USDA Forest Service

Pacific Southwest Research Station

Pacific Southwest
Research Station

800 Buchanan Street
Albany, CA 94710-0011
(510) 883-8830
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Urban Forests and Climate Change: Greenhouse Gas Reporting ProtocolA tree-lined street with a shaded house

The Urban Forest Greenhouse Gas Reporting Protocol has been approved!! After more than 18 months of work, eleven drafts, countless meetings, and extremely helpful feedback from our stakeholder groups, the California Climate Action Registry's Board of Directors approved the Protocol on August 12.

You can find the final version of the Protocol here [PDF1.2MB].

For the latest information from the California Registry, visit their website. There you can register to report your own or your organization's emissions, begin an urban forest greenhouse gas reduction project, view other entities' emission reports, and keep up with the latest in global warming news.

Let the projects begin!!



Global climate change and trees

Carbon dioxide levels in the atmosphere are higher than at any time in the last 400,000 years according to the most recent report of the International Panel on Climate Change, and the rate at which they are being added is increasing. Humans add carbon dioxide and other greenhouse gases (GHG) to the atmosphere through a number of activities, in particular the burning of coal, gasoline, and other fuels for energy.

The problem of GHG is twofold. First, how do we reduce the amount of GHG being produced? Second, how do we lower the excessive amounts already in the atmosphere?

Urban forests are one solution to both.

Trees in cities affect GHG in three main ways:

  1. As they grow, they remove carbon dioxide and other GHG from the atmosphere and sequester them in their leaves, branches, trunks and roots; when the trees die, however, the carbon is released back into the air through decomposition.

  2. By shading buildings in summer and blocking cold winter winds, trees reduce electricity and natural gas use, which reduces the production of GHG at the power plant or home furnace.

  3. Wood from dead trees can be used to produce energy, create biofuel, and for thermal heat and cooling, replacing fuels that produce more GHG.

Have you heard talk in the media recently questioning the value of trees in fighting climate change?

Read our take on the subject in "Urban Tree Planting and Greenhouse Gas Reductions" in the June issue of Arborist News or Greg McPherson's op-ed in the Los Angeles Times, "Leafy, green and good."

Putting our research to use...

Our Team has been working for years to quantify the contribution of trees to reducing global warming. We have extensive data on tree growth and GHG sequestration for trees throughout California, and we have developed models to estimate the effects of shade trees on energy use. For these reasons, we have been invited to lead a team in drafting Urban Forest Reporting Protocols for the California Climate Action Registry.

The Registry

We can't begin reducing GHG emissions without understanding the current situation. The Registry is the first in the nation to provide a forum for entities—corporations, municipalities, even individuals—to voluntarily report greenhouse gas (GHG) emissions. In this way, the nonprofit partnership hopes to encourage early actions to reduce emissions.

A series of protocols, including one for general reporting and other industry-specific protocols, provide guidance on how to report your organization's emissions or emission reductions in a way that is complete, transparent, and accurate. It's important to note that the Registry is only an accounting forum, a place to document and monitor emissions levels. It is not involved in a cap-and-trade market, in offering carbon offsets, or in setting a carbon tax. These policy-related decisions will be made later at the legislative level.

Developing the Urban Forest Protocols: a team effort

For the past two years, the we led a team in drafting the Urban Forest Reporting Protocol under the direction of a steering committee, including representatives from Cal Fire, Pacific Forest Trust, the Registry, California Energy Commission, California Air Resources Board and utility, nonprofit and urban forestry professionals. Our work has been guided by a technical advisory committee made up of researchers, policy makers, and public officials, and by a stakeholder committee representing groups most likely to make use of the protocols.

The drafting process began with an outline, which was reviewed by the steering, technical advisory, and stakeholder committees. The final version of the outline was released at the end of June 2007. We spent the remainder of 2007 transforming the outline into a complete draft version of the protocols, which was reviewed by all three committees again. Their comments were incorporated and a final draft version was presented to the Registry in June 2008.

On August 12, 2008, the final version of the Urban Forest Protocol was unanimously approved by the California Registry's Board of Directors.


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Last Modified: May 16, 2011 07:58:35 PM