4.7.3. Additional Technical Considerations for Implementing Article 3.4
If a real reduction in radiative forcing is to be achieved through land use-related
activities, the Parties will need to address the following technical considerations:
- Either the land area on which changes in carbon stocks are to be
monitored-and the pools to be measured-must be defined exactly and spatially
explicitly, or the major management practices leading to carbon storage must
be defined in terms that are verifiable and correlated with net changes in
the flux of GHGs resulting from their application. The change in carbon stocks
approach is applicable only to carbon dioxide (which is the dominant land
use-related GHG at a global level), whereas the activity-based approach applies
to all gases. Note that both approaches will probably make use of models,
and both apply to specific land areas. The land-based and activity-based approaches
are not mutually exclusive; they could be applied simultaneously. This consideration
allows for an internal check and is analogous to the simultaneous use of the
"top-down" and "bottom-up" accounting procedures for fossil fuels.
- Direct measurements of changes in GHG fluxes resulting from changes in land-use
practices currently (and for the first commitment period) are not feasible
on an operational basis at the national scale. Therefore, estimation of fluxes
based on activities requires the use of models. Very simple models (such as
default emission factor per hectare) do not capture the range of variation
that typically occurs in land use-related activities. Models require more
information than simply the degree of implementation of the practice to have
acceptable accuracy; they may need to incorporate information about the environment
in which the practice is applied, the land-use history, the timing of actions
within the practice, and the intensity with which it is applied. The details
vary from practice to practice.
- If the land-based approach is followed and the area thus defined
is less than the total land area of each country reporting stock changes for
purposes of adjustment of Kyoto Protocol targets, or if activities are defined
that are substantively less than the full range of activities that are applied
to a given land use, then there is a significant risk of displacement
of the putative gains to other areas (leakage) or their erosion by other activities.
Such effects may not be preventable, but they could be accounted. Effectively,
this accounting would require attention to full and symmetrical accounting
of land area or activities, or both.
- If the land-based approach is used, the reporting interval for changes
in carbon stocks probably should not be less than about 5 years because changes
over shorter periods will be difficult to detect reliably in many pools. There
is no theoretical upper limit to the period, but the Parties may need to consider
some practical upper limit for managing the global atmosphere via the international
- Reporting intervals for carbon stock changes that result from Article 3.4
activities may need to be contiguous for the accounting to remain accurate
because some of the carbon pools are sufficiently volatile that substantial
losses to the atmosphere could occur within a period of a few years.
- The pools to which stock-change calculations are to be applied must be
defined consistently over time and space, and full accounting requires that
all pools that are substantially affected by the land use and land-use change
activities be counted.
- Adjustments to commitments that are based on Article 3.4 activities should
include the effects of all major GHGs (CO2, CH4, and N2O) because in many
cases the net effect is strongly affected by two or more gases. In some cases,
non-GHG climate impacts (such as changes in albedo) also may need to be considered.
Where other GHGs are already accounted for in the inventory (for example,
methane emissions from rice paddies), care will be needed to avoid double-counting.
- Failure to distinguish between changes in land-based GHG fluxes that are
a direct consequence of human-induced land-use activities and those that result
from natural processes or indirectly from human activities (e.g., from CO2
fertilization or deposition of atmospheric nitrogen) could allow Parties to
claim a large portion of the current terrestrial carbon sink as an adjustment
to the Kyoto targets. Measuring which portion of the change in fluxes is directly
human induced is not technically feasible, but inferring this fraction is
possible, by using models, agreed baselines, or control areas.