Chapter 8.1 - Recalculations

Generally, improvement of the emission inventory is an ongoing task and triggers recalculations for all source categories and pollutants frequently.

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)
• 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.

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 PM_2.5 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

Table 1: Overview of impact of recalculations on the level of National Totals (For more detailed information please mouseclick the pollutant.)

¹: Base Year of reporting: 1990; excumptions: PM_2.5 and PM₁₀: 1995 and BC: 2000

1. revision of activity data

• entire NFR 1.A + 2.C.1: finalisation of National Energy Balance 2019
• NFRs 1.A.3.a i and 1.A.3.a ii (aviation gasoline)
• NFRs 1.A.3.c (solid-fuels), 1.A.3.d
• NFR 3.B, 3.D, 3.D.f & 3.I: updated information and statistical data of the 2020 official agricultural census (e.g. animal numbers, weight data, milk yield: see main agricultural page under „Recalculations and reasons“, Chapter 5 - NFR 3 - Agriculture (OVERVIEW).
• NFRs 5.A, 5.B.1, 5.B.2

2. update or revision of entire model

• NFR 1.A.3.a: revision of TREMOD AV
• NFR 1.A.3.b: revision of TREMOD
• NFRs 1.A.3.d, 1.A.4.c iii and 1.A.5.b iii: revision and correction E.M.M.A. model regarding ship-movement data for maritime navigation activities
• NFR 2.A.5.a: revision of several model parameters

3. newly implemented emission factors

• NFR 2.A.2 + 2.A.3: first use of EF for Carbonmonoxid instead of fuel related estimation
• For urea fertilizer the German fertilizer ordinance prescribes the use of urease inhibitors or the direct incorporation into the soil from 2020 onwards. The NH3 emission factor for urea fertilizers is therefore reduced by 70% from 2020 onwards, see description Chapter 5 - NFR 3 - Agriculture (OVERVIEW).

4. revision of emission factors

• NFR 2.C.7.a: use of new plant specific data for emission factors of TSP, SO₂, As, Cu and Pb in Primary copper production recalculations have been carried out for the entire time series.
• NFR 3: Cattle grazing: The NH₃ emission factors were updated according to EMEP (2019) & and for sheep, laying hens, broilers, pullets: Update of the NH₃ emission factors for manure storage according to EMEP (2019).

5. re-allocation of activity data and emissions

• from NFR 1.B.2.a to NFR 2.B.10: emissions from storage of chemical products

6. as an outcome of the ongoing review activities under both UNFCCC and UNECE

• NFR 1.A.2.f: reporting of CO emissions under NFR 2.A (new estimation)
• NFR 2.C.1: reporting of HCB emissions using standard emission factor for the entire time period