To address the uncertainty of renewable energy output and the fragmentation between green certificate and carbon trading markets, a distributed robust optimization scheduling method for multi-regional integrated energy systems based on a green certificate-carbon trading joint mechanism is proposed. Firstly, an interconnected architecture for multi-regional integrated energy systems encompassing electricity, heat, gas, and cooling multi-energy flows is constructed. Secondly, a price-linked green certificate-carbon trading joint interaction mechanism is designed. By introducing a dynamic conversion coefficient, the transformation relationship between the environmental rights of green certificates and carbon quotas is quantified, capturing the value transmission process between the green certificate-carbon trading markets, thereby achieving synergistic incentives for the environmental value of both markets. Finally, a two-stage distributionally robust optimization scheduling model is established, aiming to minimize the system's comprehensive operating costs, based on constructing a fuzzy set for the probability distribution of wind and solar power output under comprehensive norm constraints. Case study results demonstrate that the green certificate-carbon trading joint mechanism can effectively reduce system operating costs and carbon emission levels.