April 8, 2021
Climate Change Weekly #393
Feeding the world’s hungry ranks among the greatest difficulties humankind has experienced throughout its history. With the Earth’s population expected to top nine billion between 2050 and 2100 (before starting a rapid decline), this challenge will likely worsen in coming decades unless people embrace increases in carbon dioxide and genetic engineering of crops.
Far from being an impediment to continued human existence, rising levels of carbon dioxide are part of the solution to world hunger.
The fact is, most plant life arose when carbon dioxide levels were much higher than they are today. During the most recent ice age, atmospheric carbon dioxide levels fell to dangerously low levels: just 180 parts per million (ppm). Plants begin to die when carbon dioxide is at or below 150 ppm, because at that point they are unable to use sunlight to photosynthesize food from carbon dioxide and water. After Earth emerged from the most recent ice age, carbon dioxide levels rebounded to approximately 280 ppm, still far below the levels existing when plant life began to colonize the land.