Commentary

Op-Eds

Op-Ed in the San Francisco Chronicle, May 15, 2025, We just found millions in waste in California’s cap-and-trade program. Here’s the fix, by Barbara K Haya & Stephen Lezek 

Op-ed in the New York Times, January 4, 2025, Is America Just Going to Abandon Its Towns Falling Into the Ocean?, by Stephen Lezak

Op-Ed in The Conversation, November 1, 2024, US election: Trump is threatening to turn back the tide on America’s environmental laws and reverse climate progress by Stephen Lezak & Barbara K. Haya

Public Comments & Letters 

Integrity Council decision on cookstoves methodologies: an important move towards quality for this important project type, Berkeley Carbon Trading Project Note, published March 20, 2025

Joint Commentary on SBTi’s Discussion Paper: Aligning Corporate Value Chains to Global Climate Goals, specifically on question 13c on the use of Carbon Credits towards company scope 3 targets, submitted to SBTi with coauthors from the University of Utah Wilkes Center for Climate Science and Policy, and University of Oxford's Oxford Net Zero, on October 4, 2024 

Joint Commentary on SBTi’s Discussion Paper: Aligning Corporate Value Chains to Global Climate Goals, specifically on question 13b on the use of Commodity Certificates towards company scope 3 targets, submitted to SBTi with coauthors from the University of Utah Wilkes Center for Climate Science and Policy, and University of Oxford's Oxford Net Zero, on October 4, 2024

Comments on the EU's Technical Assessment on Carbon Removals & Carbon Farming: Forestry, submitted to the European Commission on May 3, 2024

Climate-targets group should rescind its endorsement of carbon offsets, coauthor on Letter to the Editor of Nature. April 30, 2024

Comment on Commodity Futures Trading Commission (CFTC) Guidance Regarding the Listing of Voluntary Carbon Credit Derivative Contracts, RIN 3038–AF40, submitted to the CFTC on February 16, 2024

Comment on Requirements for the development and assessment of Article 6.4 mechanism methodologies and Article 6.4 validation and verification standard for projects, submitted to the UN Article 6.4 Supervisory Body on October 29, 2023

Academic letter in support of AB 1305 and SB 390 (voluntary carbon offsets), submitted to Assembly Member Jesse Gabriel and Senator Monique Limon of the California state legislature on April 17, 2023

Comments to the GHG Protocol on Market-based Accounting Approaches, submitted to the GHG Protocol via their on line survey on March 14, 2023

Comments to the California Air Resources Board on Recommended Changes to its US Forest Projects Offset Protocol, submitted to the California Air Resources Board on December 15, 2022

Comments on the Integrity Council for the Voluntary Offset Market (ICVCM) draft Core Carbon Principles, Assessment Framework, and Assessment Framework, submitted to the ICVCM on September 27, 2022

Comments to the US Securities and Exchange Commission on the proposed offsets provisions under its Proposed Rule on The Enhancement and Standardization of Climate-Related Disclosures for Investors [File No. S7-10-22], submitted to the SEC on June 17, 2022

Comments on the Climate Action Reserve's draft U.S. Landfill Protocol v6.0, submitted to CAR on June 8, 2022

Comments on proposed new VCS methodology - Improved Forest Management through Targeted, Short-Term Harvest Deferral, submitted to Verra on April 22, 2022

Comments on Verra's proposed updates on tonne-year accounting, submitted to Verra on April 8, 2022

Comments on the May 2021 Public Consultation Report of the Taskforce on Scaling Voluntary Carbon Markets (TSVCM), submitted June 21,2021

Public comments submitted on ART TREES 2.0, submitted by Barbara Haya and Matthew D. Potts to Winrock April 2, 2021.

Comments on the Initial Recommendations of the Taskforce on Scaling Voluntary Carbon Markets (TSVCM), submitted to the TSVCM on January 5, 2021.

Comments on ARB’s proposed endorsement of the Tropical Forest Standard: environmental integrity concerns, submitted to the California Air Resources Board on August 29, 2019.

Joint comments on the challenges of monitoring the implementation of California's proposed Tropical Forest Standard, submitted to the California Air Resources Board on August 29, 2019.

Joint comment letter from 110 social and conservation scientists on California’s proposed Tropical Forest Standard (TFS), submitted to the California Air Resources Board on November 14, 2018.

Joint comments submitted to the California Air Resources Board on methods for determining whether offset projects result in Direct Environmental Benefits in the State (DEBS), Submitted July 20, 2018.

Comments submitted to the California Air Resources Board on proposed amendments to the state's cap-and-trade regulation, Submitted May 10, 2018.

Comments submitted to the California Air Resources Board on proposed amendments to the state's cap-and-trade regulation, Submitted Mar. 16, 2018.

Comments submitted to the California Air Resources Board on the state’s draft Climate Change Scoping Plan Update – the proposed strategy for achieving California’s 2030 greenhouse gas target, Submitted Nov. 21, 2016.

Comments submitted to the California Air Resources Board on the state’s proposed REDD program and linkage with Acre, Brazil, Submitted June 4, 2016.

Presentations

Cap and Trade Reauthorization: Offset Program Reform is Necessary, presented by Barbara Haya at the 2025 California Climate Policy Summit in Sacramento, on the panel, Cap and Trade Reauthorization, Reform, and a Revenue Plan.

California’s cap-and-trade and offsets programs – Lessons for Oregon, Presentation to Engineers for a Sustainable Future, co-organized with Center for Sustainable Economy. October 9, 2018. Portland, OR.

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