Soil and soil CO2 magnify greenhouse effect

TL;DR

This study reveals that soil and soil CO2 significantly contribute to the greenhouse effect through heat retention and transmission, emphasizing the importance of soil-related factors in global warming.

Contribution

It demonstrates the direct impact of soil CO2 and heat retention on greenhouse warming, highlighting a previously underappreciated mechanism.

Findings

Soil retains heat and releases it slowly, affecting Earth's heat balance.

Soil CO2 levels non-linearly influence soil temperature, peaking at 7500 ppm.

Soil and soil CO2 are crucial in driving the greenhouse effect.

Abstract

Soil has been recognized as an indirect driver of global warming by regulating atmospheric greenhouse gases. However, in view of the higher heat capacity and CO2 concentration in soil than those in atmosphere, the direct contributions of soil to greenhouse effect may be non-ignorable. Through field manipulation of CO2 concentration both in soil and atmosphere, we demonstrated that the soil-retained heat and its slow transmission process within soil may cause slower heat leaking from the earth. Furthermore, soil air temperature was non-linearly affected by soil CO2 concentration with the highest value under 7500 ppm CO2. This study indicates that the soil and soil CO2, together with atmospheric CO2, play indispensable roles in fueling the greenhouse effect. We proposed that anthropogenic changes in soils should be focused in understanding drivers of the globe warming.