Table 1 Variable definitions for the IPCC/EPA production accounting approach shown in Figure 2 [3]. Units for all variables are MgC yr^-1.

ΔS

Annual carbon stock change for the total forest sector, which is calculated as ΔS = (NEE-H)+(ΔC _R1 ) in the production accounting approach.

NEE

Annual net ecosystem carbon exchange, the annual net carbon that moves from the atmosphere to forests.

H

Annual harvest of wood for products, which includes wood and residues removed from harvest sites, but excludes resides left at harvest sites.

HWP

Harvested wood products in use or at solid waste disposal sites.

E_R1

Annual emission of carbon to the atmosphere in the Northern Region from products made from wood harvested in the Northern Region.

E_IM

Annual emission of carbon to the atmosphere in the Northern Region from products made from wood harvested outside of the Northern Region and imported into The Northern Region.

P_EX

Annual exports of wood and paper products out of the Northern Region, including roundwood, chips, residue, pulp and recovered (recycled) products.

P_IM

Annual imports of wood and paper products into the Northern Region, including roundwood, chips, residue, pulp and recovered (recycled) products.

E_{EX R1}

Annual emission of carbon to the atmosphere in areas outside of the Northern Region from products made from wood harvested in the Northern Region.

E_OTHER

Annual emission of carbon to the atmosphere in areas outside of the Northern Region from products made from wood harvested outside the Northern Region.

C_R1

Stock of harvested wood products carbon in use or at solid waste disposal sites where products used wood from the Northern Region harvests.

ΔC_{IU R1}

Annual change in carbon stored in harvested wood products in products in use where products used wood from the Northern Region harvests.

ΔC_{SWDS R1}

Annual change in carbon stored in harvested wood products at solid waste disposal sites where products used wood from the Northern Region harvests.

ΔC_R1

Annual change in carbon stored in harvested wood products in products in use and at solid waste disposal sites where products used wood from the Northern Region harvests.

ΔC_R1 = ΔC_{IU R1} + ΔC_{SWDS R1}