Penelope Whetton (5 January 1958 – 11 September 2019) was an Australian climatologist. She was an expert in regional climate change effects due to global warming and in the impacts of those changes. Her primary scientific focus was Australia.
In 1989, she joined the Atmospheric Research division of CSIRO (later becoming CMAR CSIRO Marine and Atmospheric Research). She was one of the lead authors of the Fourth Assessment Report of the Intergovernmental Panel on Climate Change.
Whetton was born in Melbourne. She was married to Senator Janet Rice. In 2003, she had sexual reassignment surgery. Whetton died on 11 September 2019 in Sisters Beach, Tasmania at the age of 61.