Introduction
The Second State of the Carbon Cycle Report (SOCCR2) is an assessment that examines the U.S. and North American carbon cycle processes, stocks, fluxes, and interactions with global-scale carbon budgets. It encompasses consideration of carbon dynamics in soils, water (including freshwater and near-coastal oceans), vegetation, aquatic-terrestrial interfaces (e.g., coasts, estuaries, wetlands), human settlements, agriculture, and forestry. The first SOCCR assessment was released in 2007, and this second assessment examines the progress in scientific understanding that has been made in the decade since then. While SOCCR2 does not prescribe or recommend policy, the draft report states that “it is intended to help inform mitigation and adaptation policies and management decisions related to the carbon cycle, supporting improved coordination for pertinent research, and monitoring and management activities for responding to global change”.
SOCCR2 is one component of a broader suite of work carried out under the umbrella of the Fourth National Climate Assessment (NCA4). This assessment was led by the U.S. Global Change Research Program’s (USGCRP) Carbon Cycle Interagency Working Group (CCIWG). The development of SOCCR2 was guided by a Federal Steering Committee composed of senior federal scientists, and was built upon the contributions of over 200 lead and contributing authors.
To help assure the quality and rigor of this assessment, the National Academies of Sciences, Engineering, and Medicine (NASEM) was asked to convene a Committee to carry out an independent peer review of the draft document, concurrent with the open public review period. The Committee comprises 12 people with a variety of expertise related to issues discussed in SOCCR2. The Committee was given the following official Statement of Task.
The Committee will conduct an independent review of the SOCCR2 report. The review will provide an overall critique of the report and address the following questions:
- Are the goals, objectives and intended audience of the product clearly described in the document? Does the report meet its stated goals?
- Does the report accurately reflect the scientific literature? Are there any critical content areas missing from the report?
- Are the findings documented in a consistent, transparent and credible way?
- Are the report’s key messages and graphics clear and appropriate? Specifically, do they reflect supporting evidence, include an assessment of likelihood, and communicate effectively?
- Are the research needs identified in the report appropriate?
- Are the data and analyses handled in a competent manner? Are statistical methods applied appropriately?
- Are the document’s presentation, level of technicality, and organization effective?
- What other significant improvements, if any, might be made in the document?
To address this charge, committee members were assigned to small teams to focus on evaluating individual chapters within the draft SOCCR2 report, while everyone examined the Executive Summary and the draft report’s key messages. The Committee held one in-person meeting in late November 2017, where members discussed the draft report in closed session, and also spoke with several of the SOCCR2 authors (to ask clarifying questions) in open session. This document provides the
Committee’s review, including their consensus views on the draft report overall (organized primarily around the Statement of Task questions); and it includes a compilation of all the chapter-specific comments—which also focused (where feasible) on the Statement of Task questions, and which ranged from major substantive concerns to minor editorial suggestions.
While the Committee does offer numerous suggestions for improving various parts of the draft report, these are offered in the spirit of constructive criticism, with great admiration for and appreciation of the huge amount of work that the SOCCR2 authors have put into this assessment, and with shared hopes that the final report will provide a valuable resource for decision makers, scientists, and many others across the country.