But, will we not need a global institution to accomplish this design?

Yes, it might be necessary, and it would have unique responsibilities:

To ensure a diverse biosphere, to manage common resources, to protect unique cultures, and to represent them. This means there has to be some global political framework. That is, any global ecological design has an economic and political aspect.

A global framework would start by recognizing that our bad circumstances and fast change are leading to disaster and require immediate change.

The International would manage the national, which would manage the community. But, the community values and needs would feed back into the regional and global. The community would do the innovation and work within the restraints.