Informing natural climate solutions in the Emerald Edge

About

The western forests of the Pacific Northwest are one of the most productive regions in the United States. Referred to as the Emerald Edge, this region provides beneficial ecosystem services such as water and air purification, habitat areas, and cultural and economic importance to humans. The forests within the Emerald Edge also pose an opportunity for the implementation of natural climate solutions (NCS)—conservation, restoration, and land management actions that increase carbon sequestration or avoid greenhouse gas emissions.

In partnership with The Nature Conservancy, we informed NCS strategies on private forest lands within the Emerald Edge by performing economic analysis to determine the cost-effectiveness of implementing management interventions meant to increase carbon sequestration. 

Approach

The Emerald Edge project quantified the carbon sequestration potential of different forest management strategies, uncovered the costs and benefits associated with these management strategies, and outlined how to tailor these strategies to different stakeholders to inform investment decisions in the region. 

The Bioregional Inventory Originated Simulation Under Management (BioSum) framework served as the analytical foundation for this work. Through literature review and specialist interviews, we identified specific management interventions relevant to the Emerald Edge and parameterized the BIOSUM model to our selected scenarios. These scenarios included extending rotation lengths and incorporating pre-commercial and commercial thinnings. Leveraging the rich Forest Inventory and Analysis (FIA) dataset, a nationwide inventory management system that collects fine scale data at the forest plot level, we applied the BIOSUM model and evaluated (1) the net sequestration of carbon relative to a baseline scenario for different management scenarios, (2) the average management cost per ton of carbon sequestered under each management scenario, and (3) the ownership type and other characteristics for each FIA plot. Using this approach, we were able to explore heterogeneity in results across different stakeholders and identify promising natural climate solutions for land management in the Emerald Edge. 

Key findings

Highlighted in our Climate Change Economics publication, New estimates of the costs of managing forests to increase carbon storage, we found that:

• Carbon storage increases under all management scenarios but with varying levels of cost-effectiveness. By evaluating the effects of alternative rotation lengths and thinning regimes on costs and carbon storage relative to business-as-usual management, we were able to quantify how cost-effectiveness (in terms of $/MT CO2e) varies across these scenarios. 
• The lowest average costs – in the range of $13–18/MT CO2e – are achieved when commercial thinning is combined with longer rotations and discount rates are relatively low. 
• Across the ranges of management scenarios and discount rates we considered, the majority of forest lands in the region can generate carbon offsets at prices below $40/MT CO2e, the current allowance price in California’s carbon market. 
• When carbon flows are valued at the Social Cost of Carbon, benefits from forest management greatly exceed the costs.  
• Overall, forestry-based natural climate solutions have the opportunity to deliver meaningful emissions reductions while supporting landowners and healthy forests along the way.

Partners

This project was a collaboration with The Nature Conservancy.