@blackangst1
"A top climate scientist is warning that climate change will wipe out all of humanity unless we stop using fossil fuels over the next five years"
First, break it down:
""A top climate scientist is warning that climate change will wipe out all of humanity"
Observe the lack of any time frame here.
"unless we stop using fossil fuels over the next five years"
There is a time frame in this part, but it revolves around when we need to have stopped using fossil fuels. Together it's saying that unless we've stopped doing stupid shit in the next 5 years, the process of climate change will have reached a point of no return and humanity will become extinct because of it. It does not specify how long the process will take to complete.
For example, if you have 5 miles of petrol left in your tank, you're approaching a petrol station and your passenger says to you, "There is no other petrol station nearby, you will run out of petrol unless you fill up now", they're not telling you that you will run out of petrol now, they're just telling you that you *will* run out of petrol during this journey unless you act now.