To The Daily Sun,
Russ Wiles needs a science lesson. According to Phys.org, "Mass extinctions due to rapidly escalating levels of CO2 are recorded since as long as 580 million years ago. As our anthropogenic global emissions of CO2 are rising, at a rate for which no precedence is known from the geological record with the exception of asteroid impacts." It also depends on how fast CO2 rises and which species were alive. Before the Devonian extinction, plants ruled the world in a 4000ppm CO2 concentration. The plants sucked the CO2 out of the air and it fell to 400ppm which caused their extinction. We would die long before 4000ppm.
The Permian-Triassic extinction unfolded for 10,000 years. Equatorial regions became uninhabitable to complex life; 75 percent of land and 90 percent of marine life died. It took ten million years to recover. A recent paper in Paleoworld claimed the average global temperature reached well above 29°C. Today's average is about 15°C. The acidity from the massive amounts of CO2 spewed into the air brought about oceanic acidity that was a global calamity. Phys.org also notes, "massive increases in emission of CO2 from volcanoes, associated with the opening of the Atlantic Ocean in the end-Triassic Period, set off a shift in the state of the climate which caused a global mass extinction of species, eliminating about 34 percent of genera". The Late Devonian, end-Devonian, upper Permian, End-Triassic, End-Jurassic, Cretaceous-Tertiary boundary, Deccan volcanic activity, and the pre-Eocene-Oligocene boundary extinctions are all associated with rapid changes in CO2 concentrations.
In a recent study from the Proceedings of the National Academy of Sciences, during the Paleocene–Eocene Thermal Maximum (PETM) 55 million years ago, CO2 rose extremely fast, increasing the average global temperature 10°C in as short a period as decades. PNAS also claims, "If our Palaeocene estimates are correct, tropical temperatures at the slightly younger PETM could have reached 38–40°C, resulting in widespread equatorial heat-death as recent models and other proxy data have predicted." A recent Nature Geoscience study found humans are spewing carbon into the atmosphere up to 10 times faster than the PETM rate.
Excessive CO2 also has a negative effect on crop nutrients. Worldwide field studies and controlled climate experiments found that high levels of CO2 create hollow plants. There is a significant loss of proteins, iron, and zinc. Billions of people rely on a variety of crops for their nutrition and some crops are hit by significant losses in vital nutrients. According to the NIH, "Iron deficiency ranked ninth among 26 risk factors included in the global burden of disease study and accounted for 841,000 deaths and 35,057,000 disability-adjusted life years lost. Large sections of populations in Africa and Asia are at risk of dietary zinc deficiency and resulting high rates of stunting." Why on Earth would anyone favor growing food with fewer nutrients?