Global climate change has already had observable effects on the environment. Glaciers have shrunk, the sea is rising, animal ranges have shifted and there are more intense heart waves.

Scientists have high confidence that global temperatures will continue to rise for decades to come, largely due to greenhouse gases produced by human activities — and the clock is ticking to deal with this. The sooner steps are taken to reduce the carbon in the atmosphere and in the oceans, the better off humanity will be.

Read more from David Martin Davies with Texas Public Radio here.