alt Hacker NewsThe world will be greener in a high-CO2 environment. There’s no legitimate argument over that fact.
Where you go wrong is in misrepresenting the argument as “more plants and food”. That’s a straw man. Certainly it’s more favorable for growth of plants that make food, but that doesn’t mean that existing patterns of food production will exist unchanged, or that adaptation won’t be required. But we’re also talking about a 100+ year change timeline. People who tell you that this year’s weather are indicative of urgent, rapid change are exaggerating.
You seem to be willing to accept wild extrapolations of doom without evidence, while rejecting scientifically well-founded statements of fact, so I’d challenge you to examine your priors.
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At the levels of concentration of CO2 we’re seeing, plants are decreasing in size. Trees grow smaller.
There’s a balance to how much CO2 plants can adapt to and absorb while maintaining their growth and yields.
> The world will be greener in a high-CO2 environment. There’s no legitimate argument over that fact.
However it's important to remember that world isn't a high school physics experiment, and you can't easily separate out CO2 concentration from the other impacts of increased CO2:
| Climate change can prolong the plant growing season and expand the areas suitable for crop planting, as well as promote crop photosynthesis thanks to increased atmospheric carbon dioxide concentrations. However, an excessive carbon dioxide concentration in the atmosphere may lead to unbalanced nutrient absorption in crops and hinder photosynthesis, respiration, and transpiration, thus affecting crop yields. Irregular precipitation patterns and extreme weather events such as droughts and floods can lead to hypoxia and nutrient loss in the plant roots. An increase in the frequency of extreme weather events directly damages plants and expands the range of diseases and pests. In addition, climate change will also affect soil moisture content, temperature, microbial activity, nutrient cycling, and quality, thus affecting plant growth.
[https://www.mdpi.com/2073-4395/14/6/1236]
In global models of climate change the overall impact on plant growth is significant, but not positive:
| Global above ground biomass is projected to decline by 4 to 16% under a 2 °C increase in climate warming
[https://www.pnas.org/doi/10.1073/pnas.2420379122]
> Certainly it’s more favorable for growth of plants that make food
That does not seem to be what agricultural researchers believe:
| In wheat a mean daily temperature of 35°C caused total failure of the plant, while exposure to short episodes (2–5 days) of HS (>24°C) at the reproductive stage (start of flowering) resulted in substantial damage to floret fertility leading to an estimated 6.0 ± 2.9% loss in global yield with each degree-Celsius (°C) increase in temperature
| Although it might be argued that the ‘fertilization effect’ of increasing CO2 concentration may benefit crop biomass thus raising the possibility of an increased food production, emerging evidence has demonstrated a reduction in crop yield if increased CO2 is combined with high temperature and/or water scarcity, making a net increase in crop productivity unlikely
| When the combination of drought and heatwave is considered, production losses considering cereals including wheat (−11.3%), barley (−12.1%) and maize (−12.5%), and for non-cereals: oil crops (−8.4%), olives (−6.2%), vegetables (−3.5%), roots and tubers (−4.5%), sugar beet (−8.8%), among others
[https://pmc.ncbi.nlm.nih.gov/articles/PMC10796516/]