Many of these impressive sub-national and non-state climate action initiatives will take their next steps forward at the Global Climate Action Summit in 12-14 San Francisco September, hosted by California Governor Jerry Brown. These include the Under2 Coalition, a group of over 200 city and provincial governments around the world which are committed to reducing their greenhouse gas emissions toward net zero by 2050, and the US Climate Alliance, a group of 17 states and territories whose combined economic output is larger than that of all but two countries, which have committed to delivering their share of the US government’s Paris commitment.

As for business, through the Science-Based Targets initiative, 126 companies around the world have set an emission target that is in line with the level of decarbonization required to keep the global temperature increase below 2°C, and a further 333 have committed to follow through as well.

One-hundred and thirty-nine companies have committed to 100% renewable power consumption through the RE100 initiative. Seventy-eight companies have committed to use an internal carbon price to guide their investment strategies, and 165 companies have committed to disclose their carbon-related performance and strategy in their annual reports and financial statements to shareholders. All of these corporate initiatives and others are supported by the We Mean Business Coalition of seven international environmental and business organizations.

Adding fresh momentum

The summit in San Francisco is an important innovation in international climate cooperation and hence international relations. By creating a public-private platform to showcase contributions made by such first-mover sub-national governments and private sector institutions, it is helping to bring them to scale worldwide and thereby add fresh momentum to humanity’s race against time.

We need to build on the “can do” spirit of San Francisco and create a mechanism to scale across the world the determination and self-initiative that so many city, provincial, business and civil society leaders have come to San Francisco to display. National governments can help.

Heads of government gathering in New York later this month for the annual UN General Assembly summit should direct their ministers to agree on a declaration at the next “COP24” round of climate talks in Poland in November that invites any interested city or provincial government to develop its own “Sub-Nationally Determined Contribution” (SNDC). Companies and other civil society institution such as a universities, religious organizations and NGOs should be invited to do the same in an “Institutionally Determined Contribution” (IDC). Unlike the official United Nations Nationally Determined Contributions (NDCs), such sub-national and institutional commitments should not be subject to the monitoring and review mechanisms of the Paris accord. Rather, they should remain an informal mechanism for enabling the broader social mobilization that clearly will be required to place the planet on track toward the 2-degree goal.

Such a universal framework to enable distributed action across society could generate a snowball of political, industry and citizen peer pressure and benchmarking. This could eventually establish the practice of setting of climate targets and strategies to achieve them as a new 21st century norm of corporate, investor, municipal and non-profit governance – a common rather than best practice.

Climate advocacy could use a boost these days. A practical mechanism like this with the potential to scale at the grass roots level globally could provide it, especially if it were linked in symbol and spirit to the official intergovernmental effort in the United Nations. It could be an important legacy of the path-breaking international gathering taking place in San Francisco this week.