Teenagers have been bursting into the conversation surrounding climate change — passionately advocating for the planet and their future living on it. But this college student is making her activism even more personal by pledging not to have children until leaders take action.

Canadian teen Emma Lim told CBS News she made the decision a few months ago not to have children in the future due to the climate crisis. "Because even though I want to have children more than almost anything, what kind of a mother would I be if I brought a baby into a world where I couldn't make sure they were safe?" she wrote on her website.

From there, she and a friend decided to create a website where others could "pledge" not to have kids as well, creating the hashtag #NoFutureNoChildren.

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"The name comes because we really feel often like we have no future, or that our government doesn't care about the future," she told CBS News. "And so we don't feel able to have children if their future isn't going to be safe."

The 18-year-old McGill University student launched her pledge on Monday at Canada's Parliament Hill and was surprised by the response. "I thought the pledge would be a hard sell — but of the 100 or so friends I sent it to in the beginning, only two or three declined to sign it," she said. "Climate change in my generation is objective fact, and it seems like the fear I have when I think of the future is something most people are feeling too."

Over 900 people have pledged "not to have children until I am sure my government will ensure a safe future for them" on the site. The page has a "stories" section where those who have signed the pledge discuss their reasons for doing so.

Lim (left) poses on Parliament Hill at the announcement of her pledge #NoFutureNoChildren. Emma Lim

"The science is clear: We are about to witness the destruction of everything we love because of the climate crisis," wrote Allie Rougeot, a 20-year-old native of Ontario, Canada. "I feel incapable of welcoming an innocent human being into this world knowing the facts."

"Our government is doing too little to protect the climate and thus our region," said 18-year-old Jacob Diercks of Germany. "Where I live will be flooded soon and there is nothing I can do to save this place for my children."

While some have brushed the movement off as something young people will outgrow as they age, Lim said that's not the case — unless something changes.

"To people who say I'll change my mind, I'll say that I hope I do," she told CBS News. "I'm the kind of person who makes lists and ten-year plans, and changing my long terms plans now is not something I do easily. It's a really adult decision that I'm having to make because my leaders are acting like children."

The biomedical science student said that to reverse the pledge, she would want to see real change. Lim explained she expects the Canadian government to develop a plan to reduce emissions, focused on limiting the warming of the planet, as well as a "mitigation plan" for those who have already been harmed by the climate crisis.

"Every nation does not have to act, because not every nation is equally responsible for climate change," she said. "But in Canada, inaction is not an option."

Lim's decision has had impacts beyond just herself, she admitted.

"It really hurt my parents, I think, because for the first time they were able to feel the effects of the climate crisis," she said. "In Ontario we are seeing once-in-a-hundred year floods happening every year, but those effects are nothing compared to suddenly realizing you won't have grandchildren. I think the pledge made my parents take the issue of climate change seriously, and it made them read the science."

The young activist said she always wanted kids, but is choosing not to until the climate crisis is mitigated. Emma Lim

Lim's launch came one day before world leaders were to meet at the United Nations General Assembly in New York, where the Earth's changing climate is a top item for discussion. The U.N.'s Climate Action Summit begins on September 23 and is preceded by the Youth Climate Summit — a gathering of young global climate campaigners who have organized worldwide demonstrations this year.

In 2016, 174 countries and the European Union signed onto the U.N. Paris Agreement, which aims to prevent global temperatures from rising 2 degrees Celsius through "nationally determined contributions." But President Trump left the agreement in 2017, laying the groundwork for the Trump administration's environmental deregulation policies.

A recent CBS News Poll found that a majority of Americans say action needs to be taken right now to address climate change. Most consider it to be at least a "serious problem" — including more than a quarter who say it is a "crisis."