Spatial and temporal variations in ammonia emissions – a freely accessible model code for Europe

Abstract

Deriving a parameterisation of ammonia emissions for use in chemistry-transport models (CTMs) is a complex problem as the emission varies locally as a result of local climate and local agricultural management. In current CTMs such factors are generally not taken into account. This paper demonstrates how local climate and local management can be accounted for in CTMs by applying a modular approach for deriving data as input to a dynamic ammonia emission model for Europe. Default data are obtained from information in the RAINS system, and it is demonstrated how this dynamic emission model based on these input data improves the NH<sub>3</sub> calculations in a CTM model when the results are compared with calculations obtained by traditional methods in emission handling. It is also shown how input data can be modified over a specific target region resulting in even further improvement in performance over this domain. The model code and the obtained default values for the modelling experiments are available as supplementary information to this article for use by the modelling community on similar terms as the EMEP CTM model: the GPL licencse v3

Retrieval of ammonia from ground-based FTIR solar spectra

“…To improve on static emission time profiles, a new direction is to include the impact of the meteorological variability of ammonia emissions in modelling systems . Recently, such an improvement was shown to greatly enhance the performance of air quality models (Skjøth et al, 2011). Satellite observations in combination with chemical transport models (CTM) have been used to provide a top-down constraint on ammonia emissions (e.g.…”

Advances in understanding, models and parameterizations of biosphere-atmosphere ammonia exchange

“…3.3), this is a landscape scale issue, but it is also a CTM issue, because (i) failing to reproduce local NH 3 budgets affects the predictive capability of regional modelling, and (ii) CTMs must be used to derive critical loads exceedance maps at national and regional scales in support of environmental policy development. Improving the performance of high-resolution localscale models requires high quality emission inventories with sufficiently high spatial resolution (Skjøth et al, 2011). In addition, a high temporal resolution for emissions is also crucial for the performance of CTMs, and dynamic calculations of NH 3 emissions are needed for a better prediction of high particulate matter episodes (Menut and Bessagnet, 2010;Henze et al, 2009).…”

Evaluation of a regional air-quality model with bidirectional NH<sub>3</sub> exchange coupled to an agroecosystem model

“…NH 3 emission inventories for regional air-quality models have been developed based on annual fertilizer sales and animal density with spatial resolution at the US county level and monthly temporal resolution (Goebes et al, 2003;Pinder et al, 2004), and from mechanistic models based on reported agricultural data and semiempirical relationships between emissions and meteorological observations with spatial resolution as fine as 50 km by 50 km and hourly temporal resolution (Skjøth et al, 2011). The improvements in spatial and temporal resolution and top down inverse modeling constraints on NH 3 emissions have improved air-quality models' skill regarding the estimation of NH 3 and aerosol NH + 4 concentrations (Skjøth et al, 2011;Pinder et al, 2006;Gilliland et al, 2006). Despite these model improvements, a systematic difference between ambient NH 3 observations and model estimates on the order of 30 % persists (Erisman et al, 2007).…”