"The main concern is that we can’t really predict how ecosystems and human society will respond to climate change," say scientists who worry carbon levels could overwhelm natural systems by 2200. "The global climate is more than likely to slip into an unpredictable state with unknown consequences for human societies if carbon dioxide emissions continue on their present course, a survey of leading climate scientists has found," reports the Independent. "Almost all of the leading researchers who took part in a detailed analysis of their expert opinion believe that high levels of greenhouse gases will cause a fundamental shift in the global climate system — a tipping point — with potentially far-reaching consequences."