Quantifying surface albedo and other direct biogeophysical climate forcings of forestry activities: A review.

Authors: Bright RM, K Zhao, RB Jackson, F Cherubini

By altering fluxes of heat, momentum, and moisture exchanges between the land surface and atmosphere, forestry

and other land-use activities affect climate. Although long recognized scientifically as being important, these so-called

biogeophysical forcings are rarely included in climate policies for forestry and other land management projects due

to the many challenges associated with their quantification. Here, we review the scientific literature in the fields of

atmospheric science and terrestrial ecology in light of three main objectives: (i) to elucidate the challenges associated

with quantifying biogeophysical climate forcings connected to land use and land management, with a focus on the

forestry sector; (ii) to identify and describe scientific approaches and/or metrics facilitating the quantification and

interpretation of direct biogeophysical climate forcings; and (iii) to identify and recommend research priorities that

can help overcome the challenges of their attribution to specific land-use activities, bridging the knowledge gap

between the climate modeling, forest ecology, and resource management communities. We find that ignoring surface

biogeophysics may mislead climate mitigation policies, yet existing metrics are unlikely to be sufficient. Successful

metrics ought to (i) include both radiative and nonradiative climate forcings; (ii) reconcile disparities between biogeophysical

and biogeochemical forcings, and (iii) acknowledge trade-offs between global and local climate benefits. We

call for more coordinated research among terrestrial ecologists, resource managers, and coupled climate modelers to

harmonize datasets, refine analytical techniques, and