The wife of Victorian Greens Senator Jane Rice, renowned climate scientist and transgender woman Penny Whetton, has died suddenly, the senator has announced.

In a post on Facebook, Senator Rice said her partner of almost four decades died “suddenly and apparently peacefully” at their house in Sisters Beach, Tasmania, last Wednesday. She was 61.

“She was alone, having arrived at Sisters on Tuesday to spend a week or two while I was in Canberra,” Senator Rice wrote in the post.

“The last anyone heard from her was early Wednesday evening, and she was found on Thursday morning, still sitting on the couch, computer on her lap.

“She was in her favourite spot in one of her favourite places in the world — a lovely place to pass away, but just 20 years too early!

“It’s so unbelievable, so unexpected and so, so sad.

“Penny and I had been a team for almost 38 years. She was my rock, my best friend, my biggest fan. She was proud of me and I of her.”

The couple married in 1986.

Senator Rice wrote Dr Whetton was a “fabulous parent” to their children John and Leon, “always supportive, giving, and delighted in sharing her and their passions — language, music, football, cricket, politics, painting, photography…”.

Dr Whetton led the CSIRO’s national climate projections work from 1992 to 2014 and was a lead author of three Intergovernmental Panel on Climate Change reports, including the fourth assessment report which was awarded the Nobel Peace Prize in 2007.

“She was deeply angry about current politics that is hurtling us to avoidable climate crisis, and deeply worried about the damage being done and the future prospects for our precious natural world,” Senator Rice wrote.

“She was so worried about the coming summer.”

The couple met and married when Dr Whetton was living as a man.

In a 2017 interview with the ABC, she spoke of fearing that her decision to become a woman would end their marriage.

Senator Rice said she couldn’t imagine life without Dr Whetton. Photo: ABC/Danielle Bonica

“I was afraid for years by even admitting to this that it would lead to the end of the relationship, that’s why it took me so long because the relationship was so incredibly important,” Dr Whetton said at the time.

Senator Rice said she was “a role model and an inspiration for so many trans and gender diverse people”.

She described her wife as “a scientist and artist, intelligent, creative and able to turn her hand and her intellect to almost anything, from the climate science that was her profession, to landscape painting and furniture making”.

“She was principled and loyal, a collaborative leader, and a mentor to many,” Senator Rice said.

“She was happiest with camera in hand in a misty day in a tall wet forest — absolute favourite being a myrtle beech forest — or striding out across mountain ranges, or in the early morning on the beach at Sisters, photographing the morning light and chatting to the Pacific Gulls and Sooty Oyster Catchers.

“It’s still not real. I can’t imagine life without her. I know so many of her friends and colleagues feel the same.

“We’ll get through I suppose, but we will miss her so so much.”

Senator Rice said she planned to set up a memorial fund in her wife’s name to fund revegetation and erosion control work at Sisters Beach.

-ABC