There is a pretty important news story, regarding climate change and how carbon dioxide has been shown to increase global temperatures pretty dramatically by NASA.
A study by GISS climate scientists recently published in the journal Science shows that atmospheric CO2 operates as a thermostat to control the temperature of Earth.
This has been a hotly debated topic among the denialist groups for years, but their claims have repeatedly proven to be false. NASA now has a new study that shows that atmospheric carbon dioxide acts like a thermostat on water vapor, which traps heat on the planet.
Fluctuations between 180 ppm of CO₂ and 280 ppm have been documented in the Earth’s past. Life on Earth flourished within these “interglacial maximums”, however, we are now well past those established ranges, nearing 400 ppm.
It has been suggested that we are well past the 300 to 350 ppm target level for atmospheric CO2 beyond which dangerous anthropogenic interference in the climate system would be expected to exceed the 25% risk tolerance for impending degradation of land and ocean ecosystems, sea level rise, and inevitable disruption of the socio-economic and food-producing infrastructure (Hansen et al. 2008). This prospect of a rising risk of triggering unacceptable environmental consequences makes reduction and control of atmospheric CO2 a serious and pressing issue for humanity, worthy of real time attention.
Radiative modeling analyses of the terrestrial greenhouse structure described in a parallel study in the Journal of Geophysical Research (Schmidt et al., in press) found that water vapor accounts for about 50% of the Earth’s greenhouse effect, with clouds contributing 25%, carbon dioxide 20%, and the minor greenhouse gases (GHGs) and aerosols accounting for the remaining 5%, as shown in Fig. 1. Thus, while the non-condensing greenhouse gases account for only 25% of the total greenhouse effect, it is these non-condensing GHGs that actually control the strength of the terrestrial greenhouse effect since the water vapor and cloud feedback contributions are not self-sustaining and as such, only provide amplification. Because carbon dioxide accounts for 80% of the non-condensing GHG forcing in the current climate atmosphere, atmospheric carbon dioxide therefore qualifies as the principal control knob that governs the temperature of Earth.
Essentially, NASA has now shown that CO₂ is the “on-off” switch for a habitable climate within a fairly narrow range. We have far, far exceeded that range now, which is why we are experiencing the degradation of land and ocean ecosystems throughout the world.
The bottom line is that atmospheric carbon dioxide acts as a thermostat in regulating the temperature of Earth. The rapid increase in atmospheric carbon dioxide due to human industrial activity is therefore setting the course for continued global warming. Because of the large heat capacity of the climate system, the global surface temperature does not respond instantaneously to the sharp upturn of the carbon dioxide thermostat, which at this moment stands at 386.80 ppm compared to the normal interglacial maximum level of 280 ppm. Since humans are responsible for changing the level of atmospheric carbon dioxide, they then also have control over the global temperature of the Earth. Humans are at a difficult crossroad. Carbon dioxide is the lifeblood of civilization as we know it. It is also the direct cause fueling an impending climate disaster. There is no viable alternative to counteract global warming except through direct human effort to reduce the atmospheric CO2 level.
There are two more articles worth studying:
Water Vapor Confirmed as Major Player in Climate Change – Water vapor throughout the troposphere reacts to global surface temperatures, amplifying feedback.