Modelling the UK reduced nitrogen budget

Citation
Ds. Lee et Rd. Kingdon, Modelling the UK reduced nitrogen budget, PHYS CH P B, 26(10), 2001, pp. 819-824
Citations number
18
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Earth Sciences
Journal title
PHYSICS AND CHEMISTRY OF THE EARTH PART B-HYDROLOGY OCEANS AND ATMOSPHERE
ISSN journal
1464-1909 → ACNP
Volume
26
Issue
10
Year of publication
2001
Pages
819 - 824
Database
ISI
SICI code
1464-1909(2001)26:10<819:MTURNB>2.0.ZU;2-P
Abstract
Currently, more deposition of reduced nitrogen species to the UK is measure d than can be accounted for from the calculated emissions. A newly develope d longrange transport model was used to study this budget. Changes in horiz ontal resolution of model and an improved parameterization of dry depositio n of ammonia gave an improved agreement between measured and modelled depos ition. However, the model still estimated only 65% of the measured depositi on with a UK emissions term of 283 ktonnes N yr(-1). Scaling the emissions by factors of x 1.2 and x 1.3 still resulted in the model underestimating o f reduced nitrogen deposition. Modelled aerosol ammonium and ammonia gas co ncentrations for the base-case were compared with observations. The ammonia gas concentrations appear to be modelled reasonably well but the aerosol a mmonium concentrations were underestimated by a factor of at least 2. This is an important finding as this indicates that other parameters related to wet deposition simulation are unlikely to be in gross error, implying that the UK emissions term is too small. It was concluded that an emission sourc e term of the order 400 ktonnes N yr(-1) is required to reconcile the model with the measurements. Crown Copyright (C) 2001 Published by Elsevier Scie nce Ltd. All rights reserved.