Saturday, February 28, 2009
Geography lesson, 27th February 2009Today, our Geography lesson is quite exciting.
Once again, Mr. Heah told us about the better way to study geography. As you all know by now, memorizing is strongly discouraged. But the very fact is that you will still need to sit for exams. So Mr.Heah said the most effective way is to study using your logical/critical thinking (study the Earth as a system) to generate your own knowledge.
After that, we came back to answer the two questions brought by Mr.Heah last lesson
1/Explain the distribution of Earth’s climate
Once again, splitting up the questions to get the main ideas is important. There are several questions you need to think about before you can attempt to find the answer for the main question (as mentioned by Sue-ann in the last post).
However, the most fundamental question you need to think about is what is the Earth’s climate distribution. And I do think that the more important thing is to find out the “how” behind the “what”.
If you look at the World Map of Koppen-Geiger Climate Classification given, you should notice that there is a banding pattern in the climate distribution. This banding pattern is actually along the altitude and is symmetrical along the equator. So, there are some more questions we need to think about before we can reach the final answer.
1. Why is climate different in different regions of the world ( polar, temperate, tropical, temperate, polar )
2. Why is the climate distribution patterned the way it is?
My group came out with several single words to answer those questions such as radiation, heat, shape, tilt, etc. However, we then look at specific features of each type of climate over certain regions. The climate is actually identified to be warmer at equator and cooler as approaching to polar regions. Does it have any link to radiation energy from the Sun? We know that the intensity of radiation has nothing to do with the distance from the Sun to certain region that receives the energy. However, over larger distance, the energy will be diffused and by the time it reaches the surface, it will be less intensive. Here, looking back at our Earth, the equatorial region receives the most intensive radiation from the Sun. Thus, this region is always warmer compared to the polar regions which are farer from the Sun ( by the time radiation reaches those regions, it is less intensive as it has been diffused over space ). Once again, we need to think. Why is it so, why does equatorial region receives most intense radiation from the Sun while polar regions are farer from the Sun, thus get less intense radiation? It is so simple that the answer can be expressed in only one word. It is because of our Earth’s SHAPE. (circular)
So all in all, the answer to a the question actually lies in one key word : SHAPE
2/Why are there seasons?
What are seasons in the very first place?
The most important thing we should know about season is the change of weather (ex, from low to high temperature and vice versa)
Here, we need to look at the climographs given, it is notable that the change occurs in the middle of the year.
Some may ask are the seasons results of changes in the distance from the Earth to the Sun? No, they are actually not.
In our lesson today, we learn that our Earth spins on a tilted axis (this axis is an invisible axis through the center of the Earth) once every 24 hour. That’s why there are day and night.
In addition, the Earth revolves around the Sun once every 365.25 days. As such, the tilt of the Earth causes different regions of the earth to point towards the sun (over specific periods of time). This causes different amounts of sunlight to reach the same surface area of the Earth throughout the year. The different amounts of sunlight lead to different weather at this location
There are seasons because the Earth’s axis of rotation is tilted 23 degrees. In June, northern hemisphere is tilted towards the Sun, so the sunlight has the more direct path to the Earth surface, thus, there are more hours of sunlight during the day. As a result, it is summer in northern hemisphere. Meanwhile, in southern hemisphere, the sunlight has to go a longer path to the surface and the days are shorter in June. So, it is winter in southern hemisphere.
So, basically, looking back at the question and the detailed answer I have written, the main point lies in the word “tilt”
All in all, answers for many questions can be expressed in one word or few. The important thing is that you need to use those few words to generate your own complete answer from what you already know. This is a better way of learning.
So that's about it :)
Chi