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 (primary) activity data

• 1.A together with 2.C.1: finalisation of National Energy Balance 2021
• 1.A together with 2.C.1: revision of National Energy Balances 2003-2020
• 2.C.2: revised international production statistic 20021
• 2.G.use of charcoal: revised foreign sale statistics 2021

2. update or revision of entire model

• 1.A.3.a: routine revision of TREMOD AV
• 1.A.3.b: routine revision of TREMOD
• 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 MM

3. newly implemented acitivity and/or emission factors

• 1.A.3.d ii: introduction of gasoline and LPG as fuels in domestic inland navigation (as outcome of NEB revision)

4. revision of emission factors

• mobile combustion over-all: revision of (implied) country-specific emission factors as part of model revision
• 2.C.3.a: adjustment of the CO emission factor to national technical guidelines backwards to 1995

5. re-allocation of activity data and/or emissions

• NRMM in 1.A.2.g vii, 1.A.4.a ii and c ii: revision of methodology to distribute over-all fuel deliveries from NEN line 67 onto NRMM-subcategories

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

• emissions from lubricant use: re-allocation from 2.D.3 to NFR 2.G