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PaperclipPerfector  8d ago (text post)   2299 thread views

Small-Scale Question Sunday for December 21, 2025

Do you have a dumb question that you're kind of embarrassed to ask in the main thread? Is there something you're just not sure about?

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CO2 have resulted in greater agricultural productivity for our plants already

do you have numbers for it? Is it greater at high altitudes where one could expect CO2 increase produce larger impact in %?

do you have numbers for it?

Since the industrial revolution we went from 290 ppm CO2 to 424 ppm.

From 2002 to 2014, plants appear to have gone into overdrive, starting to pull more CO2 out of the air than they have done before.[33] The result was that the rate at which CO2 accumulates in the atmosphere did not increase during this time period, although previously, it had grown considerably in concert with growing greenhouse gas emissions.[33]

A 1993 review of scientific greenhouse studies found that a doubling of CO2 concentration would stimulate the growth of 156 different plant species by an average of 37%.

A 2005 review of 12 experiments at 475–600 ppm showed an average gain of 17% in crop yield, with legumes typically showing a greater response than other species and C4 plants generally showing less.

https://en.wikipedia.org/wiki/CO2_fertilization_effect#Observations_and_trends

We report a strong enhancement of photosynthesis across the observational network (9.1 gC m−2 year−2) and show that the CFE (CO2 Fertilization Effect) is responsible for 44% of the gross primary production (GPP) enhancement since the 2000s, with additional contributions primarily from warming (28%) .

https://pmc.ncbi.nlm.nih.gov/articles/PMC8915860/

Here we use three long-term satellite leaf area index (LAI) records and ten global ecosystem models to investigate four key drivers of LAI trends during 1982–2009. We show a persistent and widespread increase of growing season integrated LAI (greening) over 25% to 50% of the global vegetated area, whereas less than 4% of the globe shows decreasing LAI (browning). 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%). CO2 fertilization effects explain most of the greening trends in the tropics, whereas climate change resulted in greening of the high latitudes and the Tibetan Plateau.

https://www.nature.com/articles/nclimate3004

Is it greater at high altitudes where one could expect CO2 increase produce larger impact in %?

I don‘t think so. According to this map, the CO2 fertilization effect is stronger at the equator, where there are more plants, more primary production already (rainforest) . Then less as you get further away from the equator. The quote above suggests plants at high latitudes need warmth more than CO2.

thanks

i meant altitude, not lattitude (-:

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