“I’ve been [in] helicopters in the West, in the Southwest and Northwest, flown over more land burned to the ground, all the vegetation gone, than the entire state of Maryland,” Biden told his audience, partly referring to the wildfires now raging in Texas. “The idea there’s no such thing as climate change, I love that, man," the president added with evident sarcasm. "I love some of my Neanderthal friends who still think there’s no climate change.”
The root cause is well known - greenhouse gases, largely from extracting and burning fossil fuels:
It matters that US greenhouse gas emissions have been falling and that he helped pass legislation to accelerate that fall, has also taken steps under existing regulatory authority to cut them, and has appointed judges likely to uphold those laws and regulations
A number of smaller countries have higher per-capita emissions