Broecker had 6 children, 7 grandchildren, and 7 great-grandchildren. His wife Grace E. Broecker () died in 2007. They were together for 53 years. Broecker married Elizabeth Clark in 2009. He died of congestive heart failure in New York City on February 18, 2019. Days before his death, he gave a livestreamed video message to his fellow scientists, where he said that humankind was not moving quickly enough to stop global warming and urged the scientific community to "seriously study more extreme solutions to the climate crisis"