Distr.

GENERAL



FCCC/SBSTA/1999/INF.3

25 February 1999



ENGLISH ONLY


SUBSIDIARY BODY FOR SCIENTIFIC AND TECHNOLOGICAL ADVICE

Tenth session

Bonn, 31 May - 11 June 1999

Item 4 (a) of the provisional agenda

 



 

NATIONAL COMMUNICATIONS FROM PARTIES INCLUDED

 

IN ANNEX I TO THE CONVENTION



 

GUIDELINES FOR THE PREPARATION OF NATIONAL COMMUNICATIONS



 

Effects of recalculations of the greenhouse gas inventories of the base and

subsequent years on assigned amounts and on emission limitation and

reduction commitments of Annex I Parties



 

Note by the secretariat



 

CONTENTS

Paragraphs Page



I. INTRODUCTION 1 - 10 2

 

A. Mandate 1 2

B. Background 2 - 3 2

C. Scope of the note 4 - 5 2

D. Possible action by the SBSTA 6 3

E. Approach 7 - 10 3



II. ASSESSMENT OF THE EFFECTS OF RECALCULATION 11 - 20 4



A. Effects of recalculations on simulated assigned amounts 11 - 16 4

B. Effects of recalculations on simulated commitments

by Parties 17 - 20 8



III. CONCLUSIONS 21 - 23 17

GE.99-

 

I. INTRODUCTION



 

A. Mandate

 

1. The Subsidiary Body for Scientific and Technological Advice (SBSTA), at its eighth session, requested the secretariat to organize a workshop with the participation of methodological experts from the roster, as well as from other relevant organizations, to develop proposals to resolve the methodological issues identified by Parties and by the secretariat while processing greenhouse gas (GHG) inventories included in second national communications (FCCC/SBSTA/1998/6, para. 40 (d)).



 

B. Background



2. In response to the above mandate, as part of the work programme on methodologies, the secretariat prepared an informal paper: "Effects of recalculations of the GHG inventories of the base and subsequent years on assigned amounts and on emission limitation and reduction commitments of Annex I Parties" for consideration by the experts of the roster attending the workshop on methodological issues. The secretariat prepared this paper to promote an understanding of the possible effects of recalculations of the base and subsequent years' GHG inventories on the assigned amounts and on the emission limitation and reduction commitments of Annex I Parties under the Kyoto Protocol.



3. As requested, the secretariat organized a workshop on methodological issues related to GHG inventories, which was held in Bonn, from 9 to 11 December 1998. This paper, a revised version of the informal paper, considers comments provided by experts from the roster. It is reproduced as an official note prepared by the secretariat.

 

C. Scope of the note



4. This paper provides information on methodological issues related to the recalculation of GHG inventories for the base and subsequent years. Recalculation of the base year was identified by the secretariat as a relevant methodological issue while processing GHG inventory data (see documents FCCC/SBSTA/1998/7 and FCCC/SBSTA/1998/8).



5. The secretariat used the GHG inventory data from the first national communications, referred to below as NC1 and the second national communications, referred to below as NC2, to prepare this paper.(1)



D. Possible action by the SBSTA



6. The SBSTA may wish to consider the information provided in this note and to determine the need for additional analyses. It may wish to provide guidance to the secretariat on any future analyses, including the questions it wishes the secretariat to address, such as the consideration of the issue of recalculations in the work programme on methodological issues related to Articles 5, 7 and 8 of the Kyoto Protocol (FCCC/SB/1999/2). For example, it may be interesting to assess the impact of recalculations of the base and subsequent years resulting from the use of different GHG inventory methods/data in second (NC2) and third national communications (NC3) on Parties' assigned amounts and on Parties' ability to meet their commitments. Such an assessment could consider complete sets of five-year inventory data for all Annex I Parties if possible, instead of the limited inventory data used in this note. Such analyses could be reflected in the work programme of the secretariat for the next biennium.



 

E. Approach



7. The approach applied in this paper assesses the effects of recalculations using actual inventory data reported by Parties. The intent is to assess whether and how changes in methods/data could affect the estimation of assigned amounts and the extent to which Parties could meet simulated commitments similar to those in the Kyoto Protocol. It was developed to enable potential methodological problems to be identified before the first commitment period.



8. Terms used in the Kyoto Protocol, such as assigned amounts, commitments and commitment period, were applied in this paper, for years and contexts other than those in the Protocol. The term "simulated" is used in the paper to denote this difference. The simulated assigned amounts and commitments were used in this paper only with the purpose of identifying potential methodological problems.



9. According to Article 7.4 of the Kyoto Protocol, the Conference of the Parties serving as the meeting of the Parties to the Protocol (COP/MOP) shall decide upon modalities for the accounting of assigned amounts. The term "simulated assigned amount" as used in this paper is intended to estimate this assigned amount in a manner similar to that described in Article 3.7 of the Kyoto Protocol, although the COP/MOP has not decided yet upon modalities for accounting.



10. Parties have a commitment under the Kyoto Protocol to limit their GHG emissions to those of an agreed assigned amount. The term "simulated commitment" as used in this paper is intended to represent a "what if" situation, wherein the Parties might have agreed to their

Kyoto Protocol commitments for the period 1991-1994 relative to a base year of 1990. The related simulated assigned amount needed to establish the simulated commitment was also estimated for the same period 1991-1994.



 

II. ASSESSMENT OF THE EFFECTS OF RECALCULATION



 

A. Effects of recalculations on simulated assigned amounts



 

1. Recalculations



11. All Parties recalculated their GHG inventories between the NC1 and the NC2 (FCCC/SBSTA/1998/7, para. 24). The differences between the estimates were influenced by two factors. First, global warming potential (GWP) values changed between the first national communications and the second national communications. Secondly, Parties changed methods, emission factors, assumptions and activity data and added new sources. These latter changes, which are referred to in this paper as "change in methods/data", are encouraged by the Intergovernmental Panel on Climate Change (IPCC) Guidelines for National Greenhouse Gas Inventories with a view to improving the quality and accuracy of inventories. Table 1 indicates the magnitude of changes for carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) emission base year estimates and their effect on the aggregate CO2 equivalent emission estimates between NC1s and NC2s.(2)



12. No further changes in GWP values are expected until the end of the first commitment period under the Kyoto Protocol. It should be noted that decision 2/CP.3 of the Conference of the Parties (COP) reaffirmed that Parties should use the 1995 IPCC GWP values based on the effects of the greenhouse gases over a 100-year time horizon (FCCC/CP/1997/7/Add.1). Furthermore, Article 5.3 of the Kyoto Protocol states that this GWP shall be used for the duration of the first commitment period. However, recalculations due to changes in methods/data are expected under the current practice of preparing GHG inventories.



 

2. Estimation of assigned amounts



13. Simulated assigned amounts are presented in this paper. They were estimated in a manner similar to that described in Article 3.7 of the Kyoto Protocol(3) using the following formula:



Assigned amount = 5 x [CO2 equivalent emission estimates of the base year] x [ 0.01] x [quantified emission limitation or reduction commitment inscribed in Annex B of the Kyoto Protocol](4)



14. The simulated assigned amounts were calculated as aggregate GHG emissions expressed as CO2 equivalent for the base year using data from NC1s and NC2s of Annex I Parties. In both cases, the 1995 IPCC GWP values were used, to exclude the effect of using different GWPs. Therefore, changes in the aggregate GHG emissions in the year 1990, and correspondingly in the simulated assigned amounts, between the NC1 and the NC2 are a consequence only of change in methods/data. To carry out the calculations, the secretariat's database was used. Since only eight Parties provided emissions data on hydrofluorocarbons (HFCs), perfluorocarbons (PFCs) and sulphur hexafluoride (SF6) in their NC1, these GHGs were not considered for the calculations in this paper for the sake of consistency.



15. A comparison between simulated assigned amounts of 28 Parties calculated using data from NC1s and NC2s is shown in table 2. The absolute values of these amounts are presented in columns A and B of the table, differences resulting from changes in methods/data between the NC1 and the NC2 are presented as Gg of aggregate GHG emissions in terms of CO2 equivalent in

column C and as percentages in column D.



16. The percentage differences between those simulated assigned amounts mentioned in paragraph 13 above are almost identical(5) to the differences due to changes in methods/data of the aggregate CO2 equivalent estimates for the year 1990 between the NC1s and the NC2s

(see table 1, column F). For Parties with higher or lower CO2 equivalent estimates in their NC2 than their NC1, their assigned amount was correspondingly higher or lower. So, a change in the given value of the base year has a direct impact on the size of the assigned amount and hence the size of the assigned amount is dependent on changes in methods/data applied to the base year.



Table 1. Differences in GHG emission estimates for the year 1990 due to changes in

methods/data used (percentage change)a



A

B

C

D

E

F

Party

All GHG emission estimates

(CO2 equivalent)

CO2 emission

estimates

CH4 emission

estimates

N2O emission

estimates

Total change

Effect of the use of different GWPs

Effect of changes in methods/

data

Australia

-5.5

-17.1

31.4

-12.1

-4.4

-7.7

Austria

4.5

-2.6

183.2

3.4

-2.7

6.1

Bulgaria

-0.7

0.8

31.6

-2.6

-4.1

1.5

Canada

<1

3.6

-9.9

-1.9

-2.1

0.2

Czech Republic

<1

-5.8

7.5

-2.2

-1.8

-0.4

Denmark

<1

3.4

230.1

9.7

-2.5

12

Estonia

--

-67.4

-4.2

-2.4

-2.8

0.4

Finland

<1

-2.4

-18.2

-3.8

-1

2.8

France

3.2

4.2

2.8

0.8

-2.4

3.2

Germany

--

--

7.1

-1.4

-1.8

0.4

Greece

3

29.2

26

4.6

-1.7

6.3

Iceland

-1.1

-39.1

-30

-12.2

-2

-10.2

Ireland

--

1.9

-30.6

-10.8

-5.2

-5.6

Italy

<1

-40.3

36.7

-5.5

-1.8

-3.7

Japan

-2.6

14

90.8

-1.3

-0.6

-0.7

Latvia

7.8

17.2

838.8

29

-2.4

31.4

Luxembourg

16.3

0.5

14.5

14.7

-0.7

15.4

Netherlands

--

4.1

-0.6

-1.6

-2.1

0.5

New Zealand

--

-14.1

177.9

-4.5

-7.82

3.32

Norway

<1

49

--

3.9

-3.3

7.2

Portugal

11.8

257.7

33.3

34.1

-4.2

38.3

Russian Federation

<1

-1.9

151.9

-2.6

-3.1

0.5

Slovakia

3

17.9

-21.9

0.8

-2.1

2.9

Spain

<1

1.4

0.3

-2.8

-2.8

0

Sweden

-9.5

-1.5

-39.5

-12.2

-1.9

-10.3

Switzerland

--

-26.7

-26.3

-7.6

-1.8

-5.8

United Kingdom

1.2

-1.5

10.8

-1.1

-2.3

1.2

United States

<1

9.5

3.3

-0.6

-1.9

1.3



a Percentage deviation of the inventory of the NC2 relative to the inventory submitted in the NC1. Negative values denote that the later inventory has a lower figure. All figures rounded. Where no value is shown this indicates that the difference is zero between the emissions in the NC1 and the NC2.



Table 2. Comparison between the simulated assigned amounts calculated using inventory

data of the year 1990 from first and second national communications



A

B

C

D

Party

Simulated assigned amounts for the first commitment period

(CO2 equivalent)

Differences between the simulated assigned amounts estimated using data from NC1s and NC2s due to change in methods/dataa

B-A

(C/A)*100

NC1

NC2

[Gg]

[Gg]

[Gg]

[per cent]

Austria

336 416

357 944

21 528

6.4

Canada

2 618 351

2 621 942

3 591

0.1

Czech Republic

887 864

883 798

-4 066

-0.5

Denmark

293 319

329 627

36 308

12.4

Estonia

208 490

187 307

-21 183

-10.2

Finland

303 655

296 912

-6 744

-2.2

France

2 217 793

2 291 108

73 315

3.3

Germany

5 514 880

5 536 270

21 390

0.4

Greece

430 330

456 467

26 137

6.1

Iceland

15 626

14 141

-1 485

-9.5

Ireland

278 521

261 561

-16 960

-6.1

Italy

2 521 513

2 447 421

-74 092

-2.9

Japan

5 645 330

5 594 175

-51 155

-0.9

Latvia

124 471

164 077

39 606

31.8

Luxembourg

55 352

63 977

8 625

15.6

Netherlands

946 795

950 369

3 574

0.4

New Zealand

362 415

380 170

17 755

4.9

Norway

233 583

248 793

15 211

6.5

Portugal

230 685

314 833

84 148

36.5

Russian Federation

14 917 480

14 993 835

76 355

0.5

Slovakia

324 415

333 482

9 067

2.8

Spain

1 387 369

1 386 583

-787

-0.1

Sweden

335 234

299 465

-35 770

-10.7

Switzerland

261 639

247 245

-14 393

-5.5

United Kingdom

3 246 386

3 287 579

41 193

1.3

United States

26 279 735

26 566 938

287 203

1.1



a Differences in CO2 equivalent estimates for the year 1990 are only a consequence of change in methods/data. Both estimates were calculated using 1995 GWPs and, therefore, the effect of using different GWPs was excluded. Negative values in the difference denote that the simulated assigned amounts calculated using the data of the NC2 are lower than those calculated using the data of the NC1.



 

B. Effects of recalculations on simulated commitments by Parties

17. Simulated assigned amounts, using data from NC1s and NC2s were calculated, in line with the Kyoto Protocol. It was assumed that these simulated assigned amounts related to the years 1991 to 1994, simply because actual inventory data from the NC1s were available only for this period.(6) To assess the extent to which a Party may go over or under its simulated assigned amount, the ratio between total emissions in the simulated commitment period and the simulated assigned amounts were calculated. This exercise was carried out for data from NC1s and NC2s. Comparisons allow for an assessment of the effects of recalculations of the inventory data owing to changes in methods/data between those national communications.

18. The results of this exercise are presented in table 3. Columns A and B show simulated assigned amounts for the simulated commitment period of 1991 to 1994,(7) (or 1991 to 1993(8)), expressed as CO2 equivalent GHG emissions. The year 1990 was used as a base year when calculating the simulated assigned amounts. Columns A and B represent the simulated assigned amounts based on 1990 data in the NC1 and the NC2 respectively. Actual emission estimates from NC1s and NC2s for the same period are presented in columns C and D. A comparison of actual data with the simulated assigned amounts in columns E and F indicates the percentage by which Parties are under or over the simulated commitments. The final column shows the difference in these results. It can be observed that in most cases the difference, which reflects changes in methods/data, is lower than one percentage point.(9)

19. On the basis of the data presented in table 3, a number of figures were prepared to facilitate further understanding of effects of the recalculations on the commitments under the Kyoto Protocol. Three figures were prepared for each Party:

(a) The first figure (e.g., 1a) shows the trend of aggregate GHG emissions (CO2, CH4, N2O), expressed in CO2 equivalent, based on data from the NC1 and the NC2;

(b) The second figure (e.g., 1b) shows in absolute terms the extent by which the Party either goes over or under a simulated commitment, given data in either the NC1 or the NC2. It shows the amount of CO2 equivalent emissions by which the total GHG emissions of the simulated commitment period were higher (positive value) or lower (negative value) than the simulated assigned amounts. The values were calculated by subtracting columns A from C and B from D in table 3.

(c) The third figure (e.g., 1c) shows similar information, but in percentage terms. It represents the values contained in columns E and F of table 3. For example, during the simulated commitment period, Canada exceeded its simulated assigned amount by 9 per cent according to data in its NC1 (column E in table 3) and by 8.4 per cent according to data in its NC2 (column F in table 3). The percentage over or under this simulated commitment was altered by -0.6 percentage points in this case as a consequence of recalculations (column G in table 3).

20. In addition, figures 14 and 15 were prepared to illustrate the understanding of the results presented in table 3 which were obtained using the calculations described in paragraphs 15, 16, 17(b) and 17(c) above.



Table 3. Possible impact of recalculations on simulated commitments

Party

A

B

C

D

E

F

G

Simulated assigned amounts for a simulated commitment period 1991 to 1994 (1993), (CO2 equivalent)

Total GHG emission estimates for the period 1991 to 1994 (1993),

(CO2 equivalent)

Percentage over/under simulated commitments

Differences between percentages over/under simulated commitmentsa

NC1

NC2

NC1

NC2

NC1

NC2

100*

(C-A)/A

100*

(D-B)/B

(F-E)

[Gg]

[Gg]

[Gg]

[Gg]

[per cent]

[per cent]

[percentage points]

Canada

2 094 681

2 097 554

2 283 421

2 274 230

9

8.4

-0.6

Denmark

234 655

263 701

285 604

321 162

21.7

21.8

0.1

Estonia

166 792

149 846

127 726

119 035

-23.4

-20.6

2.8

France

1 330 676

1 374 665

1 469 644

1 524 409

10.4

10.9

0.5

Germany

3 308 928

3 321 762

3 321 707

3 350 547

0.4

0.9

0.5

Iceland

9 375

8 484

8 485

7 791

-9.5

-8.2

1.3

Japan

3 387 198

3 356 505

3 673 120

3 649 804

8.4

8.7

0.3

Netherlands

757 436

760 295

860 412

858 350

13.6

12.9

-0.7

New Zealand

289 932

304 136

290 704

302 067

0.3

-0.7

-1

Norway

186 866

199 035

183 435

196 809

-1.8

-1.1

0.7

Switzerland

209 311

197 796

226 073

214 140

8.0

8.3

0.3

United Kingdom

2 597 108

2 630 063

2 737 962

2 746 151

5.4

4.4

-1.0

United States

21 023 788

21 253 550

22 867 165

23 218 753

8.8

9.2

0.4



a The value was calculated by subtracting the values of column F ( percentage over/under simulated commitments calculated using data from NC2) from column E ( percentage over/under simulated commitments calculated using data from NC1). The difference between two percentages is expressed in percentage points. The resulting values can be directly compared to the quantified emission limitation or reduction commitments inscribed in Annex B of the Kyoto Protocol, such as +10 per cent for Iceland and -8 per cent for Switzerland.



FIGURES

Figures a - Trends in aggregate GHG emissions expressed in CO2 equivalent (Gg) for the years 1990 to 1994.

Figures b - Amount of aggregate GHG emissions by which the Party either over- or under-achieved its simulated commitment, given data in either the NC1 or the NC2 (CO2 equivalent in Gg).

Figures c - Percentage over or under simulated commitments and differences between these levels (in percentage points).

These figures are not available in html format



 

III. CONCLUSIONS

21. Base year inventory data can change significantly as a result of recalculations due to new methods/data. Since the assigned amounts under the Kyoto Protocol in mass units are calculated using base year inventory data, these too can change significantly.

22. For thirteen Parties, a simulated assigned amount for a simulated commitment period was estimated using 1990 inventory data in NC1s and as recalculated in NC2s. The assigned amounts were then compared to the actual inventory data for the period 1991-1994 as reported in NC1s and NC2s. Furthermore, the extent by which Parties either go over or under simulated commitments for this simulated commitment period was estimated in relative terms to the assigned amounts.(10) The results indicate that for thirteen Parties, changes in methods would cause these Parties to go over or under their simulated commitments by +2.9 to -1.0 additional percentage points.

23. The results seem to indicate that the absolute changes in assigned amounts used in the assessment of Parties' commitments may be significant, given a change in methods/data in the inventory. The overall effect of changes in methods, if applied consistently to emission estimates during a commitment period, may be less significant. Nevertheless, such changes in methods may need to be considered by Parties, as even small changes may affect a Party's ability to meet its commitments.



 

- - - - -

1. Supplementary and updated inventory data submitted to the secretariat after the submission of NC2 were not considered for the purpose of this paper.

2. This table is reproduced from document FCCC/SBSTA/1998/7, page 31. It gives detailed information on how the table 11 was prepared.

3. Article 3.7 defines the assigned amount as follows: AIn the first ... commitment period, from 2008 to 2012, the assigned amount for each Party included in Annex I shall be equal to the percentage inscribed for it in Annex B of its aggregate anthropogenic carbon dioxide equivalent emissions of the greenhouse gases listed in Annex A in 1990, or the base year or period determined in accordance with paragraph 5 above, multiplied by five. Those Parties included in Annex I for whom land-use change and forestry constituted a net source of greenhouse gas emissions in 1990 shall include in their 1990 emissions base year or period the aggregate anthropogenic carbon dioxide equivalents emissions by sources minus removals by sinks in 1990 from land-use change for the purposes of calculating their assigned amount".

4. In the light of the ongoing work on methodological issues related to the estimation and reporting of emissions by sources and removals by sinks from the land-use change and forestry sector, this report does not provide information on emissions or removals from this sector. Also for this reason, in this report the simulated assigned amounts do not consider emissions from the land-use change and forestry sector, although Article 3.7 of the

Kyoto Protocol stipulates the inclusion of these emissions in the assigned amounts of Parties for whom such emissions constituted a net source of greenhouse gases in 1990.

5. The differences existing between the values of table 1, column F and those of table 2, column C are a consequence of a slight difference in the way of calculating the effect of change in methods/data and of rounding, except for Estonia and Finland, for which an error was detected in the corresponding calculations of table 11

in document FCCC/SBSTA/1998/7.

6. Only 13 Parties were selected because they provided complete inventory data in their first national communications for CO2, CH4 and N2O for the years 1991 to 1993/94. Data from the NC1s are used in this paper for analysing methodological problems related to recalculations.

7. For Canada, Denmark, Estonia, Japan, the Netherlands, New Zealand, Norway, Switzerland, the United Kingdom and the United States of America, which provided inventory data until the year 1994 in their first national communications. The period 1991-1994 is considered as a simulated commitment period in this paper. The simulated assigned amounts were calculated using the formula of paragraph 6, but using four years instead of five.

8. France, Germany, Iceland and Japan provided inventory data only until the year 1993 in their first national

communications. Thus, the simulated commitment period and the simulated assigned amounts were calculated for the years 1991 to 1993.

9. The difference between two percentages is expressed in percentage points. The resulting values can be directly compared to the quantified emission limitation or reduction commitments inscribed in Annex B of the

Kyoto Protocol, such as +10 per cent for Iceland and -8 per cent for Switzerland.

10. These values can be directly compared to the quantified emission limitation or reduction commitments inscribed in Annex B of the Kyoto Protocol, such as +10 per cent for Iceland and -8 per cent for Switzerland.