Rising CO2 won't make trees grow more, study suggests • Hacker News Board

Re: Rising CO2 won't make trees grow more, study suggests

#61

Post by radford-neal » Tue, Feb 05, 2019, 3:45 AM UTC

jellicle wrote: post #37

Plants may grow more easily, also wildfires may burn more easily, areas may get more water, also areas may get less water. Areas may be hotter, but also areas may be colder. The specific results that humanity gets depends on the particular weather patterns that we end up with, which are very difficult to predict, and thus the future holds a great many studies and predictions, most of which will be wrong in their spec…

Really??? UNDOUBTABLY headed to an APOCALYPSE???

Are you aware that this view is completely unsupported by anything resembling conventional science?

The IPCC estimate for equilibrium climate sensitivity for doubling of CO2 (which is about what is plausible) is from a 1.5 to a 4.5 C increase in average global temperature. The low end of 1.5C is not particularly worrying. Certainly not an "apocalyse".

If you weren't aware of this, you should stop confining your reading to alarmist propaganda.

Re: Rising CO2 won't make trees grow more, study suggests

#62

Post by Dylan16807 » Tue, Feb 05, 2019, 4:20 AM UTC

nwah1 wrote: post #28

amvalo wrote: post #15

Earlier quoted context omitted.

> The climate skeptics don't say tree trunks will get wider, they say there will be more plant biomass. Speculating that plant biomass might help mitigate global warming doesn't really deserve the label "climate skeptic." It's already confirmed that rising CO2 affects crop growth rates.

What do you mean by mitigate global warming? I think what they argue is that there will be winners and losers, and it isn't some kind of black and white issue. For instance, the Saharan desert seems to be greening.

'mitigate' in this case means that some extra carbon gets captured, slowing whatever happens down.

It's unrelated to the specific positives and negatives.

Re: Rising CO2 won't make trees grow more, study suggests

#63

Post by m0zg » Tue, Feb 05, 2019, 5:40 AM UTC

turndown wrote: post #45

mpg33 wrote: post #39

What is the right amount of CO2 to have in the atmosphere scientifically speaking?

An amount similar to levels before human impact.

There have been times "before human impact" when atmospheric CO2 was _way_ higher than it is now, though. You'll have to be more specific.

Re: Rising CO2 won't make trees grow more, study suggests

#64

Post by petre » Tue, Feb 05, 2019, 8:10 AM UTC

Maybe it doesn't speed up cedar tree growth but it certainly affects algae and fern growth.

http://theazollafoundation.org/azollas-uses/as-a-co2-sequest...

Re: Rising CO2 won't make trees grow more, study suggests

#65

Post by saalweachter » Tue, Feb 05, 2019, 2:21 PM UTC

mrpopo wrote: post #59

nwah1 wrote: post #46

Earlier quoted context omitted.

>Factorial simulations with multiple global ecosystem models suggest that CO2 fertilization effects explain 70% of the observed greening trend, followed by nitrogen deposition (9%), climate change (8%) and land cover change (LCC) (4%). https://www.nature.com/articles/nclimate3004

I acknowledge that CO2 contributes to fertilisation. I was refuting the claim about the saharan desert. Your new link doesn't seem to contradict me : > CO2 fertilization effects explain most of the greening trends in the tropics

Incidentally the second (earlier) paper is cited by the first (newer) paper, so hopefully they are not in contradiction (since it was merely referenced and not responded to).