Module VI

Essential Question:
How are the Earth, atmosphere and cultures all connected?

One sunny clear day in Rhode Island, I watched two of my closest friends jump out of an airplane while we were flying 10,000 feet above the ground. And then I jumped out after them. We were on a skydiving trip with my school's outdoors club, and I had completed the only prerequisite needed for the jump; signing a piece of paper that said the company would not be held accountable if I failed to survive the experience. Needless to say, my parents were not pleased. Even though my father had the solid backing of his fellow commuting passengers (he had taken a poll and the response was overwhelmingly in his favor) I still jumped out of that plane with only the smallest reservations. Those came in full throttle as my body discovered it was falling through the air and accelerating at 9.80665 meters per second and my vital organs clamored to exit through my mouth. After a few terrifying seconds my falling body reached maximum velocity, and then the experience became quite pleasant. The ground was so far away that I felt like I was flying instead of falling, and by spreading my arms and shifting my weight I could traverse the sky. A great example of this fluid nature of the atmosphere can be seen in this National Geographic video on Youtube that includes a skydiver "surfing".

A few years ago I was able to experience this fluid nature of our atmosphere under much more comfortable conditions. During a family reunion in New Mexico, my sister, mother, and I rented a hot air balloon, and let the wind carry us along. The only thing we could control was our altitude, which we did to find the perfect wind speed to leisurely float over rooftops and down a river valley. Another balloon took off just after us, and it was amazing to watch the different paths we took through the sky, due to the slight differences in the wind direction and speed at our respective altitudes.

Dipping down into the river in our hot air balloon - C. Walker

Using Google Earth's weather layer I captured these images of the weather above both the North Atlantic and Pacific Oceans. Looking at them it is easy to see the fluid nature of our atmosphere. The prevalent wind patterns are also visible as they head up from the equator towards the Arctic.


The 8th grade science curriculum in Achorage doesn't get into the atmosphere and weather, and I never took any courses specifically on those subjects in college. The ExploreAlaska blog VI is a great resource for educators like me who know the basics but need a clear, informative collection of information and teaching tools to help students learn how the atmosphere works.

One TD resource from the blog enables one to see the vertical structure of the atmosphere and to learn how density and pressure decrease with altitude, while the air temperature is less consistent ad defines the four distinct atmospheric layers. A fun way to teach about the layers of the atmosphere in the science classroom would be to make the different layers out of different colors of jello, and have students insert appropriate objects (mountains, planes, clouds, space shuttles) into the appropriate layers. Another TD animation compares and contrasts warm and cold air fronts, and helped me to understand why it is so cold down on the ground during a warm air front. This could be demonstrated by mixing colored water of different temperatures.

I learned that convection in the atmosphere is very similar to that in liquids, and that the motion of rising and falling gasses due to their temperature, humidity, and density creates winds. The ocean plays a large role in this by heating the troposphere directly above it, and evaporation from the ocean adds to the humidity of the air. Winds are directed eastward by Earth's rotation and the uneven heating of Earth's surface. These winds are fastest at high altitudes due to the more extreme pressure differences found there and these large masses of moving air are called jet streams. The youtube video Global Circulation shows explains the poleward movement of wind from the equator due to atmospheric temperature and pressure.

All of this is very interesting and helps explain the weather we see around us, but the information in the blog that I found to be most intriguing was that on how global pollution rides the wind up from the equator to the polar regions. I had a faint prior understanding of this phenomenon, and I knew that there is a similar process going on with the ocean currents, but I had no idea of the extreme time scale on which it happens. Pollution from factories and power plants in Europe can make it up to the Arctic in a matter of days and within a few weeks it enters the food chain. Arctic organisms exposed to polluted air and water absorb the chemicals (heavy metals and persistent organic pollutants - POPs) and as plants and animals are successively eaten the toxins are accumulated in body fats and the effects increase as you go up the food chain, in a process known as bio- accumulation. This process is extremely dangerous for nursing mammals due to the fact that heavy metals and POPs accumulate in breast milk. This can lead to high infant mortality, low infant brith weight, and other health risks.

Information like this definitely fits into my 8th grade science curriculum, and makes a direct impact on the lives of my students and the animals around them. I already teach about bioaccumulation and its impacts on our ecosystem, but now I can teach my students how the chemicals arrive in our ecosystem in the first place, and where they come from. Tools like the Google Earth weather layer will make this very easy for them to see and understand. At the moment the process of pollutants from industrialized countries being deposited in the Arctic is being studied by the NASA ARCTAS mission and is not well known or understood, but as students start to become aware, society is bound to follow. I don't believe that societies will hold themselves accountable for their pollution that is rafted elsewhere by their own accord. It will have to be dealt with something akin to the current day international climate talks and agreements. In order for this to happen, we need to get the word out to as many people as possible, and as teachers we have a great platform from which to do so.