You might be asking yourself: "Is it just me or are summers hotter than ever lately?" Or, "What happened to all those snowy winters we had growing up?" So, is global warming real? The answer is "yes."

Global warming is a scientific consensus that earth's atmosphere is warming in a fundamental and potentially serious way. While the implications of global warming are not precisely clear, the risks of inaction are now too great to ignore.

How do we know the planet is warming?
There is direct and indirect evidence that the earth is getting hotter. We know from direct temperature readings that the average temperature near the earth's surface has risen about 1.5 degrees F since the middle of the 1800s, when measuring and recording temperature became common. By looking at evidence such as tree rings and ancient records of when crops were harvested, scientists can estimate earth's temperature way back in time. The 1.5-degree increase in the past 150 years doesn't sound like much until you compare it with the 850-year period from about 1000 AD to 1850; during that time, the average temperature actually dropped about half a degree, leading to what climate scientists call the "Little Ice Age" — just one of the factors that made life particularly tough for America's first European settlers.

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