Why can't Nima release his gas into the world in Snowpiercer?

When Melanie returned in Snowpiercer Season 4, Episode 7, she had some bad news for Nima. He can’t release his gas yet as it will mean certain death for everyone.

Nima is obsessed with saving the world. We learned at the end of this episode that’s because Nima was the one to create the big freeze in the first place. Since then, he has been obsessed with fixing his mistake. The problem is that his science is flawed.

Melanie has noticed that. Her tests show that Gemini is going to destroy the Earth even more. He needs to wait.

Nima could permanently end the world in Snowpiercer

If Nima goes ahead with his plan, Melanie shares what could happen. All of the Earth’s oxygen would be replaced. Without oxygen, the human population cannot survive. It’s instant death for everyone.

Alex’s bird proved this. Alex’s nosebleeds show that something is going to happen, and she isn’t alone in having them. Nima is so sure that Gemini is perfect that he is willing to risk it all, and Melanie can’t let that happen. Well, it looks like Melanie won’t have a choice.

Sure, we know that Melanie isn’t always right. When she came back with her findings during the third season, she said that there wasn’t a piece of land that could support life. Plus, the bridge was rickety, which could mean there would be no way to move out of New Eden if it proved to be a frozen wasteland. Fortunately it didn’t, but Melanie couldn’t risk what she found based on her science.

She doesn’t want to risk what is left of the human race. If she believed that there was a bit of her research that was wrong, she’d go ahead with Nima’s plan. However, she knows that Nima has it wrong. There are already versions of Gemini that prove he isn’t the greatest chemist. He gets his science wrong, and he ends up making people sick. She doesn’t want him to end all of humanity.