Nature has been equipped with balanced proportions of everything and whenever this balance gets disturbed, it has a strange way to readjust itself. History is witness to a number of mass extinctions that occurred in past as a way of nature to regain its balance.
Earth has been subject to five mass extinctions in the past 540 million years. Coincidentally, each of them was brought about due to upending of normal carbon cycle through oceans and atmosphere, causing millions of species to disappear completely.
Professor Daniel Rothman from IT Department of Earth, Atmospheric and Planetary Sciences and co-director of MIT’s Lorenz Center believes that another mass extinction is just about to happen again.
Since 19th century, carbon dioxide emissions have been on a rise. However, it can’t be predicted that the recent spike in greenhouse gas emissions could lead to another mass extinction since ancient carbon anomalies might not be analogous to today’s disruptions. Nonetheless, Professor Daniel Rothman would like to disagree.
In his recent paper, he proposed two thresholds to be crossed for a mass extinction to occur:
- If changes in carbon cycle occur over a prolonged period of time, extinctions are more likely to happen if the changes occur at a faster rate than global ecosystems can adapt.
- If changes in carbon cycle occur over shorter period of time, it doesn’t matter how fast or slow the change is occurring, instead, what matters is the magnitude of change that eventually determines the likelihood of an extinction.
Based on these arguments, Rothman predicts that since the recent rise of carbon dioxide emissions has occurred over a relatively shorter period of time, the sixth extinction is solely dependent on amount of carbon added to the oceans. This threshold amount, as calculated by Rothman, is about 310 gigatons which is roughly equal to the estimated amount of carbon that will be added to oceans by human activity by the year 2100.
However Ruthman is hopeful that if human beings still find a way to keep control on carbon dioxide emissions and would be able to reduce them, the chances of sixth mass extinction to occur are slim, at least for some time.
Do you believe his analysis? Let us know in the comments section
