I think we all have seen or heard of the movie called Jurassic park, well have you all heard of the Holocene and Anthropocene well the great debate between the two. The debate currently ongoing is when should the Anthropocene actually start, well there are two strong candidates for when it should start and we are going to look at the credibility of each and if they fulfill the requirements defined by the International Commission on Stratigraphy.
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| Aztec vs Spanish Conquistadors |
The most important thing when it comes to dividing geological-scale time is that Earth experiences Global-scale changes to its earth systems driven by forces unique to that time period. The Holocene is often referred to the age of main while the Anthropocene has a similar meaning as it denotes the geological time period which humanity is the driving force of systems within earth. The problem arises in that when one decides to state the Anthropocene as a geological epoch, Maslin says we would be depriving the Holocene of what actually makes it unique-human- but we wont be looking into that in this blog. We are going to be discussing the credibility of 1610 and 1950 as possibly starting dates of the Anthropocene.
1610:
The earliest starting date for the Anthropocene suggested by Maslin is 1610 as it coincides with lowest carbon dioxide levels of 271.8 since the last ice age recorded in the Law dome Ice core. The decrease in atmospheric carbon dioxide was caused by the arrival of Spanish conquistadors in the Americas in 1492, with their arrival spelling the end of the native population from roughly 61 million to 6 million by 1650. The decrease in native populations is often synonymous with colonization as Europeans went on their god ordained massacre of the natives via warfare and disease like chicken pox which wiped out the Aztec and Inca kingdoms of the old worlds. The reduction in human population as Maslin points out in his study caused the decline of farming, allowing the regrowth of native vegetation which sequestrated 7-10 ppm carbon dioxide which is documented in two high resolution Antarctic ice core records. This dip is atmospheric carbon dioxide is often referred to as the Orbis spike. The geological ice records of this Orbis spike is important as it means that both criteria of the International commission of Stratigraphy as the ice records are a GSSA and the clash of the old and new worlds signaled a shift in the dynamics of the earth as the transoceanic transport of species has no equal in geological history as Maslin points out in his study.
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| Great Acceleration Graphs |
1950:
The next candidate for the beginning of the Anthropocene is 1950, as beyond this point in time there is clear evidence for fundamental shifts in the nature and functioning of the Earths Systems that are beyond normal variation as experienced in the Holocene as these graphs from the study conducted by Steffan et al point out. This time is often referred to as the Great Acceleration as its the time when human invention, fossil fuel consumption, deforestation and global environmental impact accelerate to levels never experienced before. A number of reasons for this increase in human impact are given as the industrial revolution had passed and two great wars had passed in Europe which allowed rapid advancement in human innovation and technology, nuclear bombs had been tested and used and the beginning of the cold war was in full swing. The Graphs of the Great acceleration point to the undeniable truth that humans are in fact in complete control of environmental change, with rates of change often unparalleled in geological time. When it comes to GSSA or GSSP the great acceleration lacks both with the only possible alternative being 1964 sediments which correlates to nuclear testing fallout which is stored in sediments as carbon 13 is dated from the nuclear bomb testing which Maslin also explores in his paper. The use of superficial sediments is being explored by Reck et al, to try and discover suitable evidence to support the starting date of 1950, however, the only criteria which 1950 ticks is that it points out the starting point in the shift of Global Earth Systems.
Both these dates are contentious and heavily debated as they have social consequences. A later starting starting date of the Anthropocene like 1950, the more diminishing the role colonization and the impacts European nations had on global climate change making it a equity issue as revealed in the Great Acceleration Graphs reinforcing the notion the notion that humanity as a whole contributed to climate change as Steffan et al explores in his study. Using 1610 as the starting date however removes is issue but raises another, being that human climate change is not new and as such we should not be that concerned about it. From my personal view 1610 would be the perfect starting date for the Anthropocene as it fulfills two criteria from the International Commission of Stratigraphy and points out the the unequal damage caused by humans to the climate, putting the burden right on the doorsteps of those who claim to be trying to better the world yet refuse to acknowledge their role in this mess.
Reference list:
Lewis, S.L. and Maslin, M.A., 2015. Defining the anthropocene. Nature, 519(7542), pp.171-180.
Steffen, W., Broadgate, W., Deutsch, L., Gaffney, O. and Ludwig, C., 2015. The trajectory of the Anthropocene: the great acceleration. The Anthropocene Review, 2(1), pp.81-98.
Rech, J.A., Springer, K.B. and Pigati, J.S., 2017. The Great Acceleration and the Disappearing Surficial Geologic Record. GSA Today, 27(11), pp.8-9.
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