Data Observation Network for Earth (DataONE) is the foundation of new innovative environmental science through a distributed framework and sustainable cyberinfrastructure that meets the needs of science and society for open, persistent, robust, and secure access to well-described and easily discovered Earth observational data.
Google Dataset Search is a search engine from Google that helps researchers locate online data that is freely available for use. The company launched the service on September 5, 2018, and stated that the product was targeted at scientists and data journalists.
Funded by the OpenAIRE Consortium (an open access network) and CERN, the European Organization for Nuclear Research. The site is a non-profit and integrates easily with your GitHub account. It allows users 50 GB of storage for each dataset, though you can contact them and lobby for more.