Spectroscopic Measurements of Tropospheric HCN and C2H6 Over Addis Ababa

Alemu, Ambachew Abeje (2011) Spectroscopic Measurements of Tropospheric HCN and C2H6 Over Addis Ababa. Masters thesis, Addis Ababa University.

[img] PDF (Spectroscopic Measurements of Tropospheric HCN and C2H6 over Addis Ababa)
Ambachew, Abeje.pdf - Accepted Version
Restricted to Repository staff only

Download (19MB) | Request a copy


The atmospheric concentrations of HCN and C2H6 are important indicators of tropospheric pollution and transport because they are primarily emitted from biomass burning and anthropogenic sources. Tropospheric column amounts and mixing ratios of C2H6 and HCN were retrieved from ground-based infrared solar spectra using a vertical profile retrieval algorithm (PROFFIT). The spectra were recorded with high spectral resolution Fourier transform infrared (FTIR) spectrometer at Addis Ababa (9.010 N, 38.760 E and 2.45 km asl), Ethiopia from May 2009 to February 2011. The selected microwindows are found to be good with a maximum residual error of less than 0.1% for HCN and less than 3.5% for C2H6 retrievals. We found that the degrees of freedom for HCN is 2 and 1.5 for C2H6 with a total statistical error 38.78% and 17.74% and a total systematic error 37.33% and 12.04% respectively. HCN is more sensitive in the upper atmosphere while C2H6 is sensitive in the lower atmosphere. The total column amount of HCN ranges from 9.83×1018 to 6.39×1019 while of C2H6 from 3.60×1019 to 1.70×1020 molecules/m2. The maximum volume mixing ratio for both gases was found in March.

Item Type: Thesis (Masters)
Subjects: G Geography. Anthropology. Recreation > GE Environmental Sciences
Q Science > Q Science (General)
Q Science > QC Physics
Q Science > QD Chemistry
Divisions: Africana
Depositing User: Selom Ghislain
Date Deposited: 26 Jun 2018 13:13
Last Modified: 26 Jun 2018 13:13
URI: http://thesisbank.jhia.ac.ke/id/eprint/4729

Actions (login required)

View Item View Item