"It's really quite scary. It's apocalyptic," Penny Lee, a Sydney resident who flew into San Francisco International Airport on Thursday said. "I've lived in Sydney for 30 years and I've never seen it like this ever."
The fires are also having a devastating impact on wildlife. Nearly half a billion animals are feared dead. The koala population is particularly suffering.
"Already their numbers are threatened and now you add in these huge wildfires that are taking away again more trees, and that's compounding the problem and putting their numbers in real dire threat," Sarah King, a curator at the San Francisco Zoo explained.
Videos that show koalas parched, approaching humans while fighting for their lives have been shared all over the world.
Koalas have very particular needs. They only eat eucalyptus, which is also how they get their water.
"You don't often see koalas drinking water," King said. "When you do, it typically indicates that there may be something else going on with the animal."
People around the globe are stepping up to help. More than two million dollars has been donated to an Australian koala hospital.
Even when the fires end, there's a long road ahead.
"They're going to have to plant a lot of new trees," King said. "That's going to be the key thing, is planting more eucalyptus."
Spent the morning with Cynthia the Koala, and #swoon 😍— Liz Kreutz (@ABCLiz) January 2, 2020
My heart is breaking seeing the poor koalas threatened by the wildfires in #Australia. We’re at the @sfzoo learning more about these sweet animals & how all of us, even thousands of miles away, can help 🐨❤️@abc7newsbayarea pic.twitter.com/JoDmWiO2S3