InVEST Tier 1 Carbon Model
Carbon Storage and Sequestration
• In the Tier 1 model we estimate carbon stock as a
function of land use / land cover.
• Storage indicates the mass of carbon in an
ecosystem at any given point in time.
• Sequestration indicates the change in carbon
storage in an ecosystem over time.
• Valuation is applied to sequestration
Tier 1 Carbon Storage Model
Climate
Atmosphere
Atmosphere
Land use history
Aboveground biomass
Species
Harvested Wood Products
Dead wood
Soil carbon
Soil type, moisture
Microbes, chemistry
Belowground biomass
Land management
Tier 1 Carbon Storage Model
Climate
Atmosphere
Atmosphere
Land use history
Aboveground biomass
Harvested Wood Products
Species
Dead wood
Soil carbon
Land management
Soil type, moisture
Microbes, chemistry
Belowground biomass
5 pools
x
f(cost/ton) =
Value
Sequestration and Value
2008
Δ in C
2058
Net Present Value
Approach to Valuation
Net Present Value is a function of:
• Market discount rate
• Rate of change in the social value of carbon
• Social or market cost of carbon
Carbon model is most appropriate for valuing the
Social cost of carbon: The price of current and
future damage caused by releasing a ton of
carbon into the atmosphere
Input Data
Required data:
A land use / land cover (LULC) map
Table of carbon pools
(metric tons / hectare)
Input Data
Optional data:
• For calcuating C stored in harvested wood produtcs:
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–
–
–
–
Map of timber harvest land parcels with data on
frequency of harvest
annual harvest amount
decay rate of wood products
density / volume factors
• Future land use map
• Economic data (carbon value / price, discount rate)
Carbon Pool Data
• Local plot studies
• Published analyses on similar regions
• IPCC tables
Output
• Map of current carbon storage
(Mg/cell)
• Map of future carbon storage
- If future land use provided
• Carbon sequestration map
= (future - present carbon storage)
• Map of economic value of carbon
sequestered
Strengths
• Simple, requires relatively little data, thus also
works for data-sparse regions
• Both biophysical (carbon storage / sequestration)
and economic valuation modeling possible
Limitations
• Simplified carbon cycle
• Economic valuation assumes a
linear trend in sequestration
over time
• Output is only as detailed and reliable as the land use
classes and carbon pool data that are input.
• Carbon sequestration does not occur in an area unless
the area’s land use changes over time or wood is
harvested.
Storage in Biomass
Land cover transitions
Forest
Reality
T1
T2
Forest
(old)
Model
Forest
(young)
T1
T2
Application
• Land use planners: Compare
consequences of future scenarios
• Ecosystem service tradeoffs
• Carbon market: First-pass
analysis
• Not appropriate for precise costbenefit analysis etc
Gains and losses in carbon
stocks from 2008 to 2058 in
Sumatra, Indonesia
Carbon
gain
Carbon
loss
2008
2058
Dharmasraya district, Sumatra, Indonesia
Carbon gains and losses under alternative scenarios
Gain
Loss
2008 to Green Vision
2008 to Business as Usual Plan
Priority districts for investing in forest carbon projects
High priority districts have:
-High deforestation risk
- Large biomass carbon stocks
- Relatively lower agricultural value