"All UN member states—with the exception of the United States—have ratified the treaty"
https://en.wikipedia.org/wiki/Convention_on_Biological_Diversity

This means that the legitimization of the international representation through this UN body is overwhelming.


Treaty text: Convention on biological diversity
https://www.cbd.int/doc/legal/cbd-en.pdf


"(...)
1.1 MANDATE
At the tenth meeting of the Conference of the Parties (COP-10) to the Convention on Biological Diversity (CBD), Parties adopted a decision on climate-related geoengineering (2) and its impacts on the achievement of the objectives of the CBD as part of its decision on biodiversity and climate change.

Specifically, in paragraph 8 of decision X/33, the Conference of the Parties:
Invite[d] Parties and other Governments, according to national circumstances and priorities, as well as relevant organizations and processes, to consider the guidance below on ways to conserve, sustainably use and restore biodiversity and ecosystem services while contributing to climate change mitigation and adaptation to (….)

(w) Ensure, in line and consistent with decision IX/16 C, on ocean fertilization and biodiversity and climate change, in the absence of science based, global, transparent and effective control and regulatory mechanisms for geo-engineering, and in accordance with the precautionary approach and Article 14 of the Convention, that no climate-related geo-engineering activities(3) that may affect biodiversity take place, until there is an adequate scientific basis on which to justify such activities and appropriate consideration of the associated risks for the environment and biodiversity and associated social, economic and cultural impacts, with the exception of small scale scientific research studies that would be conducted in a controlled setting in accordance with Article 3 of the Convention, and only if they are justified by the need to gather specific scientific data and are subject to a thorough prior assessment of the potential impacts on the environment;

(x) Make sure that ocean fertilization activities are addressed in accordance with decision IX/16 C, acknowledging the work of the London Convention/London Protocol.”

Further, in paragraph 9 of the same decision, the Conference of the Parties:

Request[ed] the Executive Secretary to:
(l) Compile and synthesize available scientific information, and views and experiences of indigenous and local communities and other stakeholders, on the possible impacts of geo-engineering techniques on biodiversity and associated social, economic and cultural considerations, and options on definitions and understandings of climate-related geo-engineering relevant to the Convention on Biological Diversity and make it available for consideration at a meeting of the Subsidiary Body on Scientific, Technical and Technological Advice (SBSTTA) prior to the eleventh meeting of the Conference of the Parties; and

(m) Taking into account the possible need for science based global, transparent and effective control and regulatory mechanisms, subject to the availability of financial resources, undertake a study on gaps in such existing mechanisms for climate-related geo-engineering relevant to the Convention on Biological Diversity, bearing in mind that such mechanisms may not be best placed under the Convention on Biological Diversity, for consideration by SBSTTA prior to a future meeting of the Conference of the Parties and to communicate the results to relevant organizations."
CBD Technical Series No. 66
Geoengineering in Relation to the
Convention on Biological Diversity:
Technical and Regulatory Matters
Part I.
Impacts of Climate-Related
Geoengineering on Biological Diversity
September 2012
https://www.cbd.int/doc/publications/cbd-ts-66-en.pdf page 15

"Accordingly, this report has been prepared by a group of experts(4) and the CBD Secretariat following discussions of a liaison group convened thanks to financial support from the Government of the United Kingdom of Great Britain and Northern Ireland, and the Government of Norway. The report compiles and synthesizes available scientific information on the possible impacts of geoengineering techniques on biodiversity, including preliminary information on associated social, economic and cultural considerations. Related legal and regulatory matters are treated in a separate study (see Part II of this volume). In addition, a complementary consultation process was carried out by the CBD to seek the views of indigenous and local communities on the possible impacts of geoengineering techniques on biodiversity and associated social, economic and cultural considerations.

The study on the impacts of climate-related geoengineering on biodiversity and on the regulatory framework for geoengineering were presented to the sixteenth meeting of the Subsidiary Body on Scientific, Technical and Technological Advice (in documents UNEP/CBD/SBSTTA/16/INF/28 and UNEP/CBD/SBSTTA/16/INF/29, respectively). The present volume comprises the edited versions of these studies. After being presented to SBSTTA, a limited number of additional references have been reviewed; these are identified in the footnotes. In addition, supplementary information on definitions of climate related geoengineering is provided in Annex II of Part I of this volume, as well as in Information Note UNEP/CBD/COP/11/INF/26, prepared for the eleventh meeting of the Conference of the Parties."
CBD Technical Series No. 66
Geoengineering in Relation to the
Convention on Biological Diversity:
Technical and Regulatory Matters
Part I.
Impacts of Climate-Related
Geoengineering on Biological Diversity
September 2012
https://www.cbd.int/doc/publications/cbd-ts-66-en.pdf page 16