California Air Resources Board

Principal Investigator/Author: Michael Stock

Contractor: Earth Networks, Inc

Contract Number: 18RD033

Project Status: Completed

Relevant CARB Programs: Greenhouse Gas Emission Inventory Program

Topic Areas: Climate Change, AB 32 Climate Change Scoping Plan

Research Summary:

Urbanization has concentrated more than 50% of the global population, at least 70% of fossil-fuel carbon dioxide (CO2) emissions and a significant amount of anthropogenic methane (CH4) along with other important Greenhouse Gases (GHG’s) such as Nitrous Oxide (N2O) and Carbon Monoxide (CO) into a small fraction of the Earth’s land surface. As such, major cities around the world are taking steps to reduce greenhouse gas (GHG) emissions. The potential benefits are large because the combined CO2 emissions of the world’s 50 largest cities are equivalent to the third largest national emitter, trailing only China and the US. To effectively reduce emissions and verify the effectiveness of regulatory programs, accurate accounting is required. In turn, a combination of “bottom-up” emissions inventory estimates with "top-down" methods, which rely on objectively measurable changes in atmospheric composition in and around source regions, is required. Developing a scientifically defensible methodology to Measure, Report, and Verify (MRV) emissions from cities has been highlighted as a critical and necessary action item for the C40 cities organization and within the Carbon Disclosure Project (CDP). 3 The need for scientifically based and internationally recognized measurement strategies and methodologies to effectively diagnose and improve the validity of reported emissions will be amplified and become fundamental to a nation’s capability to demonstrate true MRV compliance.

In coordination with and support from the California Air Resources Board, Earth Networks operated, maintained, and refined baseline greenhouse gas (GHG) monitoring capabilities at three (3) sites in the Los Angeles (LA) Air Basin. These assets are part of a broader network of twelve monitoring sites throughout the LA basin and a project effort called the Los Angeles Megacity (LAM) Carbon Project. The LAM Carbon Project is one of three urban greenhouse gas measurement testbeds established by the National Institutes of Standards and Technology (NIST) to demonstrate scientifically robust greenhouse gas measurement capabilities at urban and regional scales. The initial goal of the effort is to measure multi-year greenhouse gas emission trends from California's South Coast Air Basin generally and by sector, including electricity and industrial power production, transportation, and agriculture. Additional goals include providing a means by which to estimate urban GHG emissions, characterize urban GHG domes, and providing a calibration/validation method for remote sensing measurements. Specific data sets provided via this effort include GHG ambient concentration time series data, calibration data, raw data, and other supporting data.

Keywords: greenhouse gas (GHG), GHG monitoring network, Los Angeles Air Basin, emissions, emission trends, South Coast Air Basin, GHG domes

Final Report: Please email research@arb.ca.gov to request the Final Report generated by this research contract.