Transcript for World's Top Scientists Issue Climate Warning
urgent new warning from some of the world's top scientists. And this is their message. The unforgiving winter, those ferocious fires, the extreme weather we've all endured together could indeed be a herald of a new Normal, climate change. They say it's a reality humans helped create on the planet and ABC's senior national correspondent Jim Avila now has this news wakeup call about a warming Earth. Reporter: It's not the future, it's here. Bigger storms, this one last night in Hong Kong flodding out a shopping mall. And today's ominous report, blaming the increase in extreme weather on global warming. Here in America, more wildfries, intense burns like this one in Colorado. It was awful. To watch it burn down. Reporter: Devastating drought in thecan west. The result, higher food prices for all. The nation's coastline under pressure from rising seas. Lower Manhattan and the Jersey shore underwater due to hurricane sandy. Last year alone, the U.S. Suffered seven weather disaster events, costing the country $7 billion and 109 lives. The global warming that has already occurred is already having impacts. Reporter: And while global warming is easiest to see at the poles, this new report by a united nations science panel says there is no more debate. Global warming is real, here now, wreaking havoc worldwide and is caused by humans. It is consistent with human activities, particularly the emissions of greenhouse gases to the atmosphere. Reporter: America is making semiprogress in cutting back on emissions. Unfortunately, India and China are not. Temperatures now rising three to five degrees worldwide in these yellow and red areas since the 1950s. In fact, despite America's most recent rough winter, around the globe, 2013 was one of the warmest years ever. Jim Avila, ABC news, Washington.
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