Climate change questions

Recently, I attended a program about “climate change.” Ever since, I have been wondering: What is this thing that is going to be changing?

In the simplest sense, climate is the average weather conditions observed for a given geographic location over many years.

Weather includes such things as precipitation (measurable rain, sleet and snow), temperature (highs and lows), as well as wind (speed and direction). The weather in a place is determined by the pressure and moisture of the air. Weather is influenced by large-scale things such as the jet stream and by local factors such as pavement or agriculture.

But back to climate.

Climate is influenced by the latitude, altitude, vegetation cover, and even the presence of mountains or large bodies of water such as oceans or large lakes (like Lake Michigan).

Watching the weather reports recently, I noticed that northwest Indiana had about a foot of snow on November 18th. This is known as “lake effect” snow because it is influenced by the proximity of Lake Michigan. Towns just a few miles away had no snow – because they were just that much further from the lake and it’s effects.

So, what’s the big deal about a changing climate?

Consider this: the reason that the Midwest is known as the “breadbasket of the world” is because of the unique combination of climate and soil that is found here. The cornbelt was once a vast tallgrass prairie, which is why the soils are so productive for growing crops.

But, it isn’t just the soil that makes the Midwest a great location for agricultural production, it is also the climate. Simply put, in the Midwest it rains during the growing season in a quantity needed to grow most crops without irrigation. This phenomenon of rich soil and ideal climate is unique when one looks across the globe.

What happens, however, if – when – the climate changes?

What if the growing season becomes longer or shorter than it is today? What if the average rainfall increases or decreases by a significant amount? What if the rainfall occurs during a different time of the year – earlier in the year or later, rather than primarily during the growing season? What will happen to food production if average temperatures increase?

What happens to the Midwest agricultural system if several of these things happen at the same time?

The short answer is: no one knows for sure.

But a clue can be found when one looks at what happens during a long, hot, dry summer. Crops die. Crop yields are lower. Some farmers irrigate with well water to supplement the scant rainfall. The government pays farmers something for the losses to help them get through the crisis, but folks know that a drought is a unique weather event, so no one panics.

When the next year arrives, the rains return and all is right again.

What if the rain doesn’t return the year after the drought? What if the rain comes in April and October, but not in June or July?

Again, no one knows for sure, but I have the feeling that if – when – this region starts to experience a changing climate, residents will adapt. Keep in mind that climate is the average weather over a period of time, so let’s pay close attention to changes in those averages, and take steps to be prepared.

Thinking about light pollution

Let’s quickly review the consequences of light pollution.

Direct glare caused by excess or inappropriate lighting makes it harder to see. Think of how difficult it is to see when an on-coming car fails to dim its brights. Bright light shining directly into the eye causes the pupil to contract, and it can take up to an hour for the eye to recover. While recovering, nighttime vision is greatly impaired. It is helpful to keep in mind that the eye always adapts to the brightest object in the field of view. When the brightest object is the light fixture itself this causes everything else to appear darker than it truly is.

Migrating birds are disoriented by bright lights. Hundreds of species of birds migrate at night. But brightly lit structures, or spot lights aimed to the sky, can confuse the birds, drawing them towards the light, often resulting in collision with buildings, towers or other tall, illuminated objects.

Energy is wasted. By having bright lights spreading light pollution all night long, billions of dollars are wasted each year by homeowners and businesses.

Neighbors are annoyed. A bright light shining into the bedroom at night is the classic example of neighborhood light pollution.

And, light pollution makes it hard to see the stars in the night sky.

There are several simple, inexpensive steps that everyone can take to reduce light pollution.

First, a homeowner can stand at the edge of her property and check to see if she can see any lightbulbs. If so, then she is contributing to light pollution in her neighborhood, but a few simple changes will fix the problem.

Shield the bulb/point floodlights towards the ground. By directing light towards the objects it’s intended to illuminate, people will avoid something called “light trespass,” or light leaving the property and trespassing onto someone else’s. Sensible lighting also means that lights are directed towards the ground, not up into the sky or out into space.

Reduce the wattage. A 40 watt incandescent (or 11 watt compact fluorescent) bulb is bright enough for a front porch light.

Attach a motion sensor. This is by far the best application of security lighting because when a light turns on suddenly it immediately attracts the attention of everyone within its field of view. Police and security personnel are drawn to investigate an area usually dark where sensors have triggered the lighting.

Lights off after 10pm. Most people are at home and in bed (or getting ready for bed) by 10pm, making “decorative” lighting an unnecessary waste of energy. This is also the time when excessive lighting is most likely to affect migrating birds.

Talk to the neighbors. After a homeowner gets his or her lighting in order, it is time to approach any neighbors who are causing light pollution. Explaining the steps taken at ones own property, and emphasizing the energy savings is probably the best way to start the conversation.

Maybe the neighborhood can hold a star gazing party once the light pollution is gone!