November 3, 2011 - By Meghan Walla-Murphy
Source: TOPANGA MESSENGER - Santa Monica Mountains News and Arts
(http://www.topangamessenger.com/story_detail.php?ArticleID=4790)
People once doubted that gravity existed. Galileo was charged with heresy and subjected to house arrest for his belief that the earth revolved around the sun. Evolution was and still is contested as a mere trend that will pass.
Similarly, a large percentage of people in the United States believe that climate change, also referred to as global warming, has been manufactured by the media. Or, as assemblymember Betsy Butler stated at a joint informational climate change hearing on October 20, she regularly encounters people who do not believe climate change is occurring; we are simply between ice ages, they say.
Even in the face of staggering statistics, unprecedented fluxes in weather patterns and rising annual temperatures, many still doubt that global warming is really happening. The reality is that the last 150 years have seen an increase in some greenhouse gases but the last 50 years have seen a tremendous spike in carbon dioxide emissions due to the burning of fossil fuels.
Climate Change is Complex
Perhaps the apathy to acknowledge that we are headed for a brick wall at astonishing speed without a proper safety belt stems from the complex nature of climate change.
In the past, climate change referred to fluctuations in temperatures that resulted from the earth’s natural processes, e.g., ice ages or El Nino. Currently though, climate change is often used synonymously with anthropogenic global warming. Yet global warming only refers to the increase of temperature on the earth’s surface. The term climate change is more inclusive, encompassing increased temperatures as well as all the consequences of increasing greenhouse gases.
To understand greenhouse gases, one must imagine the earth and its atmosphere as a giant greenhouse, where gases such as water, nitrous oxide, carbon dioxide, methane and human manufactured gases act like a layer of glass. These greenhouse gasses allow sunlight into the earth’s atmosphere where some is absorbed by the earth. The energy not absorbed by the earth is then reflected back into the atmosphere where it is either stored or released into space. In a balanced system the amount of heat received from the sun should be roughly the same amount of heat radiated back into space. Such a working system leaves the earth’s temperature relatively constant over long periods of time.
U.S. Largest Contributor of Greenhouse Gases
Normally, the earth metabolizes carbon emissions through multiple processes known as the carbon cycle. One example of a carbon cycle process is the consumption of carbon dioxide by photosynthetic plants. In the past the earth neutralized 6.1 billion metric tons of human-made carbon dioxide emissions. Unfortunately humans currently create 3.2 billion metric tons more than the 6.1 billion tons the earth can deal with naturally. The United States is the largest contributor of greenhouse gases in the world.
This imbalance between emissions and absorption essentially creates a thicker greenhouse “glass” that continues to allow sunlight in, but does not allow excess heat to escape, which results in an increase in the earth’s average temperature.
The Reality of Rising Sea Levels
Temperature change is not the only consequence of excess greenhouse gases. Another effect of climate change includes a rise in sea levels. While this does not immediately affect Californians, 50-year projections show our sandy beaches eroded and our flat seaside communities like Marina Del Rey underwater. Property lines will change, but so will the salinity of our ground water. Fresh water, essential to our coastal riparian ecosystems, will become brackish and many of our native species will succumb to habitat loss. The quality of water for people who have wells sunk into the coastal water table will be undrinkable.
Another consequence of climate change will be dramatic floods and droughts. Projections show an intensifying of weather patterns. Although California will receive the same approximate rainfall, the rain will come in deluges of massive storms that will create floods rather than rain scattered over a season. This weather pattern that we are already seeing means greater runoff, less water storage in the land and more erosion. In addition, Sierra snowpack, responsible for a large percentage of California’s annual water use, will melt earlier and faster, again causing storage-usage problems in the future.
Sitting opposite the floods will be tremendous drought. Areas in California that are already dry will experience more days and weeks over 100 degrees Fahrenheit. What little rain that does fall in these areas will be evaporated more quickly due to increased temperatures.
And this is only the tip of the proverbial iceberg that is melting. Many other significant changes will impact life as we experience it today. But unlike those who challenged Newton, Galileo or Darwin, to disbelieve that climate change exists condemns not only your own existence but also the entirety of the earth’s living communities.
In order to change this outcome we must each accept the role we play in climate change and begin, today, to alter our daily habits.
The state of California has already begun to do this through Cal-Adapt, a product of the Public Interest Energy Research (PIER) program. Visit: http://cal-adapt.org/ to better understand climate change and how you can create positive human change
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