Sunday, May 14, 2017

A to Z Reflections 2017

I've been officially retired for seven years and no longer tell people I am a teacher. I don't know that I could manage a classroom anymore. In my thirty plus years teaching, I primarily taught science. For three years, I taught math which was a good break. However, all of my examples were usually using science.

Surprisingly, the A to Z was easy to do. Yes I checked my facts. Memory is not always accurate. I did not keep my promise of consistently posting to this blog during the year after A to Z 2016. A lot of posts are used as lessons for teachers in their classroom and the blog stays busy with visits to them. The most popular blog post I have is the page There is more to dissolving salt than meets the eye.

So, God willing, I will write blog posts each April for the A to Z.

I have a written outline of several short lab books based on materials I created as a teacher. My goal this year is to pull them out and get them ready to be published as print and/or ebooks to be sold. If you are interested please sign up for updates by email and I will let you know when each one is ready. There is no commitment on your part for signing up. And no guarantee on my part to prepare these booklets.  If few indicate an interest, I can't see spending too much time on them.






Sunday, April 30, 2017

Zones

There are a lot of types of Zones on Earth. Climate Zones come to mind. What I find of interest are Global Winds and Global Zones of high or low pressure.

The horse latitudes got their names because this is where horse's died and their bodies were thrown overboard. It is a region of very dry air.

The equator was named the Doldrums because sailors felt tired and listless in the low pressure. Low air pressure usually generate a tired feeling. This is probably why it is so nice to sleep on a rainy day.


Saturday, April 29, 2017

What's in a year?

A year is the time it takes for the Earth to make one revolution around the sun which is 365.2252 days. We compensate for the fraction by having an extra day on February 29th every four years. These are called leap years. Leap years do not occur at the turn of a century unless that century is divisible by 400 like 2000 was. Hence 2000 was a leap year.

What happens in a year depends on how far North or South of the Equator you are. If you live close to the equator, you have a year round summer. As you move North or South, you have seasons. Seasons in the Northern Hemisphere are the opposite of the Southern Hemisphere.

When the Northern Hemisphere has winter, the Southern Hemisphere has summer. Seasons are due to the tilt of the Earth. Some people mistakenly think that the distance from the sun causes seasons. It does not. It is the length of the day. Essentially, the longer the day, the more heat is gained. A longer day produces a shorter night when heat is lost. With more heat gained than lost, you have the heat of summer. The length of the day depends on the tilt of the Earth. Longer days occur when the respective hemisphere of the Earth is tilted toward the sun.

Now why don't you have really hot summers as you move toward the poles. Sunlight hits at an angle and is not as intense as a result. Sort of like pointing a flashlight directly on an object and pointing a flashlight at an angle. The direct beam is stronger. So even though you have excessively long days, the light is not as powerful.

The Earth does move closer to the Sun during the Northern Hemisphere's winter and Southern Hemisphere's summer. This is why the extreme of season's is not as harsh in the Northern Hemisphere as it is in the Southern Hemisphere. The Earth's orbit is elliptical.