For years, scientists have been urging a world-wide response to the threat of climate change. They say unless countries alter their ways of living and thinking, we are destined to see a dangerous rise in global temperatures.

A number of countries and companies have set goals to reduce their emissions to become carbon-neutral.

Currently there are four countries competing to become the first completely carbon-neutral country in the world. New Zealand, Norway, Iceland and Costa Rica all have public policies aimed at that goal. Costa Rica is the only country in the Americas that has formally pledged to go zero-carbon.

Costa Rica’s new president stands firmly behind the country’s quest to become carbon-neutral. And using clean energy sources for transportation – like hydrogen – is a key goal.

Correspondent Harris Whitbeck reports from San Jose, Costa Rica.