, Weiss RF.  1996.  North Pacific Ocean CO2 disequilibrium for spring through summer, 1985-1989. Journal of Geophysical Research-Oceans. 101:28539-28555.   10.1029/96jc02100   AbstractWebsite

Extensive measurements of CO2 fugacity in the North Pacific surface ocean and overlying atmosphere during the years 1985-1989 are synthesized and interpreted to yield a basin-wide estimate of Delta fCO(2). The observations, taken from February through early September, suggest that the subtropical and subarctic North Pacific is a small sink for atmospheric CO2 (0.07 to 0.2 Gton C (half year)(-1) for the region north of 15 degrees N). Objective analysis techniques are used to estimate uncertainty fields resulting from constructing basin-wide contours of oceanic fCO(2) on the basis of individual cruise transects. The uncertainties are significant and imply that future sampling programs need to recognize that estimating oceanic uptake of anthropogenic CO2 from ship-transect observations of oceanic fCO(2) alone will require very extensive sampling.

Petrenko, VV, Severinghaus JP, Brook EJ, Muhle J, Headly M, Harth CM, Schaefer H, Reeh N, Weiss RF, Lowe D, Smith AM.  2008.  A novel method for obtaining very large ancient air samples from ablating glacial ice for analyses of methane radiocarbon. Journal of Glaciology. 54:233-244.   10.3189/002214308784886135   AbstractWebsite

We present techniques for obtaining large (similar to 100 L STP) samples of ancient air for analysis of (14)C of methane ((14)CH(4)) and other trace constituents. Paleoatmospheric (14)CH(4) measurements should constrain the fossil fraction of past methane budgets, as well as provide a definitive test of methane clathrate involvement in large and rapid methane concentration ([CH(4)]) increases that accompanied rapid warming events during the last deglaciation. Air dating to the Younger Dryas-Preboreal and Oldest Dryas-Bolling abrupt climatic transitions was obtained by melt extraction from old glacial ice outcropping at an ablation margin in West Greenland. The outcropping ice and occluded air were dated using a combination of delta(15)N of N(2), delta(18)O of O(2), delta(18)O(ice) and [CH(4)] measurements. The [CH(4)] blank of the melt extractions was <4 ppb. Measurements of delta(18)O and delta(15)N indicated no significant gas isotopic fractionation from handling. Measured Ar/N(2), CFC-11 and CFC-12 in the samples indicated no significant contamination from ambient air. Ar/N(2), Kr/Ar and Xe/Ar ratios in the samples were used to quantify effects of gas dissolution during the melt extractions and correct the sample [CH(4)]. Corrected [CH(4)] is elevated over expected values by up to 132 ppb for most samples, suggesting some in situ CH(4) production in ice at this site.

Edmond, JM, Stallard RF, Craig H, Craig V, Weiss RF, Coulter GW.  1993.  Nutrient chemistry of the water column of Lake Tanganyika. Limnology and Oceanography. 38:725-738. AbstractWebsite

Lake Tanganyika shows permanent thermal stratification with deep-water temperatures that have been stable over the period of observation (since 1939). The lake is anoxic below approximately 150-m depth. In general the nutrients show Redfield behavior save in the deep waters of the northern basin where large excesses of phosphate and ammonia are present. Bacterial disproportionation of organic material probably plays an important role in producing these excesses. Inorganic desorption from fluvial detritus is also a possible source of excess phosphate in deep waters. The oxic-anoxic boundary at approximately 150 m is a sink for all forms of fixed nitrogen. Thus the nutrient budget of the lake probably involves fixation of nitrogen in the surface layer in addition to substantial inputs from rainfall and runoff, with the phosphate supplied by vertical mixing. Because these processes are in approximate balance under present conditions, the productivity of the lake must be very sensitive to changes in climatic forcing.