Reuters: A temperature goal set by almost 200 governments as the limit for global warming is a poor guide to the planet's health and should be ditched, a study published in the journal Nature said on Wednesday. The world's environment ministers agreed in 2010 to cap a rise in average surface temperatures at 2 degrees Celsius (3.6 Fahrenheit) above pre-industrial times as the yardstick to avoid more floods, heat waves, droughts and rising sea levels. "Politically and scientifically, the 2 degree C goal is...