Based on observations of the chlorofluorocarbons CFC-13 (chlorotrifluoromethane), Sigma CFC-114 (combined measurement of both isomers of dichlorotetrafluoroethane), and CFC-115 (chloropentafluoroethane) in atmospheric and firn samples, we reconstruct records of their tropospheric histories spanning nearly 8 decades. These compounds were measured in polar firn air samples, in ambient air archived in canisters, and in situ at the AGAGE (Advanced Global Atmospheric Gases Experiment) network and affiliated sites. Global emissions to the atmosphere are derived from these observations using an inversion based on a 12-box atmospheric transport model. For CFC-13, we provide the first comprehensive global analysis. This compound increased monotonically from its first appearance in the atmosphere in the late 1950s to a mean global abundance of 3.18 ppt (dry-air mole fraction in parts per trillion, pmol mol(-1)) in 2016. Its growth rate has decreased since the mid-1980s but has remained at a surprisingly high mean level of 0.02 ppt yr(-1) since 2000, resulting in a continuing growth of CFC-13 in the atmosphere. Sigma CFC-114 increased from its appearance in the 1950s to a maximum of 16.6 ppt in the early 2000s and has since slightly declined to 16.3 ppt in 2016. CFC-115 increased monotonically from its first appearance in the 1960s and reached a global mean mole fraction of 8.49 ppt in 2016. Growth rates of all three compounds over the past years are significantly larger than would be expected from zero emissions. Under the assumption of unchanging lifetimes and atmospheric transport patterns, we derive global emissions from our measurements, which have remained unexpectedly high in recent years: mean yearly emissions for the last decade (2007-2016) of CFC-13 are at 0.48 +/- 0.15 kt yr(-1) (> 15% of past peak emissions), of 6 CFC-114 at 1.90 +/- 0.84 kt yr(-1) (similar to 10% of peak emissions), and of CFC-115 at 0.80 +/- 0.50 kt yr(-1) (> 5% of peak emissions). Mean yearly emissions of CFC-115 for 2015-2016 are 1.14 +/- 0.50 kt yr(-1) and have doubled compared to the 2007-2010 minimum. We find CFC-13 emissions from aluminum smelters but if extrapolated to global emissions, they cannot account for the lingering global emissions determined from the atmospheric observations. We find impurities of CFC-115 in the refrigerant HFC-125 (CHF2CF3) but if extrapolated to global emissions, they can neither account for the lingering global CFC-115 emissions determined from the atmospheric observations nor for their recent increases. We also conduct regional inversions for the years 2012-2016 for the northeastern Asian area using observations from the Korean AGAGE site at Gosan and find significant emissions for Sigma CFC-114 and CFC-115, suggesting that a large fraction of their global emissions currently occur in northeastern Asia and more specifically on the Chinese mainland.
Wells, K. C.; Millet, D. B.; Bousserez, N.; Henze, D. K.; Griffis, T. J.; Chaliyakunnel, S.; Dlugokencky, E. J.; Saikawa, E.; Xiang, G.; Prinn, R. G.; O'Doherty, S.; Young, D.; Weiss, R. F.; Dutton, G. S.; Elkins, J. W.; Krummel, P. B.; Langenfelds, R.; Steele, L. P.;
Published Date:
2018
Source:
Atmospheric Chemistry and Physics, 18(2), 735-756.
Description:
We present top-down constraints on global monthly N2O emissions for 2011 from a multi-inversion approach and an ensemble of surface observations. The inversions employ the GEOS-Chem adjoint and an array of aggregation strategies to test how well curr...
Raczka, B.; Biraud, S. C.; Ehleringer, J. R.; Lai, C. T.; Miller, J. B.; Pataki, D. E.; Saleska, S. R.; Torn, M. S.; Vaughn, B. H.; Wehr, R.; Bowling, D. R.;
Published Date:
2017
Source:
Journal of Geophysical Research-Biogeosciences, 122(8), 1969-1987.
Description:
The seasonal pattern of the carbon isotope content (delta C-13) of atmospheric CO2 depends on local and nonlocal land-atmosphere exchange and atmospheric transport. Previous studies suggested that the delta C-13 of the net land-atmosphere CO2 flux (d...
Journal of Geophysical Research-Atmospheres, 123(15), 7950-7973.
Description:
In this study, we analyze a set of agroclimatological indices across West Africa and assess their projected changes for the future. We apply the regional climate model CCLM (COnsortium for Small-scale MOdelling in CLimate Mode) with a high spatial re...
Kenagy, H. S.; Sparks, T. L.; Ebben, C. J.; Wooldrige, P. J.; Lopez-Hilfiker, F. D.; Lee, B. H.; Thornton, J. A.; McDuffie, E. E.; Fibiger, D. L.; Brown, S. S.; Montzka, D. D.; Weinheimer, A. J.; Schroder, J. C.; Campuzano-Jost, P.; Day, D. A.; Jimenez, J. L.; Dibb, J. E.; Campos, T.; Shah, V.; Jaegle, L.; Cohen, R. C.;
Published Date:
2018
Source:
Journal of Geophysical Research-Atmospheres, 123(17), 9813-9827.
Description:
Although urban NOx lifetimes have been examined extensively during summertime conditions, wintertime NOx chemistry has been comparatively less studied. We use measurements of NOx and its oxidation products from the aircraft-based WINTER (Wintertime I...
Jarvinen, E.; Ignatius, K.; Nichman, L.; Kristensen, T. B.; Fuchs, C.; Hoyle, C. R.; Hoppel, N.; Corbin, J. C.; Craven, J.; Duplissy, J.; Ehrhart, S.; El Haddad, I.; Frege, C.; Gordon, H.; Jokinen, T.; Kallinger, P.; Kirkby, J.; Kiselev, A.; Naumann, K. H.; Petaja, T.; Pinterich, T.; Prevot, A. S. H.; Saathoff, H.; Schiebel, T.; Sengupta, K.; Simon, M.; Slowik, J. G.; Trostl, J.; Virtanen, A.; Vochezer, P.; Vogt, S.; Wagner, A. C.; Wagner, R.; Williamson, C.; Winkler, P. M.; Yan, C.; Baltensperger, U.; Donahue, N. M.; Flagan, R. C.; Gallagher, M.; Hansel, A.; Kulmala, M.; Stratmann, F.; Worsnop, D. R.; Mohler, O.; Leisner, T.; Schnaiter, M.;
Published Date:
2016
Source:
Atmospheric Chemistry and Physics, 16(7), 4423-4438.
Description:
Under certain conditions, secondary organic aerosol (SOA) particles can exist in the atmosphere in an amorphous solid or semi-solid state. To determine their relevance to processes such as ice nucleation or chemistry occurring within particles requir...
Butler, R.; Palmer, P. I.; Feng, L.; Andrews, S. J.; Atlas, E. L.; Carpenter, L. J.; Donets, V.; Harris, N. R. P.; Montzka, S. A.; Pan, L. L.; Salawitch, R. J.; Schauffler, S. M.;
Published Date:
2018
Source:
Atmospheric Chemistry and Physics, 18(17), 13135-13153.
Description:
We use the GEOS-Chem global 3-D atmospheric chemistry transport model to interpret atmospheric observations of bromoform (CHBr3) and dibromomethane (CH2Br2) collected during the CAST and CONTRAST aircraft measurement campaigns over the western Pacifi...
Fried, A.; Barth, M. C.; Bela, M.; Weibring, P.; Richter, D.; Walega, J.; Li, Y.; Pickering, K.; Apel, E.; Hornbrook, R.; Hills, A.; Riemer, D. D.; Blake, N.; Blake, D. R.; Schroeder, J. R.; Luo, Z. J.; Crawford, J. H.; Olson, J.; Rutledge, S.; Betten, D.; Biggerstaff, M. I.; Diskin, G. S.; Sachse, G.; Campos, T.; Flocke, F.; Weinheimer, A.; Cantrell, C.; Pollack, I.; Peischl, J.; Froyd, K.; Wisthaler, A.; Mikoviny, T.; Woods, S.;
Published Date:
2016
Source:
Journal of Geophysical Research-Atmospheres, 121(12), 7430-7460.
Description:
We have developed semi-independent methods for determining CH2O scavenging efficiencies (SEs) during strong midlatitude convection over the western, south-central Great Plains, and southeastern regions of the United States during the 2012 Deep Convec...
Janssens-Maenhout, G.; Crippa, M.; Guizzardi, D.; Dentener, F.; Muntean, M.; Pouliot, G.; Keating, T.; Zhang, Q.; Kurokawa, J.; Wankmuller, R.; van der Gon, H. D.; Kuenen, J. J. P.; Klimont, Z.; Frost, G.; Darras, S.; Koffi, B.; Li, M.;
Published Date:
2015
Source:
Atmospheric Chemistry and Physics, 15(19), 11411-11432.
Description:
The mandate of the Task Force Hemispheric Transport of Air Pollution (TF HTAP) under the Convention on Long-Range Transboundary Air Pollution (CLRTAP) is to improve the scientific understanding of the intercontinental air pollution transport, to quan...
Brown, S. S.; Dube, W. P.; Tham, Y. J.; Zha, Q. Z.; Xue, L. K.; Poon, S.; Wang, Z.; Blake, D. R.; Tsui, W.; Parrish, D. D.; Wang, T.;
Published Date:
2016
Source:
Journal of Geophysical Research-Atmospheres, 121(5), 2457-2475.
Description:
Nighttime reactions of nitrogen oxides influence ozone, volatile organic compounds, and aerosol and are thus important to the understanding of regional air quality. Despite large emissions and rapid recent growth of nitrogen oxide concentrations, the...
Kim, J.; Johnson, L. E.; Cifelli, R.; Choi, J.; Chandrasekar, V.;
Published Date:
2018
Source:
Water, 10(7), 21.
Description:
Soil moisture retention (SMR) capacity plays a key role in estimating the direct runoff when a multi-pulse storm event occurs. It is very important to know how much SMR will be recovered during the intervals of no rain of a multi-pulse storm. This st...
Fairall, C. W.; Matrosov, S. Y.; Williams, C. R.; Walsh, E. J.;
Published Date:
2018
Source:
Journal of Atmospheric and Oceanic Technology, 35(3), 593-608.
Description:
The NOAA W-band radar was deployed on a P-3 aircraft during a study of storm fronts off the U.S. West Coast in 2015 in the second CalWater (CalWater-2) field program. This paper presents an analysis of measured equivalent radar reflectivity factor Z(...
A 4-year record of aerosol size and hygroscopic growth factor distributions measured at the Department of Energy's Southern Great Plains (SGP) site in Oklahoma, U.S. were used to estimate supersaturation (S)-dependent cloud condensation nuclei concen...
Mahoney, K.; Swales, D.; Mueller, M. J.; Alexander, M.; Hughes, M.; Malloy, K.;
Published Date:
2018
Source:
Journal of Climate, 31(16), 6281-6297.
Description:
Atmospheric rivers (ARs) are well-known producers of precipitation along the U.S. West Coast. Depending on their intensity, orientation, and location of landfall, some ARs penetrate inland and cause heavy rainfall and flooding hundreds of miles from ...
Dimdore-Miles, O. B.; Palmer, P. I.; Bruhwiler, L. P.;
Published Date:
2018
Source:
Atmospheric Chemistry and Physics, 18(24), 17895-17907.
Description:
We consider the utility of the annual inter-polar difference (IPD) as a metric for changes in Arctic emissions of methane (CH4). The IPD has been previously defined as the difference between weighted annual means of CH4 mole fraction data collected a...
Sea surface temperature anomalies (SSTA) in portions of the extratropics are known to recur from one winter to the next without persisting through the intervening summer. Previous studies identified only a limited number of midlatitude regions where ...
Richardson, K.; Asmutis-Silvia, R.; Drinkwin, J.; Gilardi, K. V. K.; Giskes, I.; Jones, G.; O'Brien, K.; Pragnell-Raasch, H.; Ludwig, L.; Antonelis, K.; Barco, S.; Henry, A.; Knowlton, A.; Landry, S.; Mattila, D.; MacDonald, K.; Moore, M.; Morgan, J.; Robbins, J.; van der Hoop, J.; Hogan, E.;
Published Date:
2019
Source:
Marine Pollution Bulletin, 138, 222-229.
Description:
Abandoned, lost or discarded fishing gear (ALDFG) comprises a significant amount of global marine debris, with diverse impacts to marine environments, wildlife, and the fishing industry. Building evidence on ALDFG is critical to holistically understa...
Smith, M.; Stammerjohn, S.; Persson, O.; Rainville, L.; Liu, G. Q.; Perrie, W.; Robertson, R.; Jackson, J.; Thomson, J.;
Published Date:
2018
Source:
Journal of Geophysical Research-Oceans, 123(5), 3164-3185.
Description:
High-resolution measurements of the air-ice-ocean system during an October 2015 event in the Beaufort Sea demonstrate how stored ocean heat can be released to temporarily reverse seasonal ice advance. Strong on-ice winds over a vast fetch caused mixi...
Chakraborty, A.; Ervens, B.; Gupta, T.; Tripathi, S. N.;
Published Date:
2016
Source:
Journal of Geophysical Research-Atmospheres, 121(8), 4317-4332.
Description:
Size-resolved fog water samples were collected in two consecutive winters at Kanpur, a heavily polluted urban area of India. Samples were analyzed by an aerosol mass spectrometer after drying and directly in other instruments. Residues of fine fog dr...
Kim, P. S.; Jacob, D. J.; Fisher, J. A.; Travis, K.; Yu, K.; Zhu, L.; Yantosca, R. M.; Sulprizio, M. P.; Jimenez, J. L.; Campuzano-Jost, P.; Froyd, K. D.; Liao, J.; Hair, J. W.; Fenn, M. A.; Butler, C. F.; Wagner, N. L.; Gordon, T. D.; Welti, A.; Wennberg, P. O.; Crounse, J. D.; St. Clair, J. M.; Teng, A. P.; Millet, D. B.; Schwarz, J. P.; Markovic, M. Z.; Perring, A. E.;
Heiblum, R. H.; Altaratz, O.; Koren, I.; Feingold, G.; Kostinski, A. B.; Khain, A. P.; Ovchinnikov, M.; Fredj, E.; Dagan, G.; Pinto, L.; Yaish, R.; Chen, Q.;
Published Date:
2016
Source:
Journal of Geophysical Research-Atmospheres, 121(11), 6336-6355.
Description:
We study the evolution of warm convective cloud fields using large eddy simulations of continental and trade cumulus. Individual clouds are tracked a posteriori from formation to dissipation using a 3-D cloud-tracking algorithm, and results are prese...
Prinn, R. G.; Weiss, R. F.; Arduini, J.; Arnold, T.; DeWitt, H. L.; Fraser, P. J.; Ganesan, A. L.; Gasore, J.; Harth, C. M.; Hermansen, O.; Kim, J.; Krummel, P. B.; Li, S. L.; Loh, Z. M.; Lunder, C. R.; Maione, M.; Manning, A. J.; Miller, B.; Mitrevski, B.; Muhle, J.; O'Doherty, S.; Park, S.; Reimann, S.; Rigby, M.; Saito, T.; Salameh, P. K.; Schmidt, R.; Simmonds, P. G.; Steele, L. P.; Vollmer, M. K.; Wang, R. H.; Yao, B.; Yokouchi, Y.; Young, D.; Zhou, L. X.;
Published Date:
2018
Source:
Earth System Science Data, 10(2), 985-1018.
Description:
We present the organization, instrumentation, datasets, data interpretation, modeling, and accomplishments of the multinational global atmospheric measurement program AGAGE (Advanced Global Atmospheric Gases Experiment). AGAGE is distinguished by its...
Vollmer, Martin K.; Bernard, François; Mitrevski, Blagoj; Steele, L. Paul; Trudinger, Cathy M.; Reimann, Stefan; Langenfelds, Ray L.; Krummel, Paul B.; Fraser, Paul J.; Etheridge, David M.; Curran, Mark A. J.; Burkholder, James B.;
Published Date:
2019
Source:
Atmos. Chem. Phys., 19, 3481–3492, 2019
Description:
The first atmospheric observations of octafluorooxolane (octafluorotetrahydrofuran, c-C4F8O), a persistent greenhouse gas, are reported. In addition, a complementary laboratory study of its most likely atmospheric loss processes, its infrared absorpt...