 |
| Titel |
Methane and Nitrous oxide emissions in The Netherlands: ambient measurements compared to the national inventories |
| VerfasserIn |
S. van der Laan, R. E. M. Neubert, H. A. J. Meijer |
| Konferenz |
EGU General Assembly 2009
|
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 11 (2009) |
| Datensatznummer |
250026601
|
|
|
|
|
|
| Zusammenfassung |
| The partners of the United Nations Framework Convention on Climate Change
(UNFCCC) commit themselves to annually report their greenhouse gas emissions.
These reports are based on inventories (i.e. by counting sources and sinks with
certain estimated emission factors), but the UNFCCC also demands for parties to
develop and implement an independent validation system based on atmospheric
measurements.
We present results of an independent observational study on CH4 and N2O emissions and
compare them to the reported inventories. We focus on the net emissions from The
Netherlands during the period 2006 to 2008, and how they compare to the surrounding
countries.
To answer these questions we apply 222Radon as a reference tracer for vertical mixing
and long-range air mass transport. 222Radon is a radioactive noble gas (radioactive half-life
time 3.8 days) which is produced at a constant rate from 226Ra, and is relatively uniformly
distributed in all soils. When released to the atmosphere, 222Radon experiences the same
atmospheric circumstances (e.g. transport and dilution) as any other constituent. This makes
it an ideal atmospheric tracer to ‘translate’ ambient concentrations of CH4 and N2O to their
ground-based fluxes, given the 222Radon soil exhalation rate is known. The method used in
this study is purely observationally based and therefore independent from inventories or
models.
Our preliminary results indicate emissions for the period May 2006 – June 2008 of: 15.0
± 0,5 t/km2 for CH4 and 1000 ± 120 kg/km2 for N2O. These values are slightly lower than
the inventory-based emissions of 18,3 t/km2 (2006-2008 averages) for CH4, and 1260 kg/km2
(2006-2008 averages) for N2O. |
|
|
|
|
|
|