Why does GPU temperature spike to 82 degrees in rainforest scenes?

Heat buildup in dense foliage caused the GPU to hit 82 degrees, triggering throttling. I tried lowering textures, but frame rate still dropped to 30 FPS. Using GamePP Fan Curve Configurator, I set 60 degrees to 85% speed. Temperature stabilized at 68-74 degrees per AIDA64, and frame rate recovered to 80-88 FPS.