===== 6.A.1 - Ammonia emissions from human respiration and transpiration =====

====Short description ====

^  Category Code                          ^  Method  ^  AD  ^  EF  ^
|  6.A.1                                  |  T1      |  NS  |  D   |
|  {{page>general:Misc:LegendEIT:start}}                        ||||

\\

|  NO<sub>x</sub>                         |  NMVOC  |  SO<sub>2</sub>  ^  NH<sub>3</sub>  |  PM<sub>2.5</sub>  |  PM<sub>10</sub>  | TSP  |  BC  |  CO  |                          Heavy Metals |||||||||  POPs  |
|  NA                                     |  NA     |  NA              ^  -/-             |  NA                |  NA               |  NA  |  NR  |  NA  |  NA                                   |||||||||  NA    |
|  {{page>general:Misc:LegendKCA:start}}                                                                                                                                                       |||||||||||||||||||

In addition to animal-related excretion, nitrogen (N) is also introduced into the environment through human consumption of food and later disposed of. 

Although nitrogen is released into the wastewater system as urine, mainly, physiological processes such as sweating and respiration also release nitrogen as ammonia. 


====Methodology====

The calculation of ammonia emissions in this area is made for the first time and is based on the methodological description of Visschendijk et al. (2022) ((Visschedijk, A.J.H., J.A.J. Meesters, M.M. Nijkamp, W.W.R. Koch, B.I. Jansen & R. Dröge, 2022. Methods used for the Dutch Emission Inventory. Product usage by consumers, construction and services. RIVM Report 2022-0003. RIVM, Bilthoven., chapter 19 [https://rivm.openrepository.com/bitstream/handle/10029/625730/2022-0003.pdf?sequence=1&isAllowed=y])).

For the complete time series, the emissions are calculated as follows: 

<WRAP center round info 40%>
<m 30%>
EM = AD_(number of German inhabitants) * EF_(kg emission per inhabitant)</m>
</WRAP>

===Activity data ===

The number of inhabitants in Germany is derived from the Federal Statistical Office of Germany (DESTATIS) on an annual basis. 

The number of people living in Germany by end of June of a specific year is taken as activity data. 
As of June 2022, 84,4 million people lived in Germany. 

The following table shows the population figures over time.

__Table 1: Population figures in Germany, as of 1990__
^  1990  ^  79,753,227  ^
^  1995  ^  81,307,715  ^
^  2000  ^  81,456,617  ^
^  2005  ^  81,336,663  ^
^  2010  ^  80,284,071  ^
|  2011  |  80,274,983  |
|  2012  |  80,523,746  |
|  2013  |  80,767,463  |
|  2014  |  81,197,537  |
^  2015  ^  82,175,684  ^
|  2016  |  82,521,653  |
|  2017  |  82,792,351  |
|  2018  |  83,019,213  |
|  2019  |  83,166,711  |
^  2020  ^  83,155,031  ^
^  2021  |  83,237,124  |
^  2022  ^  84,358,845  ^

===Emission factor===

For the calculation of ammonia emissions in this category, the highest of the emission factors given in Sutton et al. (2000)((Sutton, M.A., U. Dragosits, Y.S. Tang & D. Fowler, 2000. Ammonia emissions from non-agricultural sources in the UK. 

Atmospheric Environment 34 (2000), 855–869.)) are used, resulting in a total emission factor of 0.0826 kg NH<sub>3</sub>-N per person per year (according to the assumptions sum of 74.88 (sweating) and 7.7 (breathing) grams NH<sub>3</sub>-N per person per year, respectively). 

Here, to avoid underestimating of emissions, the higher EFs were applied. 

The amount was converted to the amount of ammonia using the stoichiometric factor of 17/14.

====Emission Trend====

The average value over tha last decade is 8.25 kt NH<sub>3</sub> / year, so this category is not a major source of regional NH<sub>3</sub> emissions. 

The following figure shows the emission trend as of 1990:

{{ :sector:other_and_natural_sources:other_sources:em_nh3_6.a.1.png?800 | Annual ammonia emissions from human re- and transpiration. }}

===== Recalculations =====

<WRAP center round info 65%>
With **activity data and emission factors remaining unrevised**, no recalculations were made compared to the last submission.
</WRAP>


==== Uncertainties ====

Activity data obtained from the Federal Statistical Office of Germany (DESTATIS) usually have an uncertainty of ±3%.

As emission factors vary between different data sources and the amount of ammonia volatilized is based on an assumption, uncertainties for the emission factors are expected to be relatively high. 

Hence the overall uncertainty for the emission estimation of NH<sub>3</sub> is estimated by expert judgement to be ±95%.

====Planned Improvement====

<WRAP center round info 60%>
Currently, no source-specific improvements are planned.
</WRAP>