The current focus of my research is investigating the impact of urban form and vegetation on air pollution (nitrogen dioxide, ozone and particulate matter). The principal tools for this work are the CiTTyCAT box model which I have adapted to simulate chemistry and deposition in urban street canyons, and the WRF/Chem atmospheric chemistry transport model.

This work is carried out as part of the Urban Futures project. This project brings together researchers from a myriad of disciplines (e.g. architecture, engineering, ecology, social sciences) to address the problems of ensuring that those actions taken in the name of sustainability now will still continue to work into the future. For more detail on the group's work visit www.urban-futures.org.

During my PhD I investigated chemistry in the boundary layer above a tropical rainforest in Borneo, as part of the OP3 project (www.es.lancs.ac.uk/op3). My particular focus was the emission and chemistry of biogenic volatile organic compounds (BVOCs), of which isoprene was the most abundant. I used the MEGAN model to simulate emission of these compounds and the CiTTyCAT box model to probe the chemistry. A central problem addressed was the oxidation of isoprene by OH, including OH recycling and segregation processes. I also used a one-dimensional model to investigate night-time NOx and ozone chemistry, and box model studies to investigate the effect of land-use change from tropical rainforest to oil palm plantation. I retain interests in these areas.

A large portion of my research has utilised the CiTTyCAT box/trajectory model. A community version of CiTTyCAT is being developed in collaboration with partners at Reading and Cambridge, and is held on a Subversion controlled repository at Lancaster. The model includes single box, two-box, trajectory and trajectory-ensemble modes. Detailed organic chemistry for isoprene and monoterpenes has been included, with on-line emissions from the MEGAN model. If you'd like to make use of the model for your research please contact me for a copy of the code.

Pugh, T., Ryder, J., MacKenzie, A., Moller, S., Lee, J., Helfter, C., Nemitz, E., Lowe, D., and Hewitt, C.: Modelling chemistry in the nocturnal boundary layer above tropical rainforest and a generalised effective nocturnal ozone deposition velocity for sub-ppbv NOx conditions, Journal of Atmospheric Chemistry, 65, 89-110, doi:10.1007/s10874-011-9183-4, 2010.

Pugh, T. A. M., MacKenzie, A. R., Langford, B., Nemitz, E., Misztal, P. K., and Hewitt, C. N.: The influence of small-scale variations in isoprene concentrations on atmospheric chemistry over a tropical rainforest, Atmos. Chem. Phys., 11, 4121-4134, doi:10.5194/acp-11-4121-2011, , http://www.atmos-chem-phys.net/11/4121/2011/acp-11-4121-2011.html, 2011.

Langford, B., Misztal, P. K., Nemitz, E., Davison, B., Helfter, C., Pugh, T. A. M., MacKenzie, A. R., Lim, S. F., and Hewitt, C. N.: Fluxes and concentrations of volatile organic compounds from a South-East Asian tropical rainforest, Atmospheric Chemistry and Physics, 10, 8391-8412, doi:10.5194/acp-10-8391-2010, http://www.atmos-chem-phys.net/10/8391/2010/, 2010.

Pugh, T. A. M., MacKenzie, A. R., Hewitt, C. N., Langford, B., Edwards, P. M., Furneaux, K. L., Heard, D. E., Hopkins, J. R., Jones, C. E., Karunaharan, A., Lee, J., Mills, G., Misztal, P., Moller, S., Monks, P. S., and Whalley, L. K.: Simulating atmospheric composition over a South-East Asian tropical rainforest: performance of a chemistry box model, Atmospheric Chemistry and Physics, 10, 279-298, doi:10.5194/ acp-10-279-2010, http://www.atmos-chem-phys.net/10/279/2010/, 2010.

Hewitt, C. N., Lee, J. D., MacKenzie, A. R., Barkley, M. P., Carslaw, N., Carver, G. D., Chappell, N. A., Coe, H., Collier, C., Commane, R., Davies, F., Davison, B., DiCarlo, P., Di Marco, C. F., Dorsey, J. R., Edwards, P. M., Evans, M. J., Fowler, D., Furneaux, K. L., Gallagher, M., Guenther, A., Heard, D. E., Helfter, C., Hopkins, J., Ingham, T., Irwin, M., Jones, C., Karunaharan, A., Langford, B., Lewis, A. C., Lim, S. F., MacDonald, S. M., Mahajan, A. S., Malpass, S., McFiggans, G., Mills, G., Misztal, P., Moller, S., Monks, P. S., Nemitz, E., Nicolas-Perea, V., Oetjen, H., Oram, D. E., Palmer, P. I., Phillips, G. J., Pike, R., Plane, J. M. C., Pugh, T., Pyle, J. A., Reeves, C. E., Robinson, N. H., Stewart, D., Stone, D., Whalley, L. K., and Yin, X.: Overview: oxidant and particle photochemical processes above a south-east Asian tropical rainforest (the OP3 project): introduction, rationale, location characteristics and tools, Atmos. Chem. Phys., 10, 169-199, http://www.atmos-chem-phys.net/10/169/2010/, 2010.

Hewitt, C. N., MacKenzie, A. R., Di Carlo, P., Di Marco, C. F., Dorsey, J. R., Evans, M., Fowler, D., Gallagher, M. W., Hopkins, J. R., Jones, C. E., Langford, B., Lee, J. D., Lewis, A. C., Lim, S. F., McQuaid, J., Misztal, P., Moller, S. J., Monks, P. S., Nemitz, E., Oram, D. E., Owen, S. M., Phillips, G. J., Pugh, T. A. M., Pyle,J. A., Reeves, C. E., Ryder, J., Siong, J., Skiba, U., and Stewart, D. J.: Nitrogen management is essential to prevent tropical oil palm plantations from causing ground-level ozone pollution, Proc. Nat. Acad. Sci. U.S.A., 106, 18 447 - 18 451, doi:10.1073/pnas.0907541106, 2009.

I also have some (amateur!) interest in weather forecasting, and occasionally run WRF weather forecasts for Lancaster. See http://lec-cirrus.lancs.ac.uk for Lancaster weather related information. These pages are maintained by Andy Horseman.

I put this phrasebook together for a canoeing trip to Malawi. It's only a few bits and pieces, and if you look at it you'll realise it's heavily weighted towards the things canoeists and campers might want, but I'm making it available as there's such a dearth of Chichewa material available on the web. It has been checked over for correctness by a local, but I apologise in advance for any mistakes it may contain!