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- Yurganov, L.N., et al.
(författare)
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A Quantitative Assessment of the 1998 Carbon Monoxide Emission Anomaly in the Northern Hemisphere Based on Total Column and Surface Concentration Measurements
- 2004
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Ingår i: Journal of Geophysical Research. - 0148-0227 .- 2156-2202. ; 109:15, s. D15305-
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Tidskriftsartikel (refereegranskat)abstract
- Carbon monoxide abundances in the atmosphere have been measured between January 1996 and December 2001 in the high Northern Hemisphere (HNH) (30degrees-90degreesN) using two different approaches: total column amounts of CO retrieved from infrared solar spectra and CO mixing ratios measured in situ at ground-based stations. The data were averaged, and anomalies of the CO HNH burden ( deviations of the total tropospheric mass between 30degreesN and 90degreesN from the mean seasonal profile, determined as the 5 year average) were analyzed. The anomalies obtained from in situ and total column data agree well and both show two maxima, by far the largest in October 1998 and a lower one in August 1996. A noticeable decrease of the positive 1998 summer anomaly with increasing height was found. A box model was applied, and anomalies in source rates were obtained under the assumption of insignificant interannual sink variations. In August 1998 the HNH emission anomaly was estimated to be 38 Tg month(-1). The annual 1998 emission positive anomaly was 96 Tg yr(-1). Nearly all excess CO may be attributed to the emissions from boreal forest fires. According to available inventories, biomass burning emits around 52 Tg yr(-1) during the "normal'' years; therefore total biomass emissions in 1998 were as large as 148 Tg yr(-1). In August 1998, CO contribution from the biomass burning was twice as large as that from fossil fuel combustion. The results were compared to available emission inventories.
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| 2. |
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| 3. |
- Meier, Arndt, et al.
(författare)
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Spectroscopic Atlas of Atmoshperic Microwindows in the Middle Infra-Red
- 2004
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Bok (övrigt vetenskapligt/konstnärligt)abstract
- This second edition of the infrared microwindow atlas contains a collection of spectral mi- crowindows commonly used or recently suggested for ground-based, high resolution, infrared solar absoption spectroscopy. These solar observations are aimed at quantifying the abun- dance of trace species in the terrestrial atmosphere. A microwindow is a narrow spectral interval that allows to observe a specific atmospheric absorber unambiguously. The width of a microwindow may vary but is typically between 0.1 and 5cm−1 wide, though wider windows may in some cases be used or multiple narrow windows may be combined in any particular retrieval. The spectra and corresponding simulations shown in the figures are representing solar absorption spectra recorded in Arctic Scandinavia on 15/Mar/1997 (500 to 4370cm −1 ) and 01/Apr/1998 (3950 to 9000cm−1 ). The printed atlas discusses close to 250 microwindows. Lively discussions at the annual meetings of the infrared working group of the Network for Detection of Stratospheric Change (NDSC) have demonstrated a continued high interest in an up-to-date reference work on commonly used microwindows in the field of infrared ground- based remote sensing. The present work attempts to summarise the collective knowledge that the NDSC community has on this topic. The work of many past and present experts in the field have contributed to this compilation and the authors wish to express their thanks to all of them. At present, no recommendations on the optimum selection of microwindows for individual species are provided. That task is beyond the scope of the present work and also depends on the observation site and instrumental parameters. However, where inconsistencies be- tween observation and simulations are striking, or in cases where common pitfalls have been reported, we provide comments to highlight potential problems. Several microwindows have been noted previously in the literature, and we have included a list of references citing their use. We are aware that the current edition is still incomplete, and we encourage our readers to help us fill in the gaps, extend, and improve the atlas.
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