Have you noticed, as I have, that in this fall and winter of 2010 we have had and are having "unusual weather events" with increasing frequency? Here are some examples:
Right now, there is a very unusual deep freeze covering about half of the geographical US and extending all the way down to Florida, where it is endangering the citrus crop. This deep freeze is accompanied by extensive snowfall in the midwestern states. Meteorologists admit that a cold wave like this so early in the winter season is unusual. In Minnesota, meteorologist say that it is the most powerful storm to hit Minnesota in "a long time." Within the past 2 weeks there was 3 feet of snow In Buffalo NY in a period of (I think) 48 hours, and 16 inches of snow in northwest Indiana.
There have been 2 recent incidents of cruise ships caught in intense storms causing huge waves that tossed cabin contents and people around in their rooms for as long as 2 days. One occured South of Cape Horn involving a ship returning from an Antarctic cruise, which experienced 45-foot waves. The other involved a ship in the eastern Mediterranean Sea in which there were hurricane force winds and huge waves. The latter has been called "unprecedented."
Over the past few years there have been increasing numbers of increasingly strong tornadoes, not only in the usual places (midwest) but in unusual places (like Arizona). Similarly, hurricanes seem to be increasing in number and strength. The worst year was 2005 when there were 27 named tropical storms (a bit more than our alphabet can handle). Katrina hit in August, then Rita in September, then Wilma hit in October. All were very destructive storms hitting various Caribbean areas. We all know the Katrina story.
Over the last few winters, large snowstorms have been happening in the northwest, where conditions are usually pretty mild in winter.
There are persistent droughts in large regions of Africa (Sahel region in particular), while in other places (recently Pakistan) there are deluges of rain and floods.
In 2003, a long heat wave in Europe resulted in the deaths of 30,000 people (this number varies according to where you read it, so I have picked the smallest estimate of deaths)
The decade of the 1990s was the hottest on record. How about the decade of the 2000s?
In Alaska, average yearly temperatures have risen 5 degrees Fahrenheit in summer and 10 degrees Fahrenheit in winter since the 1970s. Wonder what effect this has on the livlihoods of Alaskans?
California has experienced a very large number of very destructive forest fires. This is a result of drying out of the forests, which is in turn weather related.
Huge swaths of mountain forest in Colorado, Utah, Wyoming have been devastated by the pine bark beetle (Cathryn and I saw this during an RV trip this past summer-both campgrounds in Rocky Mountain National Park looked like RV parking lots full of stumps). This also is weather related in two ways. First, the trees had dried out enough to make a comfortable temporary home for the beetles. Second, the reproductive effectiveness of the beetles has been enhanced by warmer average temperatures in the mountain regions.
What is responsible for this escalation in severe and unusual weather? Actually, this is one of the predicted (as early as the 1980s) consequences of the gradual and persistent increase in average global temperature caused by the accumulation of greenhouse gases in the atmosphere. This is called global warming--you all know about it. Many of you don't "believe in it", asking things like "How is a cold wave in the midwest consistent with global warming?" The answer is to be found in understanding the difference between weather (a daily, local phenomenon) and climate (average weather over the entire globe
and over a relatively long period of time, usually a year or a decade).Global warming refers to the average temperature of the surface of the earth over, say, the period of a year. Weather in a given location varies widely from season to season, even day to day, as it always has, and is unpredictable. Climate, on the other hand, is quite predictable, precisely because it is an average of weather over a long period of time. You can read about this.
Rising average temperature has consequences, many consequences. One of these is that oceans warm up. This of course means more rapid evaporation of water from the oceans and soils. This means more water vapor in the atmosphere. This means more precipitation (rain, snow, sleet, hail). This also means more intense hurricanes and tornadoes, both of which gain energy from the heat released when water vapor condenses. Larger amounts of water vapor mean more available heat to fuel storms. It all ties together in a way that is quite logical at the same time that it is quite scary. Even if we completely stopped producing CO2 right now, average global temperature will continue to increase gradually for at least a century, due to the time lag involved in the huge oceans to heat up to the point that the earth gives up energy to space at the same rate that it receives it from the sun. This means things are going to get worse weather-wise even if we stop CO2 production cold right now. As the oceans warm up, they will release come of the CO2 that is now dissolved in them (gases get less soluble in water at higher temperture), exacerbating the greenhouse effect. This is called a positive feedback (phenomenon A causes phenomenon B causes phenomenon C which enhances phenomenon A).
Just more food for thought as you continue to pump CO2 into the atmosphere by driving (very bad), using your cell phone, using your computer, turning on a light, running your washing machine and your dryer (very bad), your refrigerator, your microwave, your oven, your stove (very bad), your toaster, your power tools, your TV, your sound system, your radio, your shower, your lawn mower, your dishwasher, your flashlite, your motorcycle, your automatic garage door, your vacuum cleaner (very bad), your coffeemaker, your coffee bean grinder, your electric carving knife, your blender, your toaster oven, your ipad, your kindle, your...
Is there anything we can do that does not make our situation worse?