While visiting the flood-ravaged Lismore region in northern NSW, the prime minister said he understood the impact the changing climate was having on national security.
"I've said as much in the past, we are dealing with a different climate to the one we are dealing with before," he said.
"I think is just an obvious fact in Australia is getting hard to live in because of these disasters."
But he shrugged off criticism of the government's climate policies, saying Australia is impacted by the changing climate globally and unilateral action by the country wouldn't impact natural disasters.
"I'll tell you what's not going to fix climate change ... doing something in Australia and then in other developing countries their emissions continue to rise," he said.
"The real challenge of addressing climate change is ensuring that we're working with other countries in the region and particularly developing countries to ensure we have the technology."
He was met with a barrage of climate protesters as he arrived at the Lismore Emergency Operations Centre to address the media.
Protesters called for Mr Morrison to declare a climate emergency and to do more on climate action.
Deputy Prime Minister Barnaby Joyce earlier warned Mr Morrison would not receive a warm welcome from locals during his visit.
"People are incredibly vulnerable, and it's understandable that they want to express that and the pain that they're going through," Mr Joyce told Sky News.
"I would be incredibly surprised if people got a happy reception, because they're not in a happy place, and they want to be heard."