Recently The Union printed a letter in the Other Voices section titled, "Don't be fooled by climate change."The writer couldn't have been more wrong. Global warming may be far worse than any of us think. The greatest environmental challenge facing the earth is climate change. Global climate change is rapidly approaching a point when the world will be irreversibly hotter, no matter what actions are taken to reduce greenhouse gas emissions. There is now evidence that global warming is driving evolution and extinction. There is overwhelming evidence that species are changing their distributions due to climate change. For about the …