California Governor Brown signed a Memorandum of Understanding with environmental officials in Mexico, the world's 11th largest emitter of greenhouse gases, which aims to reduce emissions and facilitate the development of carbon pricing systems.

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"The agreement, which came on the first full day of Brown’s trade and investment mission to Mexico, also called for collaboration on fire emergency response along the shared 136-mile border, improving air quality, and strengthening fuel efficiency in vehicles, including trucks carrying freight."

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