State of the Carbon Cycle Report (SOCCR)

2nd State of the Carbon Cycle Report (SOCCR-2)


Relevant Resources

SOCCR-2 Public Engagement and Outreach

SOCCR (2007)


2nd State of the Carbon Cycle Report (SOCCR-2)


In 2015, the Carbon Cycle Interagency Working Group (CCIWG), via the U.S. Carbon Cycle Science Program, initiated plans for the 2nd State of the Carbon Cycle Report (SOCCR-2) as a follow-up to the 1st SOCCR (2007) which was a Special Assessment Product (SAP 2.2) of USGCRP’s 2nd National Climate Assessment (NCA), and as a product of the Sustained National Climate Assessment. Led by the CCIWG, under USCGRP auspices and with USDA as the administrative lead, this federal interagency report is currently in development and estimated to be published in late 2017/early 2018.

The focus of SOCCR-2 is on the scientific understanding of U.S. and North American carbon cycle stocks and fluxes, in the context of and interactions with global scale budgets and climate change impacts in managed and unmanaged systems.  Carbon stocks and fluxes in soils, water (including oceans), vegetation, aquatic-terrestrial interfaces (coastal/ estuaries/ wetlands), human settlements, agriculture, forestry etc. are included.

Relevant carbon management science perspectives and support tools for supporting decisions, as addressed in and related to the US Carbon Cycle Science Plan (2011) and U.S. National Climate Assessment, USGCRP 2012-2021 Strategic Plan and Global Change Research Act (GCRA) of 1990 will are included in this assessment.  In addition to identifying uncertainties, rising opportunities for improving measurements and projections in the carbon cycle are be identified.

Relevant Resources

First Federal Register Notice (February 12, 2016)

30-day Federal Register Notice (FRN) (released on February 12, 2016) by USDA-NIFA, on behalf of the CCIWG and USGCRP, is available here.

The PDF of the FRN is available here. The deadline for submission of nominations for contributors, technical input and comments on the draft prospectus was March 14, 2016.

Prospectus (incl . draft Table of Contents)

Presentation slides from AGU 2016 (for info on report development process and leadership team composition)

Chapter Leads and list of report contributors, including chapter leads (as of January 2017)

All authors by chapters (as of March 23, 2017)

SOCCR-2 Public Engagement and Outreach

In addition to the above section, details on prior CCIWG-led SOCCR-2 public engagement and outreach events and related opportunities can be accessed via the chronological list of public announcements below.

Please check, subscribe to @USCarbon and/or subscribe to Carbon News for updates.

January, 2017

A new ad hoc committee of the Academies will conduct an independent review of the SOCCR-2 draft report, which will be available in early 2017....

December, 2016

Grants, opportunities and SOCCR-2 sessions and town halls in San Francisco in December 2016.....

June, 2016

The 2nd State of the Carbon Cycle Report (SOCCR-2): Assessing the Last Decades' Science of the Carbon Cycle across North America and Adjacent Oceans

February, 2016

Submit author nominations, technical input and comments on the draft prospectus.....

January, 2016

This 1-day public forum will present an opportunity for interested parties and stakeholders to provide individual input on proposed SOCCR-2 themes.

December, 2015

December 2015 AGU San Francisco sessions, February 2016 Washington DC Public Forum.....

October, 2015

... opportunities for the greater geophysical community to learn about and provide feedback on the 2nd State of the Carbon Cycle Report (SOCCR-2) that we are in the process of planning...

August, 2015

Participants learned about the USGCRP annual research prioritization process as well as partnerships and opportunities....

The US Carbon Cycle Science Program is organizing a special session 'Carbon Cycle Science at the Frontier of Global Change: A Coordinated Effort Among Federal Agencies'.....

June, 2015

Abstracts informing and related to this Special Scientific Assessment of the Current Status and Opportunities in carbon cycle science across terrestrial, atmospheric and oceanic systems are requested....

May, 2015

The CCIWG will meet with the CCSSG for individual input on carbon cycle science needs and opportunities......



Some background documents related to the earlier SOCCR, released in 2007, are available below.

State of the Carbon Cycle Report (SOCCR-1, published in 2007)

Color photo of front cover with white text on orange background and other photos

The carbon cycle chapter of the Strategic Plan for the U.S. Climate Change Science Program describes a vision to publish a series of government products on the status and trends of carbon emission and sequestration. The first of these reports, the State of the Carbon Cycle Report (SOCCR), was released by the US Climate Change Science Program (now the USGCRP) on November 13, 2007.

The 2003 Terms of Reference for the first SOCCR (2007), prepared by the Carbon Cycle Interagency Working Group and in consultation with the Carbon Cycle Scientific Steering Group, envisioned a report designed to provide accurate, unbiased, and policy-relevant scientific information concerning the carbon cycle to a broad range of stakeholders. The SOCCR Coordinating Team focused on (1) summarizing our knowledge of carbon cycle properties and changes relevant to the contributions of and impacts upon the U.S. and the rest of the world, and (2) providing scientific information for U.S. decision support focused on key issues for carbon management and policy. The report depends on results from comprehensive and informative programs, such as the North American Carbon Program and Ocean Carbon and Climate Change Program, and demands a global perspective, integrating information from studies on land and in the atmosphere and oceans around the world. The expected audience includes researchers, decision makers in the public and private sectors and the public. The Executive Summary is available here.


Background documents, prospectus, prior draft versions, review comments and responses from the first SOCCR (2007) are available here and below  (source:

SOCCR logo

Draft Versions of the SOCCR (2007) Report

March 2007 version of SOCCR/SAP 2.2, March 2007 revision of government review draft

Executive Summary

Entire Document

January 2007 version of SOCCR/SAP 2.2, government review draft

Executive Summary

Entire Document

September 2006 version of SOCCR/SAP 2.2, CCSP public review draft

Executive Summary

Entire Document

May 2006 version of SOCCR/SAP 2.2, submitted for technical/peer review

Entire Document

Review Comments and Responses

Public Review Commments and Authors' Responses

Technical Peer Review Commments and Authors' Responses


Draft Prospectus for Synthesis and Assessment Product (SAP) 2.2 (March 7, 2005)


Final Outline

The SOCCR Outline (as of November, 2004)

View the Responses to Comments Received on Outline through December 2005

Background Documents

About the SOCCR process

What is the Carbon Cycle?

This page last updated 03/23/2017 - 15:07