Sir Patrick Vallance gave an updated version of this briefing - understood to contain the latest science - on Tuesday, with MPs tuning in to watch.
But it is understood that none of the 10 Tory leadership candidates joined in to watch the government’s chief scientific advisor’s presentation.
“That’s really disappointing,” Mr Rose told The Independent the following day.
The 52-year-old said it was “surprising” those vying to be prime minister did not want to make sure they were up-to-date on “the most pressing issue humanity faces” with leading scientists on hand to distill the key information.
“You would think hopefully they would do it for their country, for their community ... if they can’t do it for that, at least consider their own children, their own grandchildren,” Mr Rose added.
Driven by concern over the future of his nephews and nieces, Mr Rose went on hunger strike for 37 days to call for the briefing.
While in his third week, he told The Independent he hoped this presentation would improve decision-makers’ understanding of the climate crisis.
He also wants it to be made available to the public.
His protest came after Carbon Brief revealed the details of the slide show - delivered by the UK’s top scientists - believed to have sparked Mr Johnson’s “road to Damascus” moment on the climate emergency.
A number of MPs tweeted about listening into the briefing held by Sir Patrick, who was also joined by chief scientists at the Department for Food, Environment and Rural Affairs and the Met Office.
But as well as the absence of Tory leadership candidates, it has been reported only 70 MPs and peers - a small minority - turned up to watch.
“I could use a whole bunch of expletives,” Mr Rose told The Independent.
But he is now waiting to see who becomes the next prime minister and their position on the environment. “It’s up in the air still,” he said.
Other MPs have expressed alarm at the absence of Tory leader contenders at the briefing.
Wera Hobhouse, the Liberal Democrats’ climate change and energy spokesperson, told The Independent their “refusal to engage” in the presentation showed a “complete disdain to our planet and to Mr Rose who was on hunger strike for 37 days”.
“Climate change is the biggest issue that we are facing yet the Conservative leadership candidates are choosing to ignore it,” she said.
The MP added: “Instead, they are choosing to squabble over cutting taxes and dodgy logos.”
Layla Moran, another Lib Dem MP, said she attended the “fascinating and frightening” briefing.
“I’m sad that none of the hopefuls wanting to be our PM attended,” she added.
The Independent has contacted the Tory leadership contendeers for comment.