IPCC Volume 4 · mostly outside the scopes
Land carbon, forests, peat and wood products
Land is the one place where Slate's figures are often negative. Soil and trees store carbon, and changing how land is used releases it. These are stock changes, not activities, and most are reported outside the three scopes.
On this page you'll learn
- How a change in soil carbon becomes an annual figure
- Why removals are kept outside Scope 1
- What each land category covers, and what Tier 1 leaves out
- Reported
- Outside the scopes, except peat extraction (Scope 1)
- Publisher
- IPCC 2006 Vol 4 Ch 2, 4, 5, 6, 7, 8, 9, 12
- Assets
- Land parcels and forest stands, set up in Organisation Setup
Sign convention
Why this matters
A positive change in carbon is carbon gained by the land: a removal. The CO₂ figure is its negative. Reporting a sink as a source is the largest error available here, and its size gives no hint, so tests assert the sign in both directions.
Removals are reported outside the scopes so they can't net against fuel burned. See Scopes 1, 2 and 3.
Soil carbon on cropland and grassland
- SOC_REF
- reference stock, t C/ha, by climate and soil
- F_LU, F_MG, F_I
- land use, management and input factors
- D
- transition period, 20 years by default
A land parcel holds two management states, and the change between them is spread over D. If the actual transition took longer than 20 years, that period is used instead; dividing a 40-year change by 20 would double the annual figure.
- Tillage and input factors don't apply to paddy rice; supplying them is refused.
- The input factor applies only to improved grassland.
- Mineral soil and drained organic soil are separate areas, never one "area" field counted twice.
Forests
Growth minus losses for a forest stand (an asset with an ecological zone and species group). Root biomass uses IPCC's root-to-shoot ratio, which is banded on the standing stock: 0.20 below 125 t/ha, 0.24 above. Harvest losses use Table 4.5's conversion factors, without which a managed forest would report its growth and none of its removals.
Tier 1 leaves out dead wood and litter, and the row says so.
Settlement trees and land conversion
Settlement trees
One year's growth from crown area (Eq 8.2) or from a tree count (Eq 8.3), never both, which would count the same trees twice.
Land converted to settlements or other land
The carbon lost in clearing. IPCC's Chapter 9 publishes no table: its finding is that nothing remains in any pool, and those zeros are stored with the sentences that state them.
Peat extraction and flooded land
Peat extraction (Scope 1)
On-site: hectares drained × a rate. Off-site: all the carbon in the peat dug up and sold, usually the larger part. Every term is a loss, so there's nothing to net, and it's Scope 1 so its N₂O isn't dropped from the totals.
Flooded land
The carbon in vegetation that went under the water (Eq 7.10). The reservoir surface's own CO₂ and methane are in IPCC's Appendix 3, which IPCC says isn't for inventory use; Slate records them as unquantified, not zero.
Harvested wood products
A decay model over the history of wood put into use: a roof truss from 1994 still holds its carbon in 2026. A growing pool is a removal and is reported outside the scopes.