This study uses problems on advection fog from the Shandong Province College Entrance Examination geography papers as a representative of complex contextual problems and employs the think-aloud protocol to conduct an empirical analysis of 104 high-achieving second-year high school students. The results reveal three core obstacles in students’ problemsolving process: difficulty in dynamic process modeling, disorganized causal reasoning, and vague representation of geographical elements. Analyzing these challenges through the lens of cognitive load theory, their origins are attributed to excessive extraneous cognitive load, insuffi cient management of intrinsic load, and lack of relevant schemas. Accordingly, this study proposes three progressive instructional intervention strategies, practice demonstrates that the strategies can eff ectively reduce students' problem-solving burden, enhance their comprehensive competence in tackling complex geographical problems, and provide a teaching pathway grounded in cognitive science for fostering geographical key competences.