Hong Kong CNN  — 

Scientist Sandy Song remembers when she first saw the aggressive swirl of the monster storm approaching on satellite images at her office at the Hong Kong Observatory.

“I was afraid,” she says. “It had a very sharp eyewall and also the intensity was very strong. It was a super typhoon.”

Song is a professional storm watcher who is becoming increasingly worried about the impact of climate crisis on the towering coastal city, home to seven million people.

The super typhoon she was describing was Mangkhut, which churned its way across the South China Sea, killing dozens of people in the Philippines and southern China in September 2018.

Mangkhut also slammed into Hong Kong, with wind gusts of up to 256 kilometers (159 miles per hour). Before the storm hit, the Observatory issued its highest level warning – Typhoon Signal Number 10.

The ferocious storm system wreaked the worst damage the densely populated city had seen in decades. And yet, Hong Kong escaped without any loss of life.

In part, the city got lucky. The storm did not make landfall during high tide, which could have caused much more destructive storm surges.

“Otherwise,” Song says, “the devastation would have been even worse.”

Song and the other scientists at the Observatory are charged with warning this vulnerable coastal city about the threat of extreme weather.

“We have no doubt that climate change is happening right now,” Song says.