The streets of Brasilia, Brazil’s capital, erupted in celebration at the inauguration of the nation’s new president on 1 January 2023. Chants of “Ole, ole, ola, Lula, Lula!” welcomed the new head of state, Luiz Inácio Lula da Silva, who has pledged to restore protections for the country’s Amazon rainforest. Just weeks into his term, that promise is already being tested, as the emergence of fresh carbon market schemes in the Amazon brings with it a new and poorly understood opportunity and...