Why did we see a cooler winter if global warming is occurring?
Jeff Masters has a great article on this, and I highly recommend reading through it for all of the details. There have been a number of talking heads appearing on tv and claiming that, since the winter of 2008 was so cold, global warming is clearly not happening. There have even been some people claiming that we are undergoing global cooling. The United States had it’s 54th coolest winter out of the past 113, so it was about an average year temperature wise for us. Globally, however, this winter was in the top 13% of warmest winters ever.
He also points out the difference between weather and climate, which I think is a very important distinction:
It is important to understand the difference between weather and climate. Climate is what you expect; weather is what you get. What we experience in one particular season or year is “weather”. Weather has a large variation from year to year, with cool seasons and years mixed in with warms ones. “Climate” is the weather measured on scales of tens of years or longer. One cool winter or year is not an indication that the climate is cooling back to normal. The climate is warming, and unless we see a series of several years of cool conditions, this year’s cool winter merely represents a normal fluctuation of the weather.