The optimal levels of CO2 are those levels to which all life on earth and our current society have adapted to.
What is the optimal sea level for New York? The one that allows ships to go into the ports we built but doesn’t flood the city, i.e. the current sea level. If the sea levels were 100 feet lower New York would have been built been built further towards the sea, if they have been 100 feet higher it would have been built further away. But since it was built with the current sea level in mind that is that best place for it and increasing it by 100 feet would be a disaster (example only for illsutration not claiming that sea levels will actually rise this much). Similarly with CO2, if CO2 levels were higher or lower biology would have changed, and assuming humans had still evolved we would place our cities in areas that reflected that climate. But now over the past hundred years or so CO2 levels have radically increased to levels not seen in millions of years, a level that our civilization and our environment are ill suited for.
All models seem to agree that we are already well past that point. At this point we the best we can try to limit how bad things get.
Well there is always a first time to be a contrarian of the evidence . Remember, you are not able of citing any scientist defending your position here. The reality is that when you insist that the proponents of change are talking about going cold turkey on fossil fuel, that is not the case. That talking point is standard issue from the denialosphere also. No serous researchers or policy makers advises to “suddenly” stop the use of carbon fuels. This talking point is tailor made to make others distrust the proponents of change and the scientists, but in general it is just a straw man, don’t fall for that one.
Going back though to your decades debunked point about not worrying because plants will deal with the excess carbon; the reality is that the few gains one can get for beneficial plants are overwhelmed by the damages caused by the increases in heat and other effects caused by the increase of CO2 that we are adding to the atmosphere.
So far what me and others see is that your sources are not convincing the scientists that research the issue. To be fair, when your sources amount to little, they are not worthy of much support.
I agree with what others pointed out, even being correct on CO2 benefiting some plants, the reality is that debating on this is a bit of a red herring, research done before shows that most plants will not do so well in a warming world. And besides this “debate” also ignores the other evil twin of issues coming by increasing CO2 besides global warming: ocean acidification.
Actually, I am. But not because of climate change. It’s because we’re irredeemably selfish, short-sighted, and violent. Climate change is one manifestation of that, and the one that is probably going to kill us. However that is clearly a different thread I’m not going to start.
No comment on the OP’s specific recommendation, so really just answering the title:
If there were no environment - i.e. we were just living in a vacuum - then we’d all die so, technically, yes the environment is worth at least 1% of the world’s economy. Without it, there would be no economy.
That being said, if fixing the environment could be accomplished at a cost of 0.5% of the economy then that would be better since it leaves more money and labor for other things. Why spend more than you need to? Likewise, if fixing the environment requires 1.5% of the economy then putting 1% towards it is ultimately not useful. Doing things without thinking about it or trying to right-size it is, fundamentally, the sort of approach to things that gets us to a place where we have to worry about the environment.
. Remember, you are not able of citing any scientist defending your position here. The reality is that when you insist that the proponents of change are talking about going cold turkey on fossil fuel, that is not the case. That talking point is standard issue from the denialosphere also. No serous researchers or policy makers advises to “suddenly” stop the use of carbon fuels. This talking point is tailor made to make others distrust the proponents of change and the scientists, but in general it is just a straw man, don’t fall for that one.
