Perhaps There Are Just Too Many Humans
David Attenborough: A Life on Our Planet has captured the evolution of our planet, which has been heavily taxed since the early 20th century, as technology advanced and human population grew rapidly (from 2 billion in 1930 to nearly 8 billion in 2020). Can the Earth sustain the growing human population and absorb our carbon emission?
Paleoclimate reconstructions indicate that the Earth’s temperature had been like a roller coaster going through cold (glacial) and warm (interglacial) periods. This is due to changes in the Earth’s orbital geometry (Milankovitch Cycles) that leads to variations in intensity and latitudinal distribution of incoming solar radiation. However, the rapid warming of the 20th century cannot be explained by just natural factors.
The IPCC (the United Nations Intergovernmental Panel on Climate Change) 5th Assessment Report showed, by comparing reconstruction data with instrumental data, that the warming rate over the last century is at least 10 times faster than that during the inception of the present interglacial period. If the world continues on the high greenhouse gas concentration pathway, the warming rate of global temperature will further increase to 50 times faster and the Earth will be 3.7℃ higher than the average of 1986–2005 by the end of the 21st century!
Human influence on the climate is clear. Last month (March 2021), the UK Met Office reported that the atmospheric carbon dioxide concentrations has increased by 50% than before the industrial revolution. Human-caused carbon emissions have postponed the next ice age by 100,000 years as pointed out by a study published in the journal Nature. Human is making significant impact on the Earth’s climate and ecosystems that can justify the establishment of a geological epoch — “Anthropocene”.
Perhaps there are just too many humans…
