Publications of G. Helas
All genres
Journal Article (38)
21.
Journal Article
Rausch, A., , , and Helas, G.: Complex refractive index of aerosols during LACE 98 as derived from the analysis of individual particles, Journal of Geophysical Research, 107(D21), doi:10.1029/2000JD000195, 2002.
, , 22.
Journal Article
Formenti, P., , , , , Helas, G. and Andreae, M. O.: Aerosol optical depth over a remote semi-arid region of South Africa from spectral measurements of the daytime solar extinction and the nighttime stellar extinction, Atmospheric Research, 62(1-2), 11–32 [online] Available from: http://hdl.handle.net/11858/00-001M-0000-0014-9108-E, 2002.
23.
Journal Article
Rausch, A., , , and Helas, G.: The complex refractive index of aerosols during LACE 98 as derived from the analysis of indivi-dual particles, Journal of Aerosol Science, 32, (Suppl), 683–684 [online] Available from: http://hdl.handle.net/11858/00-001M-0000-0014-93DE-D, 2001.
, , 24.
Journal Article
Helas, G., and : Characterization and transport of aerosols over equatorial eastern Africa, Global Biogeochemical Cycles, 15, 633–672 [online] Available from: http://hdl.handle.net/11858/00-001M-0000-0014-9286-C, 2001.
, , , 25.
Journal Article
Marufu, L., , , , Andreae, M. O. and Helas, G.: Biofuel consumption rates and patterns in Kenya, Biomass and Bioenergy, 20, 83–99 [online] Available from: http://hdl.handle.net/11858/00-001M-0000-0014-9224-6, 2001.
, 26.
Journal Article
Marufu, L., , , Andreae, M. O. and Helas, G.: Biofuel availability and domestic use patterns in Kenya, Biomass and Bioenergy, 20, 71–82 [online] Available from: http://hdl.handle.net/11858/00-001M-0000-0014-9222-A, 2001.
, 27.
Journal Article
Marufu, L., , , Andreae, M. O. and Helas, G.: Carbon monoxide and nitric oxide from biofuel fires in Kenya, Energy Conversion and Management, 42, 1517–1542 [online] Available from: http://hdl.handle.net/11858/00-001M-0000-0014-9226-2, 2001.
, 28.
Journal Article
Lange, L., , Helas, G., , , , , , , , , , Lelieveld, J. and Andreae, M. O.: Detection of lightning-produced NO in the midlatitude upper troposphere during STREAM 1998, Journal of Geophysical Research, 106(D21), 27,777–27,786 [online] Available from: http://hdl.handle.net/11858/00-001M-0000-0014-922E-1, 2001.
29.
Journal Article
Rausch, A., , and Helas, G.: Calculation of scattering and absorption of light by irregular shaped and mixed particles, Journal of Aerosol Science, 32, (Suppl), 419–420 [online] Available from: http://hdl.handle.net/11858/00-001M-0000-0014-927C-4, 2001.
30.
Journal Article
Kirkman, G. A., , Andreae, M. O., and Helas, G.: Distribution of aerosols, ozone and carbon monoxide over southern Africa, South African Journal of Science, 96, 423–432 [online] Available from: http://hdl.handle.net/11858/00-001M-0000-0014-9440-7, 2000.
31.
Journal Article
Marufu, L., , Lelieveld, J., Andreae, M. O. and Helas, G.: Photochemistry of the African troposphere: The influence of biomass burning emissions, Journal of Geophysical Research, 105, 14,513–14,530 [online] Available from: http://hdl.handle.net/11858/00-001M-0000-0014-9454-C, 2000.
32.
Journal Article
Fischer, H., , , Helas, G., Hoor, P., Lange, L., Lelieveld, J., Schiller, C. L., , Williams, J. and Wong, S.: Trace gas distribution in the tropopause region: First results from the STREAM-98 summer campaign in Timmins, Canada, Geophysical Research Abstracts, 1 [online] Available from: http://hdl.handle.net/11858/00-001M-0000-0014-97B8-1, 1999.
33.
Journal Article
Helas, G.: A seasonal air transport climatology for Kenya, Journal of Geophysical Research, 104, 14237–14244 [online] Available from: http://hdl.handle.net/11858/00-001M-0000-0014-964A-3, 1999.
, , , and 34.
Journal Article
Rausch, A., , , and Helas, G.: Elemental and phase composition of aerosols sampled during LACE 98, Journal of Aerosol Science, 30S, 517–518 [online] Available from: http://hdl.handle.net/11858/00-001M-0000-0014-96AA-9, 1999.
, 35.
Journal Article
Kettle, A. J., Andreae, M. O., , Andreae, T. W., , , , , , , Helas, G., , , , , , , , , , , , , , Roberts, G., Schebeske, G., , , , and : A global database of sea surface dimethylsulfide (DMS) measurements and a simple model to predict sea surface DMS as a function of latitude, longitude and month, Global Biogeochemical Cycles, 13(2), 399–444 [online] Available from: http://hdl.handle.net/11858/00-001M-0000-0014-9600-7, 1999.
36.
Journal Article
Marufu, L., , Andreae, M. O., Lelieveld, J. and Helas, G.: Spatial and temporal variation in biofuel consumption rates and patterns in Zimbabwe: Implications for atmospheric trace gas emission, Biomass and Bioenergy, 16, 311–332 [online] Available from: http://hdl.handle.net/11858/00-001M-0000-0014-9616-8, 1999.
37.
Journal Article
Rausch, A., , , , and Helas, G.: High-resolution scanning electron microscopy of individual aerosol particles obtained during LACE 98, Journal of Aerosol Science, 30S, 515–516 [online] Available from: http://hdl.handle.net/11858/00-001M-0000-0014-96EE-4, 1999.
38.
Journal Article
Wentzel, M., , Helas, G., , and : Giant dendritic carbonaceous particles in Soweto aerosols, South African Journal of Science, 95, 141–145 [online] Available from: http://hdl.handle.net/11858/00-001M-0000-0014-96DA-E, 1999.
Book Chapter (1)
39.
Book Chapter
Andreae, M. O. and Helas, G.: Biomass burning in Africa: role in atmospheric change and opportunities for emission mitigation, in Climate Change and Africa, edited by , pp. 79–89, Cambridge University Press, New York. [online] Available from: http://hdl.handle.net/11858/00-001M-0000-0014-8B80-B, 2005.
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