====== Chapter 8.1 - Recalculations ======
{{ :general:recalculations:rueckrechnungen4.png?nolink&200|}}
Generally, improvement of the emission inventory is an ongoing task and triggers recalculations for all source categories and pollutants frequently.
Further information regarding recalculations (especially due to changes in methods or activity data) can be found in the corresponding chapters of the **National Inventory Document 2025** (NID 2025) [(UBA2025)].
===== Possible reasons for Recalculations =====
Due to the ever ongoing efforts to improve the inventory, more or less broad recalculations become necessary with each new submission.
__**Possible reasons for recalculations are**__
* **new** (sub-)**categories** to be included in the inventory or re-allocation of existing sub-categories within the inventory
* **data** (activity data & emission factors) for certain (sub-)categories **available for the first time**
* **change of data sources** (for activity data and emissions)
* use of **new emission factors** (due to: inquest, research projects, expert judgement etc.)
* **improvement of methods** used for calculating emissions
* **outcome of** ongoing **review** activities under both UN FCCC and UN ECE
* etc.
**All these changes can effect //specific years// of the inventory as well as the //entire time series//, leading to more or less significant changes within the emission trends.**
===== Declaration of Recalculations =====
Under UN FCCC reporting, parties have to comment any recalculations in any year leading to differences between latest and current submission for a given year or the time period or series. Thereby, highest attention is given to recalculations within base year and the most current year of the latest submission:
__**Recalculations in Base Year data**__
* mostly rather small but of highest importance
* mostly due to changed methods or emission factors used for entire time series
* impact on basis of any evaluation
__**Recalculations in data of current year of the latest submission**__
* mostly because of **corrected activity data** (especially in Energy Production) from actualized Energy Balances
* also due to changed methods, emission factors, or data sources used
* impact on the amount of emission reduction reported in latest submission
**Under UN ECE, within the IIR**, Germany focusses on recalculations in values reported for **1990** for all MAIN POLLUTANTS, HEAVY METALS and POPS, **1995** for PM2.5 and PM10 and **2000** for BLACK CARBON (BC), and the **last year of the previous submission**, providing the **quantity** (in absolute numbers and in %) of change for any recalculated emission **and the reasons** for the recalculations carried out
===== Recalculations in current submission =====
__Table 1: Overview of impact of recalculations on the level of National Totals__
(For more detailed information please mouseclick the pollutant.)
| for reporting year: |^ BASE YEAR1 |||| ^ 2022 ||||
| |^ prev. subm. ^ curr. subm. ^ ± ^ ± % | ^ prev. subm. ^ curr. subm. ^ ± ^ ± % ^
^ Main pollutants |||||||||||
^ //NEC// |||||||||||
| [[General:Recalculations:nitrogen_oxides| Nitrogen Oxides ]] - NOx (as NO2) | [kt] | 2,842.27 | 2,846.04 | 3.77 | 0.13% | | 941.99 | 926.84 | -15.15 | -1.61% |
| [[General:Recalculations:NMVOC| Non-Methane VOC ]] - NMVOC | [kt] | 3,929.35 | 3,953.69 | 24.3 | 0.62% | | 1,034.51 | 1,051.46 | 16.94 | 1.64% |
| [[General:Recalculations:sulphur_oxides| Sulphur Oxides ]] - SOx (as SO2) | [kt] | 5,459.96 | 5,460.81 | 0.85 | 0.02% | | 255.44 | 246.27 | -9.17 | -3.59% |
| [[General:Recalculations:ammonia| Ammonia ]] - NH3 | [kt] | 734.36 | 834.48 | 100 | 13.6% | | 512.22 | 576.62 | 64.40 | 12.6% |
^ Particulate Matter |||||||||||
| [[General:Recalculations:pm2.5| Particles <2.5µm ]] - PM2.5 | [kt] | 199.77 | 197.47 | -2.30 | -1.15% | | 84.29 | 82.31 | -1.98 | -2.35% |
| [[General:Recalculations:pm10| Particles <10µm ]] - PM10 | [kt] | 337.92 | 334.41 | -3.51 | -1.04% | | 184.56 | 181.99 | -2.57 | -1.39% |
| [[General:Recalculations:TSP| Total Suspended Particles ]] - TSP | [kt] | 2,019.60 | 2,015.59 | -4.01 | -0.20% | | 330.46 | 327.93 | -2.53 | -0.77% |
| [[General:Recalculations:BC| Black Carbon ]] - BC | [kt] | 39.20 | 39.20 | 0.00 | 0.00% | | 9.98 | 10.09 | 0.11 | 1.12% |
^ //**Other**// |||||||||||
| [[General:Recalculations:carbon_monoxide| Carbon Monoxide ]] - CO | [kt] | 13,320.20 | 13,320.53 | 0.33 | 0.002% | | 2,539.17 | 2,568.11 | 28.94 | 1.14% |
^ Heavy Metals |||||||||||
^ //Priority HM// |||||||||||
| [[General:Recalculations:Lead| Lead ]] - Pb | [t] | 1,899.27 | 1,899.27 | 0.00 | 0.00% | | 151.71 | 152.45 | 0.74 | 0.49% |
| [[General:Recalculations:Cadmium| Cadmium ]] - Cd | [t] | 29.10 | 29.10 | 0.00 | 0.00% | | 10.32 | 10.62 | 0.29 | 2.82% |
| [[General:Recalculations:Mercury| Mercury ]] - Hg | [t] | 35.53 | 35.53 | 0.00 | 0.00% | | 6.559 | 6.556 | -0.002 | -0.03% |
^ //Other HM// |||||||||||
| [[General:Recalculations:Arsenic| Arsenic ]] - As | [t] | 85.92 | 85.92 | 0.00 | 0.00% | | 5.58 | 5.76 | 0.18 | 3.19% |
| [[General:Recalculations:Chrome| Chrome ]] - Cr | [t] | 165.69 | 165.69 | 0.00 | 0.00% | | 69.96 | 67.07 | -2.89 | -4.14% |
| [[General:Recalculations:Copper| Copper ]] - Cu | [t] | 619.88 | 619.88 | 0.00 | 0.00% | | 560.30 | 564.60 | 4.30 | 0.77% |
| [[General:Recalculations:Nickel| Nickel ]] - Ni | [t] | 332.75 | 332.75 | 0.00 | 0.00% | | 143.26 | 136.14 | -7.12 | -4.97% |
| [[General:Recalculations:Selenium| Selenium ]] - Se | [t] | 5.73 | 5.73 | 0.00 | 0.00% | | 2.879 | 2.931 | 0.052 | 1.79% |
| [[General:Recalculations:Zinc| Zinc ]] - Zn | [t] | 474.15 | 474.15 | 0.00 | 0.00% | | 292.46 | 296.03 | 3.58 | 1.22% |
^ Persistent Organic Pollutants - POPs |||||||||||
| [[General:Recalculations:Dioxines| Dioxines & Furanes ]] - PCDD/F | [g] | 805.10 | 805.10 | 0.00 | 0.00% | | 107.67 | 112.50 | 4.83 | 4.48% |
^ //Polycyclic Organic Hydrocarbons - PAHs// |||||||||||
| [[General:Recalculations:BaP| Benzo(a)pyrene ]] - B[a]P | [t] | 26.99 | 26.99 | 0.00 | 0.00% | | 17.94 | 18.81 | 0.87 | 4.87% |
| [[General:Recalculations:BbF| Benzo(b)fluoranthene ]] - B[b]F | [t] | 35.83 | 35.83 | 0.00 | 0.00% | | 26.02 | 27.30 | 1.28 | 4.92% |
| [[General:Recalculations:BkF| Benzo(k)fluoranthene ]] - B[k]F | [t] | 16.26 | 16.26 | 0.00 | 0.00% | | 11.83 | 12.39 | 0.57 | 4.80% |
| [[General:Recalculations:IxP| Indeno(1,2,3-c,d)pyrene ]] - I[1,2,3-c,d]P | [t] | 23.03 | 23.03 | 0.00 | 0.00% | | 17.28 | 18.15 | 0.86 | 5.00% |
| [[General:Recalculations:PAH| Polycyclic Aromatic Hydrocarbons ]] - PAH 1-4 | [t] | 115.67 | 115.67 | 0.00 | 0.00% | | 76.74 | 80.27 | 3.53 | 4.60% |
^ //Other POPs// |||||||||||
| [[General:Recalculations:HCB| Hexachlorobenzene ]] - HCB | [kg] | 2,900.52 | 2,900.52 | 0.00 | 0.00% | | 4.63 | 4.68 | 0.04 | 0.94% |
| [[General:Recalculations:PCB| Polychlorinated Biphenyls ]] - PCBs | [kg] | 1,735.78 | 1,735.78 | 0.00 | 0.00% | | 213.40 | 209.46 | -3.94 | -1.85% |
| 1: Base Year of reporting: 1990; excumptions: PM2.5 and PM10: 1995 and BC: 2000 |||||||||||
===== Overview of reasons for recalculations against Submission 2024 =====
(main changes only, without claim to completeness)
**1. revision of (primary) activity data**
* 1.A together with 2.C.1: __finalisation of National Energy Balance__ 2022 [(AGEB2024)]
* 2.A.2 and 2.A.3: small updates of statistical data for most recent years
* 3.B.4.e: Horse numbers were corrected in all years and all districts by a factor of 2.75 to include horses which are kept outside of agricultural holdings and not counted by agricultural census
**2. update or revision of entire model**
* 1.A.3.a: routine revision of TREMOD Aviation (TREMOD AV) [(ALLEKOTTE2024)]
* 1.A.3.b: routine revision of TREMOD [(KNOERR2024a)]
* 1.A.2.g vii, 1.A.4.a ii, 1.A.4.b ii and 1.A.4.c ii: routine revision of TREMOD Mobile Machinery (TREMOD MM) [(KNOERR2024b)]
* 1.A.3.d: routine revision of E.M.M.A. model maintained at BSH [(DEICHNIK2024)]
**3. newly implemented acitivity and/or emission factors**
* 3.D.a.1: NH3 emission factors for mineral fertilizers in EMEP (2023) were used for the first time in the present submission.
* 3.D.a.4: NH3 emissions from crop residues are calculated for the first time according to the tier 2 method from EMEP (2023). Cover crops are also a newly reported source of PM emissions from soils.
**4. revision of emission factors**
* mobile combustion over-all: revision of (implied) country-specific emission factors as part of model revision
* 1.A.3.b i, ii, iv, vi, vii, and 1.A.3.d.i (i): correction of rounding errors in emission factors for B[a]P, B[b]F, B[k]F, I[x]P, and PAH1-4
* 1.A.3.c - abrasive particulate matter: consideration of new (and far lower) emission factors for PM10 from the abrasion of wheel on rail from a corresponding measurement campaign as part of a research project [(DZSF2025)]
* 3.B: improved emission factors for cattle and pig housing were introduced based on national research projects
* 3.B: N2O emission factors were adopted from the IPCC Refinement (2019). The N2O EF for solid manure storage doubles, which then also applies to the corresponding NOx and N2 EFs.
**5. re-allocation of activity data and/or emissions**
*
**6. as an outcome of the ongoing review activities under both UNFCCC and UNECE**
*
[(AGEB2024>AGEB, 2024: Working Group on Energy Balances (Arbeitsgemeinschaft Energiebilanzen (Hrsg.), AGEB): Energiebilanz für die Bundesrepublik Deutschland;
https://ag-energiebilanzen.de/wp-content/uploads/2024/03/EBD22e.xlsx, (Aufruf: 04.12.2024), Köln & Berlin, 2024)]
[(KNOERR2024a> Knörr et al. (2024a): Knörr, W., Heidt, C., Gores, S., & Bergk, F.: Fortschreibung des Daten- und Rechenmodells:
Energieverbrauch und Schadstoffemissionen des motorisierten Verkehrs in Deutschland 1960-2035, sowie TREMOD, im Auftrag des Umweltbundesamtes, Heidelberg [u.a.]:
Ifeu Institut für Energie- und Umweltforschung Heidelberg GmbH, Heidelberg & Berlin, 2024.)]
[(KNOERR2024b>Knörr et al. (2024b): Knörr, W., Heidt, C., Gores, S., & Bergk, F.: ifeu Institute for Energy and Environmental Research (Institut für Energie- und Umweltforschung Heidelberg gGmbH, ifeu): Aktualisierung des Modells TREMOD-Mobile Machinery (TREMOD MM) 2024, Heidelberg, 2024.)]
[(ALLEKOTTE2024> Allekotte et al. (2024): TREMOD Aviation (TREMOD AV) - Revision des Modells zur Berechnung des Flugverkehrs (TREMOD-AV). Heidelberg,
Berlin: Ifeu Institut für Energie- und Umweltforschung Heidelberg GmbH & Öko-Institut e.V., Berlin & Heidelberg, 2024.)]
[(DEICHNIK2024> Deichnik (2024): Aktualisierung und Revision des Modells zur Berechnung der spezifischen Verbräuche und Emissionen des von Deutschland ausgehenden Seeverkehrs.
from Bundesamts für Seeschifffahrt und Hydrographie (BSH - Federal Maritime and Hydrographic Agency); Hamburg, 2024.)]
[(DZSF2025> DZSF (Deutsches Zentrum für Schienenverkehrsforschung / German Centre for Rail Traffic Research) research project on "Size-specific and spatial distribution of traffic-related abrasion and particulate emissions" (Größenspezifische und räumliche Verteilung von verkehrsbedingten Abrieben und partikulären Emissionen) https://www.dzsf.bund.de/SharedDocs/Standardartikel/DZSF/Projekte/Projekt_44_Abriebe_Emissionen.html )]
[(UBA2025> UBA, 2025: National Inventory Document for the German Greenhouse Gas Inventory 1990-2023 (NID 2025), https://www.umweltbundesamt.de/themen/klima-energie/treibhausgas-emissionen?listpart=1#articlelist, Dessau, April 2025)]