Chapter 8.1 - Recalculations

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 chapter of the National Inventory Report.

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 dislocation of subcategories 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 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: finalisation of National Energy Balance 2018
• NFRs 1.A.3.a i and 1.A.3.a ii: revision of percental shares of both jet kerosene and avition gasoline allocated to international and domestic flights
• NFRs 1.A.3.b vi & vii: revision of annual mileage data for different road vehicles
• several NFR categories: revision of population data: The population in Germany has been subject to several evaluations in recent years. In the meantime, the methodology for the so-called “Census 2011” has been confirmed by the Federal Constitutional Court in the final instance with a representative survey and extrapolation by the Federal Statistical Office. On this basis, the Federal Statistical Office examined correction options for previous years and published a so-called “recalculated and extrapolated population on the basis of the 2011 census”. This recalculation up to and including 1991 eliminates the gap between the 2010 population updates and the 2011 census results. The inventory team of the Single National Entity has decided to use this corrected population time series for all relevant calculations. As a result, various time series have been recalculated from 1991 up to and including 2016.
• NFR 3.B, 3.D & 3.I: updated information and statistical data (e.g. animal numbers, weight data, milk yield: see main agricultural page under „Recalculations and reasons“, Chapter 5 - NFR 3 - Agriculture (OVERVIEW)

2. update or revision of entire model

• NFR 1.A.3.a: revision of TREMOD AV
• NFR 1.A.3.b: revision of TREMOD
• NFR 3 in general, the model GAS-EM was updated (e.g. correction of the calculation of the TAN excretion of dairy cows and the TAN flow into manure storage of male beef cattle, heifers: subdivision into dairy and slaughter heifers with different final weights; adaptation of energy requirements and feeding according to German expert recommendations, see description Chapter 5 - NFR 3 - Agriculture (OVERVIEW)

3. newly implemented emission factors

4. revision of emission factors

• NFR 1.A.3.b vi & vii: revised tier1 emission factors for abrasive heavy metals and POPs emissions from research study
• 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

• NFR 1.A.3.a: distribution of avgas inland deliveries onto all four sub-categories (until submission 2020: 100% of avgas allocated to NFR 1.A.3.a ii (i))

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