To resolve this question, in 2030 I will look at publicly-available grantmaking documentation (like this Openphil website, for example), adding up all the grants between October 2023 and January 2030 that support climate geoengineering, and resolve YES if the grand total exceeds ten million US dollars.
Any kind of geoengineering (including everything mentioned on that wikipedia page) counts, including relatively mundane solutions like reforestation or convincing people to paint their roofs white. It is also fine if the money goes towards advocacy for geoengineering rather than direct implementation of a project.
"EA funders" means places like OpenPhil, LTFF, SFF, Longview Philanthropy, Founders Fund, GiveWell, ACX Grants, etc. Some example "EA-adjacent" funding sources that wouldn't count, even if their money goes directly to this cause area: Patrick Collison, Yuri Milner, the Bill & Melinda Gates Foundation, Elon Musk, Vitalik Buterin, Peter Thiel. This is obviously a fuzzy distinction (what if one of the aforementioned billionares becomes noticeably more EA-influenced by 2030? etc), but I'll try my best to resolve the question in the spirit of reflecting how the EA community has grown over time.
For markets about other cause-area-candidates (like wild-animal welfare and civilizational-refuge bunkers!), check out the "New EA Cause Area?" tag!