Presented by Erin Sills (North Carolina State University and CIFOR-ICRAF Senior Associate) at "Bonn Climate Change Conference (SB58) side event: High-integrity forest carbon markets: from global stock-taking to advancing science" on 8 Jun 2023

1. Forest carbon
accounting and
impact evaluation
Erin Sills
North Carolina State University
Center for International Forestry Research

2. monitor forest change and associated emissions to
measure what happens with REDD+
Methods comparison & contrast
Contracting/ accounting
• Compares this measure
to an ex ante forecast of
forest change under
BAU (“crediting
baseline”)
Causal impact evaluation
• Compares this measure
to ex post observation of
forest change in
comparable areas under
BAU (“counterfactual”)
REDD+
Area

3. Methods comparison & contrast
Contracting/ accounting Causal impact evaluation
• Ex ante forecast
establishes a
performance benchmark
• Carbon credits are
generated when
emissions are below the
benchmark or ref. level
• Ex post observation
establishes what would
have happened given
other policy and
economic conditions
• Feedback to investors
and policy-makers

4. Methods comparison & challenge
Contracting/
accounting
Causal impact evaluation
• Ex ante forecast • Ex post observation
X

5. Methods comparison & challenge
Contracting/
accounting
Causal impact evaluation
• Ex ante forecast
Carbon credits
• Ex post observation
Feedback on the
crediting system
X

6. Impact evaluation methods
Comparison
(Control)
REDD+ area
(Intervention)
Before After
IMPACT (BACI)
Forest change
After
Forest change
After
Forest change
Before
Forest change
Before

7. CIFOR Global Comparative Study
• Six countries, 23 sites
• 150 villages inside and outside REDD+ areas,
matched on drivers of forest change
• Before (2010-2011) & after (2013-2014) REDD+
implementation

8. • Based on Hansen Global
Forest Change data
• Performance looks better
when
–Measured at village level
–Based on comparison to
controls
• Careful selection of control
areas reveals the impact of
REDD+
CIFOR Global Comparative Study
Source:
Bos, A. B., Duchelle, A. E., Angelsen, A., Avitabile, V.,
De Sy, V., Herold, M., ... & Wunder, S. (2017).
Comparing methods for assessing the effectiveness
of subnational REDD+ initiatives. Environmental
Research Letters, 12(7), 074007.

9. Comparison
(Control)
REDD+ area
(Intervention)
Before After
IMPACT (BACI)
Forest change
After
Forest change
After
Forest change
Before
Forest change
Before
1) Matching: matched sample with same distribution
of underlying drivers of forest change
2) Synthetic control: weighted combination that
matches underlying drivers of forest change
and trajectory of forest change

10. VCS-certified REDD+ projects established during 2008–
2017 in the Brazilian Amazon forest biome.
Source:
West, T. A., Börner, J., Sills, E. O., &
Kontoleon, A. (2020). Overstated
carbon emission reductions from
voluntary REDD+ projects in the
Brazilian Amazon. Proceedings of the
National Academy of
Sciences, 117(39), 24188-24194.

11. Cumulative post-2000 deforestation REDD+ areas (red)
versus synthetic controls (blue).
(Dashed lines = start dates)

12. Comparison
(Control)
REDD+ area
(Intervention)
Before After
IMPACT (BACI)
Forest change
After
Forest change
After
Forest change
Before
Forest change
Before
1) Matching: matched sample with same distribution
of underlying drivers of forest change
2) Synthetic control: weighted combination that
matches underlying drivers of forest change
and trajectory of forest change

13. Thank you.
sills@ncsu.edu