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| Titel |
Nördlinger Ries campaign on Soil Emissions (NORISE) - DOAS measurements of NO2 and HCHO in an agricultural region |
| VerfasserIn |
Jan Zörner, Julia Remmers, Steffen Dörner, Yang Wang, Philipp Eger, Dennis Pöhler, Thomas Behrendt, Franz Meixner, Marloes Penning de Vries, Thomas Wagner |
| Konferenz |
EGU General Assembly 2016
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250132003
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| Publikation (Nr.) |
 EGU/EGU2016-12465.pdf |
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| Zusammenfassung |
| Soil is a major source of total nitrogen oxide (NOx = NO + NO2) emissions with a
fraction of about 15% on a global basis. Soil emissions, stemming from bacterial
emissions of NO, are controlled by abiotic and microbiological processes which
themselves depend on ambient environmental conditions like soil type, moisture content,
temperature as well as agricultural management practices such as fertilization. In
recent laboratory experiments it was found that dry soils also exhibit enhanced
emissions of several volatile organic compounds (VOC) including HCHO when first
wetted.
At present, studies on soil emissions in humid climates are limited to point samples and
laboratory measurements. Thus, a campaign was organized that is dedicated to the
analysis of trace gases which are potentially emitted from soils over an entire area
using ground based mini-MAX-DOAS measurements. Since soil emissions are
assumed to be highest from lands predominantly used for agriculture, the Nördlinger
Ries in Bavaria, Germany, a 25 km wide circular plain formed by a meteor impact
about 14.5 million years ago, was chosen which nowadays is dominated by arable
land.
The main objective of the NORISE campaign was to characterize trace gas levels in a
highly agricultural environment. The time frame, consequently, covered a whole growing
season from April 2014 to January 2015. The focus was on trace gases which can
be measured using the DOAS approach in the UV/VIS spectral range, i.e. NO2
and HCHO, using two mini-MAX-DOAS instruments and one long-path DOAS
instrument.
The retrieved NO2 and HCHO column densities were examined for long-term variations
over the entire growing season and short-term events which are both linked to environmental
conditions like precipitation patterns and temperature changes. In addition, the analysis of
soil samples taken from fields, distinguished between organic and conventional cultivation,
gives further insights into soil activities.
In this work, we present updated results on data comparisons for the three DOAS-type
instruments with special focus on data which is filtered for specific wind directions as well as
cloud conditions. Furthermore, to evaluate the sources of NO2 and HCHO, their height
distribution are studied in detail based on profile inversions. |
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