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Centre for Atmospheric Science

Dr Paul Connolly

Dr Paul Connolly

Lecturer to Environmental, Earth Scientist and Geology students

BSc (Hons) Pure and Applied Physics (UMIST) 2001, PhD Atmospheric science (Manchester) 2006

Room Number: 3.08 [Simon Building]
Tel: +44 (0)161 306 3921
Email: P.Connolly@manchester.ac.uk


Professional biography

I graduated from UMIST in 2001 gaining a 1st class degree in Pure and Applied Physics, awarded course prize for best performance in all three years.

At the start of 2006 I gained my PhD at UMIST, which investigated the impacts that particulate pollution can have on a tropical cumulo-nimbus (Cb) known as Hector. The work found that there may be optimal amounts of pollution that could increase the frequency of upper level cloudiness in the tropics.I find this interesting as it is related to the area of geoengineering in stratus clouds where we believe that the effect is that increased aerosol concentrations result in more reflective clouds. If m modelling results for tropical cumulo-nimbus clouds are correct then it suggests that if they form in polluted regions the clouds would become less reflective and hence have a warming effect on the planet. This idea is now receiving wider recognition and is now becoming recognised as an important indirect effect of aerosols on clouds. More recently my research has shown that aerosols do indeed significantly affect such strong convection.

Throughout my PhD I took part in numerous field projects, which involved measing high level cirrus outflow in Darwin, Australia; measuring aerosol-cloud interactions on the Jungfraujoch; understanding ice nucleation in a state-of-the-art laboratory facility in Germany; and measuring ice in cumulus clouds from the FAAM BAe-146 research aircraft. In 2004, I visited the National Centre for Atmospheric Research (NCAR) in Boulder, Colorado, which served to strengthen my interests in understanding ice processes in clouds.

In 2006 I took up the position of lecturer in SEAES and am currently teaching earth and environmental scientists problem solving skills (EART10160), statistics and computer data analysis (EART20170), and supervise several third year projects each year (EART30300).I also teach third year physics undergraduates on the Meteorology and Atmospheric Physics module (EART30351). Another role I have recently taken on in the department is admissions officer for Environmental Science, I will be learning what this role entails as time goes by!

Since joining SEAES I have become involved in the construction of a large cylindrical cloud chamber known as  MICC (the Manchester Ice Cloud Chamber). This is situated on three floors of the Simon Building and is currently being used to investigate the formation of airborne snow crystals. We do this by artificially producing a cloud and seeding it with ice crystals. Techniques are being developed to record the growth rates of an ice crystal population with time by vapour deposition, aggregation and riming (accretion of liquid drops onto the ice).  This new and exciting experimental set-up is available for environmental students to use to investigate cloud processes as part of their project work in the third year.We recently published a paper that used the chamber to quantify the aggregation efficiency of ice crystals.

I am also very interested in understanding how efficient certain minerals are at nucleating ice from supercooled water. Contrary to popular belief, ice does not form from pure water once the temperature is colder than 0 C. It requires an energy barrier for crystallisation to be overcome. Infact, in pure water this will not happen until temperatures are colder than -35C. However, certain minerals that are present in the earth's atmosphere can decrease the height of this energy barrier and so can nucleate ice at much warmer temperatures. Understanding how this happens, and how this impacts on precipitation is a key area of interest in my work.

Hobbies of mine include athletics (running), and I regularly take part in cross country, road races and track races. In the autumn and winter I run cross country (and kind of dread it to be honest, but its a kind of painful pleasure), whereas in the late winter and spring I run road races (I usually line up for the Bupa Manchester 10K in May) and after that I concentrate on track running for the rest of the summer. I train at Salford Mets Athletics Club (the running club thats actually in Salford, unlike the other club that call themselves Salford!), which tends towards the middle distances, but occasionally take part in longer distance races. I also enjoy cycling (but not so much around Manchester because of the poor cycle paths and roads!).


Specific research interests

Cloud physics and aerosols, ice nucleation, numerical modelling, microphysics


  • Allen, G., et al., 2008: Aerosol and trace-gas measurements in the darwin area during the wet season. J. Geophys. Res., 113(D06306).
  • Baran, A. J., P. J. Connolly, and C. Lee, 2008: Testing an ensemble model of ice crystals using in situ estimates of ice water content, volume extinction coefficient and ice crystal effective dimension. part i: The midlatitudes. Quart. J. Roy. Meteor. Soc., in review.
  • Baran, A. J., P. J. Connolly, and C. Lee, 2009: Testing an ensemble model of cirrus ice crystals using midlatitude in situ estimates of ice water content, volume extinction coefficient and the total solar optical depth. J. Quant. Spec. and Rad. Transfer., 110, 1579–1598.
  • Buttner, S., M. Schnaiter, R. Wagner, C. Linke, O. Mohler, P. R. Field, and P. J. Connolly, 2004:  Optical characterisation of ice crystals growing at simulated cirrus conditions. 14th ICCP, Bologna, Italy.
  • Choularton, T. W., et al., 2005: Influence of aerosol on precipitation production in mixed phase clouds. IGAC speciality conference on the indirect effects of aerosols, Manchester, UK.
  • Choularton, T. W., et al., 2007: The influence of biomass burning aerosol on deep tropical convection: results from the active campaign. IUGG XXIV general assembly, Perugia, Italy.
  • Choularton, T. W., et al., 2008: The influence of small aerosol particles on the properties of water and ice clouds. Faraday discussions, 137, 205–222.
  • Connolly, P. J., 2005: An investigation into the microphysics of deep convection, Ph.D. thesis, University of Manchester.
  • Connolly, P. J., 2007a: Observations and modelling of the heterogeneous freezing mechanism. IUGG XXIV general assembly, Perugia, Italy.
  • Connolly, P. J., J. Cardwell, M. W. Gallagher, and T. W. Choularton, 2003: Modelling of cirrus outflow from hector during emerald-2. Royal Meteorological Society conference, University of East Anglia, Norwich.
  • Connolly, P. J., T. W. Choularton, M. W. Gallagher, K. N. Bower, M. J. Flynn, and J. Whiteway, 2004a: Observations and modelling of cirrus outflow from hector during the emerald-2 campaign. 14th ICCP, Bologna, Italy.
  • Connolly, P. J., T. W. Choularton, M. W. Gallagher, and J. Whiteway, 2004b: Observations and modelling of the influences of aerosol on the ice phase in hector thunderstorms. 8th International Global Atmospheric Chemistry Conference, Christchurch, New Zealand.
  • Connolly, P. J., P. R. Field, O. Mohler, S. Buttner, H. Saathoff, A. J. Heymsfield, M. W. Gallagher, and T. W. Choularton, 2004c: Simulations of ice crystal nucleation and growth: results from the aida chamber. 14th ICCP, Bologna, Italy.
  • Connolly, P. J., T. W. Choularton, M. W. Gallagher, K. N. Bower, M. J. Flynn, and J. Whiteway,2005a: Formation of precipitation in intense tropical hector thunderstorms. European Geophysical Union, Vienna.
  • Connolly, P. J., T. W. Choularton, M. W. Gallagher, K. N. Bower, and J. Whiteway, 2005b: The role of cloud microphysics on the dynamics of intense hector thunderstorms. Royal Meteorological Society conference, Exeter.
  • Connolly, P. J., O. Mohler, R. J. Cotton, T. W. Choularton, and M. W. Gallagher, 2005c: The role of ice nucleation mode initiated by desert dust on the habit of vapour grown ice crystals. European Geophysical Union, Vienna.
  • Connolly, P. J., O. Mohler, P. R. Field, R. J. Cotton, T. W. Choularton, M. W. Gallagher, and S. Benz, 2005d: Laboratory studies of ice formation mechanisms in mixed phase clouds. Royal Meteorological Society conference, Exeter.
  • Connolly, P. J., C. P. R. Saunders, M. W. Gallagher, K. N. Bower, M. J. Flynn, T. W. Choularton, J. Whiteway, and P. Lawson, 2005e: Aircraft observations of the influence of electric fields on the aggregation of ice crystals. Quart. J. Roy. Meteor. Soc., 131, 1695–1712.
  • Connolly, P. J., O. Mohler, M. W. Gallagher, and T. W. Choularton, 2006a: Measurement and parameterisation of the bimodal heterogeneous ice activation behaviour of desert dusts. 12th conference on Cloud Physics, Madison, WI, USA.
  • Connolly, P. J., G. Vaughan, T. W. Choularton, K. N. Bower, M. W. Gallagher, and M. J. Flynn, 2006b: Modelling and measurements of interactions between aerosols and clouds in an intense tropical thunderstorm during active. International Aerosol Conference, St. Paul Minnesota.
  • Connolly, P. J., T. W. Choularton, M. W. Gallagher, K. N. Bower, M. J. Flynn, and J. Whiteway, 2007a: Cloud resolving simulations of intense tropical, hector thunderstorms: Implications for aerosol cloud interactions. Quart. J. Roy. Meteor. Soc., 132, 3079–3106.
  • Connolly, P. J., M. J. Flynn, Z. Ulanowski, T. Ibbottson, M. W. Gallagher, and T. W. Choularton, 2007b: Calibration of the cloud particle imager probes using calibration beads and ice crystal analogs: The depth-of-field. J. Atmos. Ocean. Technol., 24, 1860–1879.
  • Connolly, P. J., A. J. Heymsfield, and T. W. Choularton, 2007c: Modelling the influence of rimer surface temperature on the glaciation of intense thunderstorms: The rime-splinter mechanism of ice multiplication. Quart. J. Roy. Meteor. Soc., 132, 3059–3077.
  • Connolly, P. J., P. May, G. Vaughan, and G. Allen, 2007d: Influence of aerosols on deep convection. European Geophysical Union abstracts, General Assembly, AGU.
  • Connolly, P. J., C. P. R. Saunders, and M. W. Gallagher, 2008a: The manchester ice cloud chamber (micc): A new cloud-fall chamber for studies of ice cloud microphysics. British Association of Crystal Growth, Loughborough.
  • Connolly, P. J., G. Vaughan, P. May, P. Minnis, K. Ayers, G. Allen, M. Zhu, and T. W. Choularton, 2008b: A study into the effects of aerosols on intense hector thunderstorms in 2005/2006. 15th ICCP, Cancun, Mexico.
  • Connolly, P. J., O. Mohler, P. R. Field, H. Saathoff, R. Burgess, M. W. Gallagher, and T. W. Choularton, 2009: Studies of ice nucleation on three different types of dust particle. Atmos. Chem. Phys., 9, 2805–2824.
  • Connolly, P. J., C. Emersic, and P. R. Field, 2011: A laboratory investigation into the aggregation efficiency of small ice crystals. Atmos. Chem. Phys. Discus., 11, 25,655–25,707.
  • Cozic, J., B. Verheggen, S. Mertes, P. J. Connolly, K. N. Bower, A. Petzold, and U. Baltensperger, 2007: Scavenging of black carbon in mixed phase clouds at the high alpine site jungfraujoch. Atmos. Chem. Phys., 7, 1797–1802.
  • Crawford, I., et al., 2011: Studies of propane flame soot acting as heterogeneous ice nuclei in conjunction with single particle soot photometer measurements. Atmos. Chem. Phys., 11, 9549–9561.
  • Crosier, J., et al., 2011: Observations of ice multiplication in a weakly convective cell embedded in supercooled mid-level stratus. Atmos. Chem. Phys., 11, 257–273.
  • Dearden, C., P. J. Connolly, T. W. Choularton, and P. R. Field, 2011: Evaluating the effects of microphysical complexity in idealised simulations of trade wind cumulus using the factorial method. Atmos. Chem. Phys., 11, 2729–2746.
  • Dickinson, C., L. Komguem, J. A. Whiteway, M. Illnicki, V. Popovici, W. Junkermann, P. J. Connolly, and J. Hacker, 2010: Lidar atmospheric measurements on mars and earth. Planetary and Space Science, available online.
  • Emersic, C., and P. J. Connolly, 2011: The breakup of levitating water drops observed with a high speed camera. Atmos. Chem. Phys. Discus., 2011, 11,739–11,769.
  • Field, P. R., R. J. Cotton, O. Mohler, M. Schnaiter, M. Kramer, P. J. Connolly, and A. J. Heymsfield, 2004: Investigation of the nucleation ability of two desert dust aerosol samples at −50 ◦ C. 14th ICCP, Bologna, Italy.
  • Field, P. R., O. Mohler, P. J. Connolly, M. Kramer, R. J. Cotton, A. J. Heymsfield, H. Saathoff, and M. Schnaiter, 2006: Some ice nucleation characteristics of asian and saharan desert dust. Atmos. Chem. Phys., 6, 2991–3006.
  • Gallagher, M. W., P. J. Connolly, O. Mohler, P. R. Field, R. Burgess, and T. W. Choularton, 2008: Freezing of cloud by mineral particles in the aida chamber. 15th ICCP, Cancun, Mexico.
  • Gallagher, M. W., P. J. Connolly, A. J. Heymsfield, K. N. Bower, T. W. Choularton, G. Allen, M. J. Flynn, G. Vaughan, and J. Hacker, 2011: Observations and modelling of microphysical variability, aggregation and sedimentation in tropical storm cirrus outflow regions. Atmos. Chem. Phys. Discus., 11, 23,761–23,800.
  • Gallagher, M. W., et al., 2005: An overview of the microphysical structure of cirrus clouds observed during emerald-1. Quart. J. Roy. Meteor. Soc., 131, 1143–1169.
  • Huang, Y., et al., 2008: The development of ice in a cumulus cloud over southwest england. New J. Phys., 10, 105,021.
  • Kaye, P. H., E. Hirst, R. S. Greenaway, Z. Ulanowski, E. Hesse, P. J. DeMott, C. P. R. Saunders,  and P. J. Connolly, 2008: Classifying atmospheric ice crystals by spatial light scattering. Opticsletters, 33(13), 1545–1547.
  • May, P., G. Allen, G. Vaughan, and P. J. Connolly, 2009: Aerosol and thermodynamic effects on tropical cloud systems during twp-ice and active. Atmos. Chem. Phys., 9, 15–24.
  • Mertes, S., et al., 2007: Counterflow virtual impactor based collection of small ice particles in mixed-phase clouds for the physico-chemical characterization of tropospheric ice nuclei: Sampler description and first case study. Aerosol Science and Technol, 41, 848–864.
  • Mohler, O., et al., 2004: Formation, growth and habit of ice crystals nucleated on mineral dust aerosol. 14th ICCP, Bologna, Italy.
  • Mohler, O., et al., 2006: Efficiency of the deposition mode ice nucleation on mineral dust particles. Atmos. Chem. Phys., 6, 3007–3021.
  • Saunders, R. W., et al., 2010: An aerosol chamber investigation of the heterogeneous icenucleating potential of refractory nanoparticles. Atmos. Chem. Phys., 10, 1227–1247.
  • Ulanowski, Z., P. J. Connolly, M. J. Flynn, M. W. Gallagher, A. J. M. Clarke, and E. Hesse, 2004: Using ice crystal analogues to validate cloud ice parameter retrievals from the cpi ice spectrometer data. 14th International Conference on Clouds and Precipitation, Bologna, Italy.
  • Verheggen, B., et al., 2007: Aerosol partitioning between the interstitial and the condensed phase in mixed phase clouds. J. Geophys. Res., 112(D23), 23,202–.
  • Whiteway, J., C. Cook, M. W. Gallagher, R. Busen, T. W. Choularton, K. N. Bower, P. J. Connolly,M. J. Flynn, and J. Hacker, 2004a: Anatomy of cirrus clouds. 22nd International laser radar conference (ILRC), Matera Italy.
  • Whiteway, J., et al., 2004b: Anatomy of cirrus clouds: results from the emerald airborne campaigns. Geophys. Res. Lett., 31, 24,102–24,105.
  • Zhu, M., P. J. Connolly, G. Vaughan, T. W. Choularton, and P. May, 2011: Numerical simulation of tropical island thunderstorms (hectors) during the active campaign. Met. Apps., in preparation.

Recent and forthcoming publications

  • Connolly, P. , G. Vaughan , P.T. May , C. Chemel , G. Allen , T. W. Choularton, M. W. Gallagher , K. N. Bower , J. Crosier , C. Dearden, 2011, Can aerosols influence deep tropical convection? Aerosol indirect effects in the Hector island thunderstorm, submitted to Quarterly Journal of the Royal Met Soc.