"The science says we have only until 2030 to achieve these reductions before it will be too late and it won't matter what we do."
You have two major misunderstandings in that short statement:
1. What the science says is to limit warming to 1.5 degrees we would need to reduce greenhouse gas emissions by ~45% by 2030.
What it also says is that to achieve a limit of 2 degrees we'll need to reach net zero carbon emissions by 2050.
2. The science also tells us there are reduced impacts from minimising temperature rises to 1.5 degrees versus 2 degrees, and for achieving 2 degrees rather than 3, and for not exceeding 3 degrees rather than reaching 4 degrees warming or higher.
What the science says is that every action to reduce the amount of warming has benefits, because of reduced impacts. It doesn't say it would otherwise be too late and it doesn't say it won't otherwise matter what we do.
Every bit counts in terms of reducing impacts.
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The science leaves the value judgement of how much mitigation versus adaption we go for, and hence whether we aim for 1.5 degrees or 2 degrees up to the political process.
It is the political process that determined the goal of limiting warming to 2 degrees or less, based on science and economic studies of the effects of warming. The 1.5 degree assessment was more recently requested by political leaders, and the science showed benefits of achieving that.
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It strikes me that the sort of miss-statement you've made illustrates the extent to which the science denial camp is emotional and disconnected from the facts and science on this. It seems pretty clear that every time we have the denial talking points of religion and fear, they are talking from their own perspectives and projecting that onto the science.
Some of you seem smart enough to get over that. But it is sure taking you guys a long time.
