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Durango Herald Environment Population

Drive Gently

We Americans are in love with our cars. We use them for transportation, courtship and entertainment. They mean power, independence and beauty. Unfortunately, they deplete fossil fuels and cause pollution. The car, which has helped to form American culture, may also speed its decay.

Remember, environmental deterioration is determined both by the number of people and by the resources each person uses. Americans tend to use much more than our share of resources. Therefore, we ought to limit the assets we consume as well as limit the growth of our population.

When gasoline explodes in a car’s engine, it releases water vapor and carbon dioxide. Although harmless in the shortrun, the gradual buildup of CO2 over the past century has been a major cause of global warming. Since few people are willing to give up driving completely, we should look at ways to limit its bad effects.

There are many steps that you can take to decrease your use of gasoline. This can begin when choosing a place to live. A home close to work will save time, money and gas in commuting. When buying a car, give thought to saving fuel. Don’t get the largest vehicle that you will ever need, but plan on the most practical one that will serve most of your needs. For those rare trips you can borrow or rent a larger vehicle. Look at the mileage figures and think of long-term savings.

You can minimize the amount that you need to drive. Plan errands with efficiency in mind. Drive to a central parking lot then walk to each store. Work at home when possible to save a lot of gas.

Biking and walking are the ideal. Remember, the bicycle is the most efficient way to transport a person—and always wear your helmet! Not only do walking and biking reduce fossil fuel use, they are also excellent exercise.

Public transportation is much more efficient than everyone driving in separate vehicles. Many cities have inexpensive conveyances that allow efficient use of time by reading or working while travelling. Carpooling is another way of increasing efficiency, both of your time and of the Earth’s resources.

When you do need to drive, there are actions you can take to reduce your fuel use. First of all, don’t warm up the engine. It doesn’t need to be warmed up, and doing so wastes gas and pollutes the air. When you stop for more than a minute, like at a drive-in window, turn off the engine. In the summer, use the air conditioner for higher-speed driving only. You can usually stay cool at lower speeds by opening the windows.

Driving smoothly really helps increase efficiency. Avoid rapid starts and sudden stops—both take a toll on your mileage. The less you need to use the brakes the more efficiently you are driving. It helps to anticipate traffic lights and stop signs so you can speed up and slow down more gradually to match traffic and signals.

At the pump select the lowest octane gas that is safe for your car. Higher than necessary octane won’t give you better performance. Be careful to not spill any gas. A gallon spilled leaks as much hydrocarbons into the atmosphere as driving 7500 miles.

Maintenance also affects your vehicle’s efficiency. Probably most important is to keep tires inflated properly. To get the most out of every gallon of gas be sure that the engine is properly tuned and has clean air and fuel filters. Finally, recycle all used oil, batteries and tires. Improper disposal hurts us all—did you know that the leading source of oil pollution of our waterways is used motor oil?

What does the future hold? Toyota and Honda already sell cars with wonderful mileage. The Prius and Insight both use light construction, smooth aerodynamic design and an innovative hybrid power train. A relatively small gas engine turns a generator. Electricity powers motors connected to the wheels. A small bank of batteries provides a power reservoir for bursts of speed. Much of the energy from braking can be stored in the batteries for later use. This hybrid technology and other improvements promise to decrease our reliance on fossil fuels.

It is hard to imagine life without our vehicles. We should use them carefully, however, remembering that they turn valuable resources into pollution. Driving more efficiently will allow more people to live on the planet with less impact.

© Richard Grossman MD, 2005

Categories
Environment Global Climate Change Population

Sweat Over Global Warming

“Some say the world will end in fire, some say in ice.”
– Robert Frost

Last month I wrote about positive feedback loops. Another name for these loops is “vicious circles”. Their end result is often very destructive since a positive feedback loop can run out of control quickly.
An example of a positive feedback loop we all know is a sound system that squeals when the volume is turned up too high. Another example is what is happening to the ice pack in Greenland and to many glaciers. Being light in color, snow and ice reflect most of the sun’s warmth. As the climate heats up, snow and ice melt exposing rock and soil underneath. Because of the darker color, they absorb more of the solar radiation which heats them up more, and so on.
In last month’s article I described six other positive feedback loops that all work to increase the planet’s temperature. Several involve the greenhouse gases, carbon dioxide and methane. The sky-rocketing level of CO2 is the result of human activity—from our profuse use of fossil fuels.
Thanks to careful monitoring since 1958, we know that the CO2 in the atmosphere has increased from 315 parts per million (ppm) to 380. The rate of increase of CO2 is even faster now than back in the 1950s. Furthermore, historic levels are significantly higher than any for the prior 650,000 years! How can we determine CO2 in the atmosphere from so long ago? Scientists measured the gas content of bubbles in Antarctic ice going back that far. Methane, 24 times as powerful in keeping in the sun’s heat, is also rising dramatically.
The planet’s temperature back in prehistory has also been estimated using isotopes of oxygen. If you compare a graph of those temperatures and a graph of CO2 concentrations, there is a strong correlation. It seems that the planet gets a fever whenever the CO2 level goes up! The greenhouse effect of CO2 (and methane) is the cause of this temperature rise.
Our time in the history of the earth is without precedent so no one can predict with certainty what the future will hold. Although our species has been around for a hundred thousand years, we have only been using fossil fuels in a big way for about 250 years. Never before has humanity faced the possibility that it has changed the planet’s climate so radically.
Some predictions made by scientists are frightening. One model suggests that the climate will change even more drastically when atmospheric CO2 reaches 500 ppm. At the current rate of increase this will happen before the year 2100. Negative feedback systems now functioning limit warming. For example, as trees burn and release CO2, the smoke shades and decreases heat absorption. At 500 ppm those systems will be totally overwhelmed and the temperature will rise even more rapidly. Quite simply, we will bake. The world as we know it will no longer exist.
The prospect in the short run is also terrifying. If the average temperature rises just five degrees Celsius (9 degrees Fahrenheit), most of the temperate parts of the planet will become desert. This might happen about 2050, according to preliminary information from the Intergovernmental Panel on Climate Change. Not only will the climate become hotter, precipitation will diminish through much of the world. The subarctic, currently too cold to grow much, will become the most productive area in this future. There will be much less agricultural land in this scenario, and the growing season will be short. The saddest part of this model is that this rise in temperature will prove fatal to many millions of people—perhaps even billions. They will starve to death.
Unless we change our course radically, the future looks frighteningly bleak. Fortunately I will be dead before the full consequences of global warming hit, but I cannot help but think of what will happen to my granddaughter—and millions of other youngsters. This calamity is largely a consequence of my generation and others of the 20th century. We reproduced faster than in any other era of human history. And we enjoyed the pleasures of fossil fuel to the hilt. Unfortunately it is not we who will suffer the consequences, but our offspring. Our iniquity will go beyond the third and fourth generations.
It may already be too late to prevent this climate hell, but that doesn’t mean that we shouldn’t try. Averting global climate change will be the subject of next month’s article.

© Richard Grossman MD, 2006