CO2Science found a 1999 paper done in China that shows just how awful climate change is for cotton. It’s a major global crop for fibre and oil and when the researchers warmed daytime growing conditions from 27C to 34C the plants seemed pretty happy about it as they grew faster and bigger. But if CO2 levels doubled as well, in hot conditions plant growth was up 60%. (Panic now. It’s a international emergency).
Don’t change your cotton futures portfolio just yet. At the current rate of warming (0.13C/decade) it will take about 500 years for Earth to get seven degrees warmer.
As reported by the Chinese scientists, at the end of the experiment (105 days after sowing), elevated temperature enhanced dry matter by 43% under ambient CO2 conditions and by 60% under elevated CO2 conditions (see Figure 1, left panel). Dry matter was also enhanced by elevated CO2 (17% under ambient temperature conditions and 31% under elevated temperatures). The highest increase in dry matter content was noted in the elevated temperature and elevated CO2 treatment, suggesting to the authors that “[CO2] enrichment could enhance the effect of rising temperature on dry matter content.”
Jones, C.G. and Hartley, S.E. 1999. A protein competition model of phenolic allocation. Oikos 86: 27-44.