We Could Have Discovered Climate Change As Early As the 1940s if We Had Just Looked

The signs of global warming are hitting us over the head today -- if you'll remember, the fire and drought -ridden summer of 2015 was the also hottest in recorded history -- but how long has our planet actually been feeling the heat? In parts of the tropics, anthropogenic climate change has been tinkering with the thermometer since the 1940s.