Humankind is emitting carbon 10 times faster than at any time since the extinction of the dinosaurs.
(April 4th, 2016, OTTAWA, ON.) Scientists have to go back 56 million years to find a rate of carbon emissions anywhere near comparable to present-day rates.
New research published in the journal Nature Geoscience indicates that only once during the past 66 million years has as much carbon been emitted into the atmosphere as is now occurring through human activities. The other great emission, whose causes are still debated, occurred 56 million years ago — 10 million years after the extinction of the dinosaurs — when atmospheric carbon dioxide levels spiked during the Paleocene-Eocene Thermal Maximum (PETM).
This caused temperature increases of up to 5 degrees Celsius over a few thousand years, leading to a major warming event that lasted over 100,000 years and led to major die-offs of some marine organisms due to ocean acidification.
Between 2,000 and 4,500 billion tons of carbon entered the atmosphere during the PETM, but this occurred over some 4,000 years, averaging about one billion tons a year.
In contrast, scientists estimate that 10 billion tonnes of carbon are being released into the atmosphere every year, due largely to fossil fuel burning and other human activity.
Accordingly, scientists are sounding an alarm. “Our carbon release rate is unprecedented over such a long time period in Earth’s history, [that] it means that we have effectively entered a ‘no-analogue’ state,” said Prof. Richard Zeebe, at the University of Hawaii, who led the new work. “The present and future rate of climate change and ocean acidification is too fast for many species to adapt, which is likely to result in widespread future extinctions.”
A 2009 study of the relationship between population growth and global warming determined that the “carbon legacy” of just one child can produce 20 times more greenhouse gas than a person could save by driving a high-mileage car, recycling, using energy-efficient appliances and light bulbs, etc. Each child born in the United States (and likely in Canada) will add as much as 9,441 metric tons of carbon dioxide to the carbon legacy of an average parent.
Population Institute Canada believes that fast-growing human numbers (one million every five days) and high rates of consumption will inevitably exacerbate the rate of greenhouse gas emissions. PIC advocates for smaller, more sustainable families through access to voluntary family planning to ensure a better quality of life for all, and to reduce demands on the natural world that are overwhelming efforts to protect the biosphere.