Sunday, November 25, 2012

Summary of notes

Solar radiation from the sun controls weather on earth in a variety of ways. Solar radiation, for example, provides 100% of earth's energy budget. This energy given by the sun then is absorbed and heats the planet, or is reflected back into space. A surface's absorption depends on how well it does the first, its albedo on how well it does the second. Some examples of surfaces with a high absorption rate are asphalt, concrete, and other dark, dry materials, which causes a heat island effect in large cities made primarily of those surfaces wherein more heat than usual is absorbed and the areas are especially hot compared to greener places nearby.

When the sun heats the earth, however, it does so unevenly, causing pockets of warm and cool air. Because warm air rises and cool air sinks, this creates uneven pressure within the atmosphere. Wind is the horizontal travel of air from high pressure areas into low pressure areas, as the atmosphere attempts to even out its own pressure. 

The earth's temperature is also affected by greenhouse gases. Though the earth's atmosphere is made of about 78% Nitrogen and 21% Oxygen, the last 1% contains gases like water vapor, carbon dioxide, methane, and more. These gases trap reemitted solar radiation into the atmosphere and prevent it from returning to space, warming the earth. Levels of some of these gases within the atmosphere has been on the rise in recent years, caused mostly by the burning of fossil fuels in human society. 

Another important factor in atmospheric behavior is the prevalence of aerosols in the atmosphere. Aerosols are small solid or liquid particles suspended in a gas, and they can block solar radiation from either entering or leaving earth's atmosphere. They are caused by many processes and events, both human and natural, and can be important or extremely damaging. Some examples of the less pleasant, polluting ones would be sulfur, nitrogen oxides, and hydrocarbons. Clouds are also aerosols.

There are three main groups of clouds: Cirro, or high altitude, Alto, or middle altitude, and nimbus, low altitude clouds carrying precipitation. These main types are further divided into cumulus, or puffy, stratus, or layered, and cirrus, or wispy clouds.

Humidity is a related concept to aerosols, referring to the amount of water molecules in the air. Air can hold different amounts of water molecules at different temperatures, however, so humidity is usually measured as a percentage of the air's water content versus the air's possible water content, with 100% being completely saturated.

Yet another thing which affects earth's climate is the gravity which creates our atmosphere by pushing air molecules toward the earth, effectively pressurizing the atmosphere. This pressure is defined as the force air exerts over an area. Air density, a related concept, deals with the amount of air molecules in a given space.This density decreases rapidly as one travels higher into the atmosphere. Air temperature decreases similarly, with the rate of decrease being called the lapse rate. Earth's atmosphere is divided into several sections based on trends in temperature for each layer. These are, in order from the bottom up, the troposphere, the stratosphere, the mesosphere, the thermosphere, and the exosphere.

Tuesday, October 16, 2012

Aerosols

     Aerosols are solid or liquid particles suspended in a gas, usually air. There are many types of aerosols, lots of which are man-made and likely what the average person thinks of when hearing the term--hairspray, air freshener, and the like. But the vast majority of aerosols are natural, ranging from the water found in clouds to dust found in dry regions of the world to sea salt from ocean spray. These are part of a planet-wide system of weather patterns which have always existed and which significantly shape the climate of every part of the earth. Many others are natural in origin, but caused by human behaviors--huge amounts of sulfate from burning fossil fuels and black carbon and organic carbon from "biomass burning" (clearing land or getting rid of farm waste).

     The primary ways these particles affect the climate is by changing the levels of solar radiation which reach the earth, either by reflecting radiation back into space or by preventing it from leaving the atmosphere once it enters. These changes can have the net effect of cooling the earth and of heating it, respectively. This makes the process of predicting climate change difficult, because while some atmospheric variables, like greenhouse gases, are well-understood and fairly consistent, the effects of the changing levels of man-made aerosols are highly varied and difficult to predict.

     This means that the long-term effect of aerosols on earth's climate is difficult to pinpoint. There are, however, other ways that they affect daily life. A change in the level of aerosols in a given area can affect visibility, as in city smog or the recently noted haze over places like the Grand Canyon. Certain man-made aerosols can be damaging when breathed in. And some of the "propellants", or base gases, once used in canned aerosol sprays contributed significantly to the thinning of the ozone layer. These propellants, called fluorocarbons, have been almost universally banned, but their effects are still being felt today.

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sources:
http://www-das.uwyo.edu/~geerts/cwx/notes/chap02/aerosol&climate.html
http://www.eoearth.org/article/Aerosols#gen4
http://earthobservatory.nasa.gov/Features/Aerosols/
http://en.wikipedia.org/wiki/Particulates
http://en.wikipedia.org/wiki/Aerosol

Wednesday, October 10, 2012

Group Work

Three things that worked in my group:
  • Everyone got along well.
  • Everyone did some work--my group members almost without exception knew what was going on and were willing to do something if it was asked of them.
  • Our presentation was the best in the business.

And three things that didn't:
  • Our time management wasn't great. We had a few days where no one did anything and one or two where we worked really hard to get it finished in time, and we had to finish up our powerpoint during presentation week.
  • I was kind of bossy/controlling. Old habits die hard, and I'm kind of a perfectionist, but I think I should have respected others' choices and work more and done less "management".
  • We didn't always allocate the work very well--some people did much more, others less. 

Tuesday, October 9, 2012

Surface Ozone

Ozone is a chemical made up of three oxygen atoms. It is most often found in the upper atmosphere, where it is created naturally when energy from the sun breaks oxygen molecules (O2) in half and binds each atom to another O2 molecule. This form of ozone is good for the earth; it protects us from harmful UVB rays, which can damage crops and cause skin cancer.

Another form of ozone, however, is less benign. Called surface ozone, it is created in the lower atmosphere by chemicals like volatile organic compounds and Nitrogen oxides (VOCs come from various man-made chemical products like cleaners and paint, while NOx are created by combustion, as in car engines) and is corrosive, damaging plants, animals, and people. It can cause permanent lung damage in people who breathe it repeatedly. And what's more, it's pervasive, because the chemicals which create it come from the burning of fossil fuels, something that western society is completely dependent on and which no one can avoid doing in some aspect of their lives, whether driving, using electricity, or heating one's house.

Because of the dangers of "bad" ozone and its ubiquity, it's extremely important that we study it to figure out how to reduce it or protect against its effects. The role it plays in air pollution is significant and unavoidable, so we must learn as much as we can.

Monday, September 24, 2012

Procedure - measuring HHS trees

We began our research of trees in the Huntington High forest by marking off a rectangle of 10 by 10 meters using twine and wood stakes. Within this rectangle, or transect, we used paint to number all trees large enough to hypothetically be used for lumber.

Using a Clinometer app on students' smartphones, we found the angle to the bottom and to the crotch of the tree 20 meters from the base in order to find the height of the tree. We also used a tape measure to find the circumference of each tree. With these numbers we calculated the size in cubic feet and board feet of the usable part of the tree.

We used a dichotomous key of North American tree species to figure out the types of trees being measured and found the value per board foot of those species, which we then calculated to get an estimated worth of each tree.

Afterward, we used ArcGIS to find the approximate area of the Huntington High forest and looked at tree value data from other classes. Using 4 transects from 4 class mods gave us an improved sample size and we used those numbers and the area of the forest to calculate the estimated (and most likely incorrect, due to measuring inaccuracies) value of the HHS forest.

Monday, August 27, 2012

Scientific Method

The scientific method is a standard logical approach to problems, and therefore it's commonly used even for decisions not made based on empirical evidence. For example, when I was making the decision last year to graduate early, I used the scientific method.

I identified the problem that I wasn't happy in school and that my classes were mostly unchallenging. Because of this, I decided to research solutions and discovered that I'd taken enough class requirements to graduate in one more year instead of two, with a little work. After some thought, I predicted that this would solve my problem by making my course load more difficult or by at least making the time spent in class shorter.

In this particular decision, I'm hovering around the next two steps--the school year has only just begun, so I suppose I'm technically experimenting with early graduation. But even so I can begin to analyze the situation and conclude that so far I'm finding a few of my classes more challenging, a few of them less so, and that I still have enough trouble with certain aspects of high school to want to leave a year early at all costs.

And I'm communicating my results right now, via this blog post.

Wednesday, August 15, 2012

Hey look. A post.

I'm Katie. I like books and the internet. I'm taking too many classes this year. One time I met my best friend from South Dakota in real life and it was awesome.

John Green is an author with a social anxiety disorder. I was in the audience when this happened.
This is a picture of John Green stage diving.