"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.
Rising sea level would affect the Ventura County coastal zone in several ways. It would intensify storm surges, resulting in accelerated beach erosion and shoreline recession. It would reduce fresh water supplies, wetlands, dunes and protective shorelines, and it would release soil-bound chemicals from agricultural land. It could result in the loss of natural habitats such as the Ormond Beach wetland.
Natural ecosystems are not the only potential casualties of rising sea levels. The Ventura coastal zone contains high-density housing, major hotel complexes, three harbors and two Navy bases at elevations less than 10 feet above sea level, excluding high tide measurements.
Ventura's agricultural lands would be impacted by saltwater inundation that could further reduce available cropland and force homeowners to relocate. Localized relocations would drive up real estate prices of previously less-valued real estate markets.
Finally, public utility and transportation authorities would have to take eroding land bases into consideration when planning for highway repairs or improvement.
Storm anomalies and significant beach and shore retreat are already in evidence in the Ventura County coastal zone. Sand mining has left the sand resources of the Santa Clara River delta depleted and will result in reduction of southern beaches. Increases in sea level could result in additional vulnerability of the Ventura coastline to storm surge impacts.
Longer and hotter summers like the one we are currently enduring will send more people to Ventura beaches--but will there be beaches?
It's time we begin to live with the environment rather than modify the environment to meet human needs. Changes in coastal land-use policies are needed to ensure the continued existence of Ventura's valuable beaches.