Currently I am a PhD student at the Institute of Environmental Physics at the University of Bremen, more specifically in the DOAS-group. My dissertation has the working title “Observation of Megacity Pollution from Space” and is supervised by Prof. Dr. John P. Burrows. A large part of my PhD work has been financed by the Earth System Science Research School (ESSReS) of the Helmholtz Association.

Research project

One of the largest changes over the last century is the massive increase in human population globally. At the same time, the percentage of people living in large cities is increasing rapidly. These cities account for a large fraction of the total anthropogenic emissions to the atmosphere, and this trend is expected to continue as more and more countries industrialise while population is still on the rise. As a result, large cities are hotspots of pollution problems and at the same time have a significant impact on air quality on a global scale. One particular problem is the formation of ozone, a secondary pollutant with health and climate implications.

Using measurements from satellite based spectrometers, the spatial distribution and the temporal evolution of nitrogen dioxide (|NO2|) and formaldehyde (HCHO), two important ozone precursors, can be determined. These measurements can be applied to validate results of chemistry transport models such as MOZART and also combined with these to assess the impact of pollution from large cities on the atmosphere and to estimate future developments.

In this PhD project, data from the GOME, SCIAMACHY and GOME-2 satellite instruments will be used to derive a consistent dataset of tropospheric columns of |NO2| and HCHO, to study their evolution and the importance of large cities on their global budgets. The work will be performed in close collaboration with the European project megaCITY – Zoom for the Environment (CityZen), an international project on the impact of megacities.



  • Hilboll, A., Richter, A., Rozanov, A., Hodnebrog, Ø., Heckel, A., Solberg, S., Stordal, F. and Burrows, J. P.: Retrieval of tropospheric NO2 columns from SCIAMACHY combining measurements from limb and nadir geometries, Atmos. Meas. Tech. Discuss., 5(4), 5043–5105, doi:10.5194/amtd-5-5043-2012, 2012.
  • Hodnebrog, Ø., Solberg, S., Stordal, F., Svendby, T. M., Simpson, D., Gauss, M., Hilboll, A., Pfister, G. G., Turquety, S., Richter, A., Burrows, J. P., et al.: A model study of the Eastern Mediterranean ozone levels during the hot summer of 2007, Atmos. Chem. Phys. Discuss., 12(3), 7617–7675, doi:10.5194/acpd-12-7617-2012, 2012.


  • Kanakidou, M., Mihalopoulos, N., Kindap, T., Im, U., Vrekoussis, M., Gerasopoulos, E., Dermitzaki, E., Unal, A., Koçak, M., Markakis, K., Melas, D., et al.: Megacities as hot spots of air pollution in the East Mediterranean, Atmos. Environ., 45(6), 1223–1235, doi:10.1016/j.atmosenv.2010.11.048, 2011.
  • Kim, S.-W., McKeen, S. A., Frost, G. J., Lee, S.-H., Trainer, M. K., Richter, A., Angevine, W. M., Atlas, E., Bianco, L., Boersma, K. F., Brioude, J., et al.: Evaluations of NOx and highly reactive VOC emission inventories in Texas and their implications for ozone plume simulations during the Texas Air Quality Study 2006, Atmos. Chem. Phys., 11(22), 11361–11386, doi:10.5194/acp-11-11361-2011, 2011.
  • Noguchi, K., Richter, A., Bovensmann, H., Hilboll, A., Burrows, J. P., Irie, H., Hayashida, S. and Morino, Y.: A feasibility study for the detection of the diurnal variation of tropospheric NO2 over Tokyo from a geostationary orbit, Adv. Space Res., 48, 1551–1564, doi:10.1016/j.asr.2011.06.029, 2011.
  • Richter, A., Begoin, M., Hilboll, A. and Burrows, J. P.: An improved NO2 retrieval for the GOME-2 satellite instrument, Atmos. Meas. Tech., 4, 1147–1159, doi:10.5194/amt-4-1147-2011, 2011.


  • Konovalov, I. B., Beekmann, M., Richter, A., Burrows, J. P. and Hilboll, A.: Multi-annual changes of NOx emissions in megacity regions: nonlinear trend analysis of satellite measurement based estimates, Atmos. Chem. Phys., 10(17), 8481–8498, doi:10.5194/acp-10-8481-2010, 2010.

selected Presentations

  • Hilboll A, Richter A, Burrows JP: NO2 pollution trends in megacities 1996-2010: a multi-satellite approach. ACCENT-Plus Symposium, Urbino, Italy, September 2011.
  • Hilboll A, Richter A, Colette A, Burrows JP: Assessment of decadal trends in tropospheric nitrogen dioxide over large European agglomorations by combining satellite measurements and model data. EGU General Assembly, Vienna, Austria, April 2011.
  • Hilboll A, Richter A, Vrekoussis M, Burrows JP, Gerasopoulos E, Zerefos C, Kindap T, Im U, Mihalopoulos N, Kanakidou M, Trends in tropospheric nitrogen dioxide (NO2) over megacities and large conurbations in the mediterranean and middle east from GOME and SCIAMACHY. 11th IGAC Science Conference, Halifax, Canada, July 2010. [PDF]
  • Hilboll A, Richter A, Vrekoussis M, Burrows JP: Trends in tropospheric NO2 over megacities in the Mediterranean and Middle East regions from GOME and SCIAMACHY. EGU general assembly, Vienna, Austria, May 2010. [PDF]
  • Hilboll A, Trends in tropospheric nitrogen dioxide (NO2) over megacities in the Mediterranean and Middle East regions from GOME and SCIAMACHY. Seminar Ocean, Ice, and Atmosphere, Institute of Environmental Physics, University of Bremen, Bremen, Germany, April 2010. [PDF]
  • Hilboll A:
    Satellite measurements of tropospheric trace gases in the CHARMEX project.
    CHARMEX WP1 Trends workshop, Paris, France, October
    1. [PDF]
  • Richter A, Hilboll A, Burrows JP: Improvements in GOME-2 retrievals of NO2. O3M SAF User & Algorithm Forum, Halkidiki, Greece, June 2009.
  • Hilboll A: Projekt “atmosfair” – eine Antwort auf die Klimafolgen des Flugreisens? International summer school “Prima Klima! Auswirkungen des Klimawandels auf Freizeit und Tourismus”, Hochschule Bremen, Germany, July 2008.

selected Posters

  • Hilboll A, Richter A, Rozanov A, Heckel A, Burrows JP: Tropospheric NO2 from SCIAMACHY limb/nadir matching. 5th International DOAS Workshop, Mainz, Germany, July 2011. Hilboll A, Richter A, and Burrows JP:
  • Intercomparison of different stratospheric correction schemes for the retrieval of tropospheric nitrogen dioxide columns from satellite. 38th COSPAR Scientific Assembly, Bremen, Germany, July 2010. [PDF]
  • Hilboll A, Leitão J, Vrekoussis M, Richter A and Burrows JP:
    Trends in tropospheric NO2 from SCIAMACHY over megacities in the Mediterranean and Middle East.
    ESA Atmospheric Science Conference, Barcelona, Spain, September
    1. [PDF]
  • Hilboll A: Observation of Megacity pollution from space. 1st ESSReS annual retreat, Bremerhaven, Germany, August 2009. [PDF]
  • Hilboll A, Wieters N, Richter A, Sinnhuber BM, Burrows JP: The impact of the stratospheric correction on tropospheric NO2 measurements from satellites. EGU General Assembly, Vienna, Austria, April 2009. [PDF]

Curriculum Vitae

A PDF version of my CV is available here.

other Activities



  • A0 poster template for Scribus: For my poster at EGU 2009 I created a template in [Scribus, which can be downloaded here. It is in A0 landscape (!) format.