Which private donors and universities have funded outdoor geoengineering experiments and what transparency rules govern those projects?
Executive summary
Outdoor solar geoengineering experiments to date have been financed by a mix of university internal funds, philanthropic contributions channeled through university programs, venture-backed startups, and a handful of government initiatives; notable names include Harvard’s Solar Geoengineering Research Program (internal Harvard funds and outside contributors), the company Make Sunsets, and Israeli startup Stardust (Harvard: [3]; Keutsch Group/SCoPEx: [4]; Make Sunsets/Stardust: [1], p1_s2). Transparency requirements remain largely voluntary and uneven: scientific societies and recent policy briefs demand full disclosure of funding and independent review, while statutory oversight is patchy and national governments have only recently begun creating formal programs and rules (AGU ethics, PNAS recommendations, NOAA/Congress actions: [5]; [1]; p1_s5).
1. Who has put money on the table: universities and internal research funds
Harvard’s canceled SCoPEx project is the clearest university-linked example: hardware and operations were funded from internal Harvard research funds provided to the investigators, supplemented by a list of outside contributors to a fund controlled by Harvard’s Solar Geoengineering Research Program (SGRP) that the university publicly acknowledged and committed to review (Harvard/SCoPEx: [4]; funding description: [1]2). Other academic groups have sought public funds or federal partnerships—University of Washington pursued NOAA or DOE support and hoped to access government ships and planes for larger marine cloud-brightening work, indicating universities often blend internal, philanthropic, and prospective federal resources (UW/NOAA: p1_s8).
2. Private companies and philanthropic donors: commercial actors and venture capital
Private-sector actors have been active and visible: Make Sunsets has released sulfur-laden balloons and marketed “cooling credits,” and Stardust attracted roughly $15 million in venture capital—all cited by recent reviews as emblematic of private funding pushing experiments and commercialization outside traditional academic channels (Make Sunsets/Stardust: [1]; p1_s2). Reporting from environmental groups and watchdogs flags a mix of philanthropic donations routed through donor-advised funds (DAFs) and direct private contributions into research programs—practices PNAS authors say should be disclosed down to original donors where possible because they currently obscure accountability [1] [2].
3. Government funding and programmatic shifts
Governments are only recently stepping into the funding and oversight void: the U.S. Congress earmarked at least $4 million for NOAA to study climate interventions and assess experiments, and the UK has launched multi-million-pound programs (including Aria) funding controlled small-scale outdoor work, signaling a shift toward public sponsorship that carries distinct transparency expectations versus purely private experiments (Congress/NOAA $4M: [6]; UK Aria program: [1]1).
4. Transparency rules, codes, and institutional reviews
Scientific bodies and university advisory committees have developed de facto rules: the American Geophysical Union’s ethical framework calls for “complete transparency of funding and decision-making” and separation between funders and research decisions, while PNAS authors and Science commentators recommend minimum requirements such as publicly disclosing all funding sources, amounts, and DAF origins and applying review standards comparable to publicly funded research (AGU: [5]; PNAS recommendations: [1]; Science governance analysis: p1_s4). Harvard’s external Advisory Committee for SCoPEx produced one of the most detailed applied governance frameworks, covering safety, conflicts of interest, legal compliance, and societal engagement—an example institutions have cited as a model (Harvard AC framework: p1_s4).
5. Gaps, conflicts, and contested transparency
Despite emerging norms, there is no globally binding regime: authors warn that most governments have deliberately declined to coordinate funding or regulation, producing an “opposite” of transparency where private actors can operate with limited oversight, and environmental groups note domestic statutes like the U.S. Weather Modification Reporting Act are not being applied to modern geoengineering projects (governance vacuum: [1]; [7]; reporting/Weather Modification Act: [1]4). Critics also flag commercial motives—selling “cooling credits” or positioning startups for market advantage—as potential hidden agendas that transparency rules aim to curb but currently do not uniformly constrain (Make Sunsets commercialization critique: [1]; p1_s4).
6. Bottom line: who and under what rules
Universities such as Harvard have funded or housed the most scrutinized outdoor experiment proposals using internal funds plus outside contributors, private startups with venture or philanthropic backing have undertaken or promoted real-world releases (Make Sunsets, Stardust), and governments are only beginning to formalize public funding and oversight (Harvard/SGRP, Make Sunsets/Stardust, NOAA/UK programs: [3]; [1]; [6]; [1]1). Transparency rules today are dominated by voluntary frameworks—AGU ethics, PNAS minimums, university advisory committees and calls for financial disclosure and independent review—but statutory and international governance remain incomplete, leaving significant gaps between norms and practice (AGU/PNAS/Science recommendations: [5]; [1]; [8]; governance concerns: p1_s9).