According to extant literature, runaway photosynthesis describes a scenario in which the machinery of photosynthesis could be adversely affected by shifts in the environment, leading to the crumbling of all ecosystems that depend on it for survival (Dartnell, 2011). In particular, the expression “runaway photosynthesis” is mainly used in the mainstream media and by environmental experts with reference to positive or negative feedback effects that could affect the photosynthesis process due to changes occurring within the environment (Cox et al., 2011). This paper illuminates how the phenomenon of runaway photosynthesis affects life in the universe.
Animal life as is known today requires an atmosphere with adequate oxygen, whereas plants require a sufficient amount of carbon in the atmosphere in the form of carbon dioxide (CO2) for photosynthesis to occur (Global Climate Change, 2002). Scientific investigations have proved that vegetation and soil contain about three times as much carbon as the atmosphere, and that at the present time the land is absorbing about a quarter of anthropogenic CO2 emissions released by various activities in the biosphere because uptake of CO2 by plant photosynthesis is surpassing respiration from soils (Cox et al., 2011).
However, as acknowledged by Cox et al (2011), a number of scholars “have discussed the possibility of the land carbon sink either saturating or reversing primarily because of the potential for accelerated decomposition of soil organic matter under global warming” (p. 155). Such a scenario could definitely lead to runaway photosynthesis not only due to lack of a stable habitable temperature occasioned by the unstable mixture of greenhouse gases, but also because of the probability that “feedbacks” between the climate and the land biosphere may substantially accelerate or suppress atmospheric CO2 and land carbon uptake (Dartnell, 2011).
The problem of runway photosynthesis lies in its capacity to substantially accelerate atmospheric CO2, leading to the negative effects of global warming and dangers associated with greenhouse emissions. Cox et al (2011) note that “whilst increases in atmospheric CO2 are expected to enhance photosynthesis (and reduce transpiration), the associated climate warming is likely to increase plant and soil respiration” (p. 155). Climate warming as a direct consequence of sudden drop in photosynthesis and reduced removal of carbon dioxide from the atmosphere is known to expose animal species to the harmful ultraviolet (UV) light and could also make life on earth impossible as too much carbon in the atmosphere is disastrous to life (Dartnell, 2011; Global Climate Change, 2002). A runway greenhouse effect occasioned by too much carbon in the atmosphere will certainly cause the earth’s surface temperature to rise to levels that cannot sustain plant or animal life on earth.
According to available literature, “it is estimated that photosynthesis is a sink for around 60 billion tons of carbon every year, by far the strongest mechanism for carbon dioxide removal from the atmosphere” (Global Climate Change, 2002 para. 2). However, although increases in the level of carbon dioxide in the atmosphere is good for plant growth, a lack of balance between the increases and the respiration of animals may have the capacity to trigger runaway photosynthesis and hence destroy many species that live in very sensitive ecological niches. For example, small shifts in temperature rise or precipitation drastically affect the capacity of Oak tress to survive, not mentioning that an increase of as little as 1°C in ocean temperature over two or three days could “bleach” corals due to loss of their symbiotic algae which is fundamental for their nutrition. Humans cannot survive under extreme temperatures or within environments with a very high volume of carbon dioxide (Global Climate Change, 2002). Essentially, therefore, the phenomenon of runaway photosynthesis adversely affects life in the universe in multiple ways, hence the urgent need to preserve the environment.
References
Cox, P.M., Huntingford, C., & Jones, C.D. (2004). Conditions for sink-to-source transitions and runaway feedbacks from the land carbon cycle. In H.J. Schellnhuber & V.P. Cramer (Eds.), Avoiding dangerous climate change: Key vulnerabilities of the climate systems and critical thresholds (pp. 155-176). Cambridge: Cambridge University Press.
Dartnell, L. (2011). Astrobiology: Exploring life in the universe. New York, NY: The Rosen Publishing Group.
Global Climate Change. (2002). Overview of climate change research: Biosphere. Web.