The cost of ignoring climate change is "catastrophic", Environment Minister Eamon Ryan has warned.
He was speaking as a landmark report warns that the world's set to hit the global warming limit of 1.5 degrees Celsius in the next 20 years.
The United Nations review has found humans are unequivocally driving climate change, and some of the recent "unprecedented" changes are already irreversible.
It says heatwaves, flooding and droughts will be more frequent and intense, amid an already visible increase in extreme weather events.
"Every region on Earth" is being affected by the changes - from increasing temperatures to rising sea levels and changes in rainfall levels.
IPCC co-chair Valérie Masson-Delmotte said: “This report is a reality check.
“We now have a much clearer picture of the past, present and future climate, which is essential for understanding where we are headed, what can be done, and how we can prepare.
“It has been clear for decades that the Earth’s climate is changing, and the role of human influence on the climate system is undisputed."
However, the Intergovernmental Panel on Climate Change (IPCC) report says climate change can still be limited if there are "immediate, rapid and large-scale" reductions in emissions.
Speaking on Newstalk Breakfast, Environment and Climate Minister Eamon Ryan said there's now "no doubt" and "no debating" that human-driven climate change is happening right in front of us.
He said: "We have to remember what the science is saying: the cost of ignoring climate change is catastrophic.
"The scale of the change we need to make is so great that it won't work if it's done on a divisive basis, or if we leave some communities behind - it has to involve everyone."
He said it's vital to "not throw up our hands" and say we're doomed amid the increasingly stark warnings.
Minister Ryan said it's a major system change that's now needed, including moving away from the use of fossil fuels.
He said there needs to be major changes around land use and forestry, and that involves paying and supporting a whole new generation of farmers and foresters to help avert the crisis.