Dino impact gave Earth the chill

Evidence has been found for a global winter following the asteroid impact that is thought to have killed off the dinosaurs 65 million years ago.
Rocks in Tunisia reveal microscopic cold-water creatures invaded a warm sea just after the space rock struck Earth.

The global winter was probably caused by a pollutant cloud of sulphate particles released when the asteroid vapourised rocks at Chicxulub, Mexico.

I thought the main impact that wiped out the dinosaurs was recently reported to be in Australia?