ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-11-1379-2011 Sensitivity of stratospheric Br<sub>y</sub> to uncertainties in very short lived substance emissions and atmospheric transport Schofield R. 1 Fueglistaler S. 2 3 Wohltmann I. 1 Rex M. 1 Alfred Wegener Institute, Potsdam, Germany Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge, UK now at: Department of Geosciences, Princeton University, New Jersey, USA 16 02 2011 11 4 1379 1392 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys.net/11/1379/2011/acp-11-1379-2011.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/11/1379/2011/acp-11-1379-2011.pdf

We evaluate the sensitivity of Br<sub>y</sub> entering the stratosphere with a simplified model that allows calculations over a wide parameter range for parameters that are currently poorly quantified. The model examines the transport process uncertainties in the source concentrations and lifetimes, in the convective parameterization and in the inorganic bromine washout process due to dehydration. Source concentrations at the surface and lifetimes were found to have a slight effect on the resultant Br<sub>y</sub> (1 ppt), however this was highly dependent upon, with increasing significance, the BL component of convectively delivered air. Efficiency of convective delivery of boundary layer (BL) air to the tropical tropopause layer (TTL) along with washout at the CPT were found to substantially affect Br<sub>y</sub> at 400 K – altering the delivered Br<sub>y</sub> by 3.3 ppt and 2.9 ppt, respectively. We find that the results critically depend on free tropospheric bromine source gas concentrations due to dilution of convective updrafts, and the processes that control free tropospheric bromine source gas concentrations require further attention.

 References Andreae, M O., Atlas, E., Harris, G W., Helas, G., deKock, A., Koppmann, R., Maenhaut, W., Man\o, S., Pollock, W H., Rudolph, J., Scharffe, D., Schebeske, G., and Welling, M.: Methyl halide emissions from savanna fires in southern Africa, J. Geophys. Res., 101, D19, 23603–23613, 1996. Aschmann, J., Sinnhuber, B M., Atlas, E L., and Schauffler, S M.: Modeling the transport of very short-lived substances into the tropical upper troposphere and lower stratosphere, Atmos. Chem. Phys., 9, 23, 9237–9247, http://dx.doi.org/10.5194/acp-9-9237-2009doi:10.5194/acp-9-9237-2009, 2009. Aschmann, J., Sinnhuber, B M., Chipperfield, M P., and Hossaini, R.: Impact of deep convection and dehydration on bromine loading in the upper troposphere and lower stratosphere, Atmos. Chem. Phys. Discuss., 11, 121–162, http://dx.doi.org/10.5194/acpd-11-121-2011doi:10.5194/acpd-11-121-2011, 2011. Carpenter, L J., Jones, C E., Dunk, R M., Hornsby, K E., and Woeltjen, J.: Air-sea fluxes of biogenic bromine from the tropical and North Atlantic Ocean, Atmos. Chem. Phys., 9, 1805–1816, http://dx.doi.org/10.5194/acp-10-4611-2010doi:10.5194/acp-10-4611-2010, 2009. Dessler, A E.: The effect of deep, tropical convection on the tropical tropopause layer, J. Geophys. Res., 107(D3), 4033, http://dx.doi.org/10.1029/2001JD000511doi:10.1029/2001JD000511, 2002. Dessler, A E., Hanisco, T F., and Fueglistaler, S.: Effects of convective ice lofting on H2O and HDO in the tropical tropopause layer, J. Geophys. Res., 112, D18309, http://dx.doi.org/10.1029/2007JD008609doi:10.1029/2007JD008609, 2007. Dorf, M., Butler, J H., Butz, A., Camy-Peyret, C., Chipperfield, M P., Kritten, L., Montzka, S A., Simmes, B., Weidner, F., and Pfeilsticker, K.: Long-term observations of stratospheric bromine reveal slow down in growth, Geophys. Res. Lett., 33, L24803, http://dx.doi.org/10.1029/2006gl027714doi:10.1029/2006gl027714, 2006. Dvortsov, V L., Geller, M A., Solomon, S., Schauffler, S M., Atlas, E L., and Blake, D R.: Rethinking reactive halogen budgets in the midlatitude lower stratosphere, Geophys. Res. Lett., 26, 1699–1702, 1999. ECMWF: Integrated forecast system CY33r1 Documentation, Part IV: Physical Processes, chap. 5: Convection, p 69, http://www.ecmwf.int/research/ifsdocs/CY33r1/index.html, 2008. Folkins, I., Bernath, P., Boone, C., Lesins, G., Livesey, N., Thompson, A M., Walker, K., and Witte, J C.: Seasonal cycles of O-3, CO, and convective outflow at the tropical tropopause, Geophys. Res. Lett., 33, L16802, http://dx.doi.org/10.1029/2006GL026602doi:10.1029/2006GL026602, 2006. Fueglistaler, S., Wernli, H., and Peter, T.: Tropical troposphere-to-stratosphere transport inferred from trajectory calculations, J. Geophys. Res., 109, D03108, http://dx.doi.org/10.1029/2003JD004069doi:10.1029/2003JD004069, 2004. Fueglistaler, S., Dessler, A E., Dunkerton, T J., Folkins, I., Fu, Q., and Mote, P W.: Tropical Tropopause Layer, Rev. Geophys., 47, RG1004, http://dx.doi.org/10.1029/2008rg000267doi:10.1029/2008rg000267, 2009. Gettelman, A., Lauritzen, P H., Park, M., and Kay, J E.: Processes regulating short-lived species in the tropical tropopause layer, J. Geophys. Res., 114, D13303, http://dx.doi.org/10.1029/2009jd011785doi:10.1029/2009jd011785, 2009. Hendrick, F., Van~Roozendael, M., Chipperfield, M P., Dorf, M., Goutail, F., Yang, X., Fayt, C., Hermans, C., Pfeilsticker, K., Pommereau, J P., Pyle, J A., Theys, N., and De~Maziére, M.: Retrieval of stratospheric and tropospheric BrO profiles and columns using ground-based zenith-sky DOAS observations at Harestua, 60 degrees N, Atmos. Chem. Phys., 7, 18, 4869–4885, http://dx.doi.org/10.5194/acp-7-4869-2007doi:10.5194/acp-7-4869-2007, 2007. Hoskins, B J.: Towards a PV-Theta view of the general-circulation, Tellus, 43, 4, 27–35, 1991. Hossaini, R., Chipperfield, M P., Monge-Sanz, B M., Richards, N. A D., Atlas, E., and Blake, D R.: Bromoform and dibromomethane in the tropics: a 3-D model study of chemistry and transport, Atmos. Chem. Phys., 10, 2, 719–735, http://dx.doi.org/10.5194/acp-10-719-2010doi:10.5194/acp-10-719-2010, 2010. James, R., Bonazzola, M., Legras, B., Surbled, K., and Fueglistaler, S.: Water vapor transport and dehydration above convective outflow during Asian monsoon, Geophys. Res. Lett., 35, L20810, http://dx.doi.org/10.1029/2008GL035441doi:10.1029/2008GL035441, 2008. Kerkweg, A., Jöckel, P., Warwick, N., Gebhardt, S., Brenninkmeijer, C. A M., and Lelieveld, J.: Consistent simulation of bromine chemistry from the marine boundary layer to the stratosphere - Part 2: Bromocarbons, Atmos. Chem. Phys., 8, 19, 5919–5939, http://dx.doi.org/10.5194/acp-8-5919-2008doi:10.5194/acp-8-5919-2008, 2008. Laube, J C., Engel, A., Bönisch, H.and~Mobius, T., Worton, D R., Sturges, W T., Grunow, K., and Schmidt, U.: Contribution of very short-lived organic substances to stratospheric chlorine and bromine in the tropics – a case study, Atmos. Chem. Phys., 8, 23, 7325–7334, http://dx.doi.org/10.5194/acp-8-7325-2008doi:10.5194/acp-8-7325-2008, 2008. Law, K S. and Sturges, W T.: Halogenated very short-lived substances, chap 2, 572~pp., World Meteorological Organization, Geneva, Switzerland, 2007. Lee, A M., Jones, R L., Kilbane-Dawe, I., and Pyle, J A.: Diagnosing ozone loss in the extratropical lower stratosphere, J. Geophys. Res., 107, D11, 4110, http://dx.doi.org/10.1029/2001JD000538doi:10.1029/2001JD000538, 2002. Liang, Q., Stolarski, R S., Kawa, S R., Nielsen, J E., Douglass, A R., Rodriguez, J M., Blake, D R., Atlas, E L., and Ott, L E.: Finding the missing stratospheric Br-y: a global modeling study of CHBr3 and CH2Br2, Atmos. Chem. Phys., 10, 5, 2269–2286, http://dx.doi.org/10.5194/acp-10-2269-2010doi:10.5194/acp-10-2269-2010, 2010. Livesey, N J., Kovalenko, L J., Salawitch, R J., MacKenzie, I A., Chipperfield, M P., Read, W G., Jarnot, R F., and Waters, J W.: EOS Microwave Limb Sounder observations of upper stratospheric BrO: Implications for total bromine, Geophys. Res. Lett., 33, L20817, http://dx.doi.org/10.1029/2006gl026930doi:10.1029/2006gl026930, 2006. Montzka, S A., Butler, J H., Hall, B D., Mondeel, D J., and Elkins, J W.: A decline in tropospheric organic bromine, Geophys. Res. Lett., 30, 15, 1826, http://dx.doi.org/10.1029/2003gl017745doi:10.1029/2003gl017745, 2003. Romps, D M. and Kuang, Z M.: Do Undiluted Convective Plumes Exist in the Upper Tropical Troposphere?, J. Atmos. Sci., 67(2), 468–484, http://dx.doi.org/10.1175/2009jas3184.1doi:10.1175/2009jas3184.1, 2010. Salawitch, R J., Weisenstein, D K., Kovalenko, L J., Sioris, C E., Wennberg, P O., Chance, K., Ko, M. K W., and McLinden, C A.: Sensitivity of ozone to bromine in the lower stratosphere, Geophys. Res. Lett., 32, L05811, http://dx.doi.org/10.1029/2004GL021504doi:10.1029/2004GL021504, 2005. Schofield, R., Kreher, K., Connor, B J., Johnston, P., Thomas, A., Shooter, D., Chipperfield, M., Rodgers, C D., and Mount, G.: Retrieved tropospheric and stratospheric BrO columns over Lauder, New Zealand, J. Geophys. Res., 109, D14304, http://dx.doi.org/10.1029/2003JD004463doi:10.1029/2003JD004463, 2004. Schofield, R., Johnston, P V., Thomas, A., Kreher, K., Connor, B J., Wood, S., Shooter, D., Chipperfield, M P., Richter, A., von Glasow, R., and Rodgers, C D.: Tropospheric and stratospheric BrO columns over Arrival Heights, Antarctica, 2002, J. Geophys. Res., 111, D22310, http://dx.doi.org/10.1029/2005JD007022doi:10.1029/2005JD007022, 2006. Simmons, A J., Uppala, S., Dee, D., and Kobayashi, S.: ERA Interim: New ECMWF reanalysis products from 1989 onwards, ECMWF Newsl., 110, 25–35, 2007. Sinnhuber, B M. and Folkins, I.: Estimating the contribution of bromoform to stratospheric bromine and its relation to dehydration in the tropical tropopause layer, Atmos. Chem. Phys., 6, 4755–4761, http://dx.doi.org/10.5194/acp-6-4755-2006doi:10.5194/acp-6-4755-2006, 2006. Sinnhuber, B M., Arlander, D W., Bovensmann, H., Burrows, J P., Chipperfield, M P., Enell, C F., Frieß, U., Hendrick, F., Johnston, P V., Jones, R L., Kreher, K., Mohamed-Tahrin, N., Müller, R., Pfeilsticker, K., Platt, U., Pommereau, J, P., Pundt, I., Richter, A., South, A., T$\o$rnkvist, K K., Van~Roozendael, M., Wagner, T., and Wittrock, F.: Comparison of measurements and model calculations of stratospheric bromine monoxide, J. Geophys. Res., 107(D19), 4398, http://dx.doi.org/10.1029/2001JD000940doi:10.1029/2001JD000940, 2002. Sinnhuber, B M., Rozanov, A., Sheode, N., Afe, O T., Richter, A., Sinnhuber, M., Wittrock, F., Burrows, J P., Stiller, G P., von Clarmann, T., and Linden, A.: Global observations of stratospheric bromine monoxide from SCIAMACHY, Geophys. Res. Lett., 32, L20810, http://dx.doi.org/10.1029/2005GL023839doi:10.1029/2005GL023839, 2005. Sioris, C E., Kovalenko, L J., McLinden, C A., Salawitch, R J., Van~Roozendael, M., Goutail, F., Dorf, M., Pfeilsticker, K., Chance, K., von Savigny, C., Liu, X., Kurosu, T P., Pommereau, J P., Bosch, H., and Frerick, J.: Latitudinal and vertical distribution of bromine monoxide in the lower stratosphere from Scanning Imaging Absorption Spectrometer for Atmospheric Chartography limb scattering measurements, J. Geophys. Res., 111, D14301, http://dx.doi.org/10.1029/2005jd006479doi:10.1029/2005jd006479, 2006. Theys, N., Van~Roozendael, M., Errera, Q., Hendrick, F., Daerden, F., Chabrillat, S., Dorf, M., Pfeilsticker, K., Rozanov, A., Lotz, W., Burrows, J P., Lambert, J C., Goutail, F., Roscoe, H K., and De~Maziére, M.: A global stratospheric bromine monoxide climatology based on the BASCOE chemical transport model, Atmos. Chem. Phys., 9(3), 831–848, http://dx.doi.org/10.5194/acp-9-831-2009doi:10.5194/acp-9-831-2009, 2009. Tost, H., Lawrence, M G., Brühl, C., Jöckel, P., Team, G., and Team, S.-O.-D A.: Uncertainties in atmospheric chemistry modelling due to convection parameterisations and subsequent scavenging, Atmos. Chem. Phys., 10, 4, 1931–1951, http://dx.doi.org/10.5194/acp-10-1931-2010doi:10.5194/acp-10-1931-2010, 2010. von Glasow, R., von Kuhlmann, R., Lawrence, M G., Platt, U., and Crutzen, P J.: Impact of reactive bromine chemistry in the troposphere, Atmos. Chem. Phys., 4, 2481–2497, http://dx.doi.org/10.5194/acp-4-2481-2004doi:10.5194/acp-4-2481-2004, 2004. Warwick, N J., Pyle, J A., Carver, G D., Yang, X., Savage, N H., O'Connor, F M., and Cox, R A.: Global modeling of biogenic bromocarbons, J. Geophys. Res., 111, D24305, http://dx.doi.org/10.1029/2006jd007264doi:10.1029/2006jd007264, 2006. WMO: Scientific assessment of ozone depletion, 2006 : report of the Montreal Protocol Scientific Assessment Panel, Tech. rep., WMO Global Ozone Research and Monitoring Project – Report No 50, 2006. Wofsy, S C., McElroy, M B., and Yung, Y L.: The Chemistry of Atmospheric Bromine, Geophys. Res. Lett., 2, 215–218, 1975. Wohltmann, I. and Rex, M.: Improvement of vertical and residual velocities in pressure or hybrid sigma-pressure coordinates in analysis data in the stratosphere, Atmos. Chem. Phys., 8, 2, 265–272, http://dx.doi.org/10.5194/acp-8-265-2008doi:10.5194/acp-8-265-2008, 2008. Yang, X., Cox, R A., Warwick, N J., Pyle, J A., Carver, G D., O'Connor, F M., and Savage, N H.: Tropospheric bromine chemistry and its impacts on ozone: A model study, J. Geophys. Res., 110, D23311, http://dx.doi.org/10.1029/2005jd006244doi:10.1029/2005jd006244, 2005. Yokouchi, Y., Hasebe, F., Fujiwara, M., Takashima, H., Shiotani, M., Nishi, N., Kanaya, Y., Hashimoto, S., Fraser, P., Toom-Sauntry, D., Mukai, H., and Nojiri, Y.: Correlations and emission ratios among bromoform, dibromochloromethane, and dibromomethane in the atmosphere, J. Geophys. Res., 110, D23309, http://dx.doi.org/10.1029/2005jd006303doi:10.1029/2005jd006303, 2005.