Unmanned Aerial Vehicles (UAV) networks face numerous challenges in dynamic jamming environments, particularly when frequent short-term fluctuations in link quality occur. Traditional routing protocols operate at the network layer, and there is a latency in feedback on link quality. Frequent fluctuations may even lead to route oscillations and packet loss. To address this challenge, this paper proposes a cooperative cross-layer routing (CoRt), breaking away from traditional models by allowing the network layer routing protocol to plan multiple route paths and provide several candidate next hops to the link layer. The link layer dynamically selects the optimal next hop based on related jamming information, thus avoiding issues such as delayed link quality updates and route oscillations. Additionally, this approach offers greater flexibility for optimization at both the network and link layers. We implement the protocol on a commercial network simulator EXata. The results demonstrate the effectiveness of our routing protocol in complex dynamic environments, significantly improving the communication stability and efficiency of UAV networks.