Sunday's editorial, "Time's up for climate change deniers," left out something very important: overpopulation. As Walt Kelly's cartoon character Pogo said, "We have met the enemy, and he is us."

Climate change, like many other problems — flooding, water shortages, pollution, hunger, deforestation, mass extinctions, infrastructure deterioration, traffic jams, crowded beaches — is related to overpopulation.

According to the nonprofit organization Population Connection, Earth accumulated a billion of “us” by 1804. By 1927, 123 years later, “us” doubled to 2 billion. We redoubled to 4 billion by 1974. We grew another 2 billion the next 25 years. Between 1999 and 2011 — just 12 years — our population grew another full billion.

Between 1927 and 2011 — despite mass loss of life caused by such events as World War II, the AIDS epidemic and ethnic cleansing including the Nazi death camps — world population grew exponentially. What if that continued?

How can world leaders hope to fix problems such as climate change if they and the media fail to acknowledge and deal with overpopulation, the problem’s source?

Landon McDonald, Gillette