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SanDiego350 is building a movement to prevent the worst impacts of climate change and climate injustice through education and outreach, public policy advocacy, and mobilizing people to take action.


Our vision is for an informed, mobilized and united community that is empowered to reduce our carbon footprint, and hold our elected officials accountable for creating a low-carbon, sustainable and just world. Our power comes from our alliance with social justice, environmental, labor, health, faith and other partners.

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Governments and corporations will not take the necessary action to reduce the impact of climate change and climate injustice on their own due to the entrenched economic and political status quo of fossil fuel  dependence, corporate power, and economic, racial and other injustices.
An organized mass movement rooted in people power is needed to build up social and political pressure for change by galvanizing public support, countering the power of vested interests, and showing that alternative pathways to a thriving global community are possible, desirable and needed. Escalated pressure – coordinated across our networks – is required to achieve change in the rapidly shrinking window for effective action. 
Our efforts – education and outreach, public policy advocacy, coalition building, and mobilizing people to take action – strive not just to reduce GHG emissions, but to build political power with allies to create the better world we know is possible – together.


In September 2011 we brought together hundreds of San Diego County residents, and we collectively called on our elected representatives to take immediate, strong action on climate change as part of’s international day of action on climate change. After that event, we decided to form a group and started organizing San Diegans to take action on climate change. In 2014 we became a 501(c)(3) nonprofit organization and in 2016 we brought on our first staff person. We’ve organized San Diego’s largest climate mobilizations, including the 5,500-person “People’s Climate March” in April 2017 and the climate walkouts in 2019.

WHY 350?

As a group focused on mitigating the impacts of climate change and injustices,’s name originates from 350 parts per million (ppm), the scientifically determined safe upper limit of carbon dioxide (CO2) in our atmosphere.
For millions of years leading up to the industrial revolution, our atmosphere averaged roughly 270ppm of CO2. As humans began burning coal, oil, and gas, and the use of fossil fuels skyrocketed, so did atmospheric levels of CO2. Our atmosphere currently holds over 417ppm of CO2, with an increasing trend of about 2 additional ppm units per year.
To protect the biosphere, local and global communities, younger generations, and the future of our planet, we must eliminate greenhouse gas emissions and reduce CO2 levels to below the 350ppm safety threshold as quickly as possible. was founded by a group of university friends, including Bill McKibben, in 2008, with the goal of building a global climate movement. McKibben wrote one of the first books on global warming for the general public.
SanDiego350 is an affiliate of, but we are a completely separate organization. Although founded on the same principals and guiding practices, we make our own decisions, set our own campaign priorities, and do our own fundraising. We attribute our success to our hundreds of dedicated volunteers who make up more than 15 volunteer teams, our donors, and the rest of our SanDiego350 community.
C02 6 year graph
CO2 levels continue to rise well above the target of 350 ppm last observed in 1988.
(Image source: National Oceanic and Atmospheric Administration)

SanDiego350 volunteers helped to create this website. Thank you to Jenna Asperslag for the website design and to Zoe Duerksen-Salm and Bob Silvern for the web development.