Irish children are writing to Santa with wish lists for the environment that they want him to deliver to world leaders.
They're telling him of their fears about climate change and the loss of nature and are pleading with him to make the adults listen.
Dear Green Santa is the idea of scientist Dr Laura Kehoe who is gathering the letters to send to delegates at the UN climate summit in Madrid next week.
She has been taken aback by the depth of knowledge some very young children have and by the poignancy of their pleas.
"Parents are surprised too," she said.
"The mother of one nine-year-old boy who wrote a letter that was just heart-breaking had no idea her son knew so much or was so worried.
"So it's a really good exercise for exploring what your child knows and how they feel. We know Santa will pass their messages on and remind the politicians they need to be good too."
Green Santa will be at a pop-up grotto on Grafton Street, Dublin, on Sunday from noon to 3pm where children can leave letters. They can also share them on deargreensanta.org
It's almost a year since I started striking - and it feels like forever. We shouldn't need to do this. At the start, I thought the Government would take action. It has but it's just not of the enormous size or radical kind that's needed.