"Global warming" articles are again in the news as summer heat records collapse and Ventura County swelters through weeks of 100-degree temperatures.
Although it may feel as though the Earth is getting hotter, global warming is an inaccurate description of what is happening to our weather patterns. A better term is "global climate change." Global climate change means that parts of the world will experience more severe winters along with hotter summers; other places will have more and stronger hurricanes and altered growing seasons.
As an environmental sociologist, I study the way that humans shape their environment and how the environment, in turn, shapes human societies. One example of the reciprocal relationship between humans and the environment is global climate change.
A warming trend that began about 1890 has increased the Earth's temperature by about 1 degree Fahrenheit during the last century and is expected to increase world temperatures by 2 to 6.5 degrees F in the next century. A few degrees increase in average global temperatures doesn't sound too serious, but the global average temperature was only 5.5 to 9 degrees F cooler than it is today during the last ice age, when glaciers covered most of Europe.
Global climate change is occurring because of a buildup in the atmosphere of the "greenhouse gasses": carbon dioxide, methane, nitrous oxide and chlorofluorocarbons. These gasses trap the sun's energy as it is reflected from the surface of the Earth.
The "natural" greenhouse effect is what keeps the planet warm. It is created by the byproducts of the breathing cycle of all living organisms and by volcanoes, decomposing plants, water vapor and plant and animal waste. Human activities have intensified the natural greenhouse effect, through our consumption of fossil fuels and other greenhouse-gas-producing products.
The most serious consequence of global climate change may be sea-level rise. Global warming will cause the oceans to rise because seawater expands when it is heated, and glaciers and polar ice caps will melt, increasing the volume of seas.
How will global climate change affect Ventura County?
First, Ventura's coastline is at risk to sea-level rise because, unlike other California coastal counties, Ventura's coastal zone is relatively flat and low. About 15,000 years ago, the sea level was about 91 meters lower than it is today. In Ventura County, sea level has been rising at the rate of one to two millimeters per year, or one-tenth to one-quarter of a meter over the past 100 years, and may rise more than half a meter (about 20 inches) over the next 100 years.
