PDS APES 8th Period 2009-10

Since our scribe never got this topic posted, here is a link to a good summary of the topic from the other class:

http://pdsblogs.org/pdsapes510/2010/04/22/acid-rain/

Don’t forget indirect effects of acidic soils…just as important as direct damage from acidic precipitation!

*This is a guest post by EmilyO in the other class.  Not sure everyone was there due to APs and not sure those that were there were very focused, so maybe this will be of use…

On Wednesday we reviewed some of the qualities of soil. To do this, we looked at a soil profile, and we also made our own edible version.

A soil profile is a view of the different layers of soil from the side, so it’s easy to separate each one. These layers are also called horizons, and there are four main ones that our text mentions- O, A, B, and C. Page 49 of our text has a good description as well. http://soils.usda.gov/education/resources/lessons/profile/profile.jpg

A soil profile that contains the basic horizons.

Each of the horizons have distinct qualities that separate them from the others:

• O- This is made up of the seasoned, dead organic matter known as “leaf litter.” It contains detritivores, and other small insects. The material we collected during the Davidson field trip was the O layer.
• A- This is the topsoil. Combined with the O and E, which isn’t necessary to know, layers it makes up the zone of leaching. Humus is also found in this horizon. Humus is the nutrient-rich soil that is dark brown in color.
• B- This is the subsoil and the zone of accumulation.
• C- This is the parent material, which is made up of weathered, larger rocks. The R horizon lies below the C and is known as bedrock, but it isn’t necessary to know this layer either.

We then went on to make our own ice cream version. First we added cookies, which were the R layer, next was the ice cream, which was the C layer. On top of that we put whipped cream as the B layer and pudding represented the A layer. The O layer was a combination of nuts, chocolate chips, and other toppings. This helped us to visualize what makes up each of the horizons.

We also reviewed a soil triangle; it might be nice to make sure you know how to read one- clay is read on the horizontal, and silt and sand are read on the diagonal.

A soil triangle, notice how each one is read on different angles.

http://www.oneplan.org/Images/soilMst/SoilTriangle.gif

A review over the qualities of sand, silt, and clay:

Sand- It is the largest of the three and is very permeable, so it doesn’t retain water well. This results in lots of leaching, which causes nutrients to be lost because they are “leached” downwards through the horizons. This causes sand to have poor nutrient retention. On the other hand, it has very good water infiltration (absorption), but poor aeration.

Silt- It is the second largest and retains water and nutrients fairly well. Its aeration and ability to absorb water are fair too.

Clay- It is the smallest of the three, and retains water and nutrients well. However, it has poor water absorption and aeration.

A combination of the three soils makes the “best” type of soil, which is known as loam. Loam exhibits the best qualities of all three particles, which is why it’s so good. That was about it, so I hope this helps anyone who needed a review of soil!

Alright, I know I post a lot of stuff on here, but I just spend some time on stumbleupon.com and I stumble upon lots of relevant stuff.

Take this for instance. It is a really helpful model showing how all of our trash ended up in the middle of the Pacific ocean in the gyre. I never quite understood how it all condensed until this model.

Dr. Crumley sent me this one….

Can you believe this?

Source: http://andrewsullivan.theatlantic.com/.a/6a00d83451c45669e20120a95679e3970b-popup

Hey guys, I just stumbled upon this cool website about our use of the Great Lakes:

Water life

It’s a bit dramatic and biased, but if you are looking at it for nothing else, it has cool music and graphics.

Today we talked about hydrogen and how it can be used to power vehicles. Of the forty-four free response questions on previous A.P. exams, none have addressed hydrogen power, so Mr. Willard said this would be “good knowledge to have in our pockets.”

First we reviewed what we already knew about hydrogen. Hydrogen is the most abundant element in the universe. Despite this fact, there is almost none in the troposphere, and this is because hydrogen has a very low density and so it rises. Additionally, hydrogen is very unstable, so it likes to bond with things (i.e. with oxygen, thus water).

In a hydrogen-powered car, the traditional internal combustion engine is replaced with a fuel cell. Here is a link to a video we watched in class about how a fuel cell works: How A Fuel Cell Works: Inside A Hydrogen-Powered Car (http://auto.howstuffworks.com/fuel-efficiency/alternative-fuels/dangerous-hydrogen-fuel1.htm)

As with every energy source, there are pros and cons. The pros to a hydrogen-powered car is that water is its only emission, it is a strategy for reducing fossil fuel use, and hydrogen is the most abundant element in the universe. On the flip side, the cons to a hydrogen-powered car are that we have to harvest the hydrogen or “make it” (which requires energy input), since this source of energy is new, the infrastructure for hydrogen power is not there, and that we can’t simply convert petro-gas stations to hydrogen gas stations. Perhaps we can add on to our petro-gas stations, and if we harvest the hydrogen or “make” the hydrogen by generating energy from renewable resources such as wind or solar power, technically the energy is still clean. But if we generate the energy for hydrogen from a coal-based power plant, then we’re just moving the source, but the impact is still the same.

Hydrogen can be “harvested” or “made” from electrolysis (splitting water), from biomass, and from fuel.

The U.S. Government is currently funding research on hydrogen power in the state of California. Hydrogen power is still very much in the research and development stage. Hope this helped!

Below is a picture of a typical hydrogen fuel cell:

http://images.google.com/imgres?imgurl=http://www.che.tamu.edu/groups/Wood/H2%2520movie_files/image003.gif&imgrefurl=http://www.che.tamu.edu/groups/Wood/H2%2520movie.htm&usg=__K3fNnt0v-ftXo11ZxrB83AVzpL0=&h=450&w=450&sz=26&hl=en&start=6&um=1&itbs=1&tbnid=11w-PWqxONm6CM:&tbnh=127&tbnw=127&prev=/images%3Fq%3Dhydrogen%2Bfuel%2Bcell%26um%3D1%26hl%3Den%26sa%3DN%26rlz%3D1R2GGLL_en%26tbs%3Disch:1

Plate Tectonics and the Rock Cycle

http://www.merrittcartographic.co.uk/plate_tectonics.html

The theory of plate tectonics came about in the mid twentieth century after compiling centuries of speculation andcontemporary  oceanographic studies that suggested that the earth’s surface was actually made up of moblie plates of solid rock floating on a sea of liquid hot mantle that flows at a rate of inches per year.  This mantle operates like a convection cell with hotter liquid metal rising towards the surface and denser cool rock sinking down back towards the Earth’s core.  The floating rocks, or plates, each cover immense area on the Earth’s surface and fit together like a 20ish piece puzzle across the globe.  The most interesting part of the theory of plate tectonics is the area where two plates meet, or a plate boundary.  Due to the plate boundaries unstable and mobile nature, volcanoes and earthquake activity cluster around active boundaries, which are sometimes referred to as faults.  The most notorious of these active regions surrounds the Pacific Plate, the largest tectonic plate on Earth, is dubbed the “Ring of Fire”.  This is one of the most highly active areas on the earth and contains a plethura of subduction zones and oceanic trenches that contribute to massive earthquakes and tsunamies, as well as a multitude of active and inactive volcanoes.  The subduction zones, most of which are in the pacific off the coast of asia and North America, create deep abysses and ocean trenches.  The marianas trench, the deepest point on the Earth, is the subduction zone on the Western plate boundary of the Pacific Plate.

Plate tectonic activity

The Rock Cycle

http://www.emc.maricopa.edu/faculty/farabee/BIOBK/boundaries.gif

The rock cycle is constantly in motion across the planet, and keeps recycling rock over eons through natural processes.

https://www.e-education.psu.edu/files/earth530/image/rock_cycle.gif

I haven’t done an “in the news” bit in a few weeks, but her are some hot topics you guys have brought up in class or sent to me by email. See something of interest? At this point in the year, reading the news is kinda a form of studying for the AP exam…isn’t it?

China Became Top Wind Power Market in 2009
http://planetark.org/wen/57361

U.S Approves Wind Farm Off Cape Cod
http://www.nytimes.com/2010/04/29/science/earth/29wind.html?emc=eta1

Drilling Deep Under the US to Dispose of Nuclear Waste
http://www.newscientist.com/article/mg20627544.600-drilling-deep-under-the-us-to-dispose-of-nuclear-waste.html

Ukraine Leader Says Kiev Needs More Chernobyl Funds
http://planetark.org/wen/57762

Europe Finds Cleaner Energy in Trash, U.S Lags
http://www.nytimes.com/2010/04/13/science/earth/13trash.html?pagewanted=3&ref=world

Oil Spill From Sunken Rig May Threaten Gulf Coast
http://www.npr.org/templates/story/story.php?storyId=126214809&sc=17&f=1007

Oil Leak Could Take Months to Stop
http://www.nytimes.com/2010/04/26/us/26rig.html?emc=eta1

Coast Guard Sets Oil Slick Ablaze
http://planetark.org/wen/57769

Global Floating Ice in “Constant Retreat:” Study
http://planetark.org/wen/57771

EPA Phases in Permits for Greenhouse Pollution
http://planetark.org/wen/57356

How Cap and Trade was “Trashed” (Congress debates CO2 emissions trading recently)
http://www.npr.org/templates/story/story.php?storyId=126280761&sc=17&f=1007

U.S., Canada Crack Down on Vehicle Emissions
http://planetark.org/wen/57423

Hong Kong Issues Warning as Air Pollution Sets Record
http://www.nytimes.com/2010/03/23/science/earth/23hong.html?emc=eta1

Could Cleaner Air Actually Intensify Global Warming?
http://www.npr.org/templates/story/story.php?storyId=126226938&sc=17&f=1001

Iceland Volcano: Not Yet a Global Cooling Eruption
http://planetark.org/wen/57594

Green Groups Point to Ash Cloud Silver Lining
http://planetark.org/wen/57681

Earth’s Missing Heat Could Haunt Us Later
http://planetark.org/wen/57592

Industrialized Nations’ CO2 Falls 2.2 Percent in 2008
http://planetark.org/wen/57679

Timeline: 70 Years of Environmental Change (NEAT interactive history review!!!)
http://www.nytimes.com/interactive/2010/04/22/science/earth/20100422_environment_timeline.html?emc=eta1

So, last year the APES text (published 2008) had a section on carbon offsets-first time I’ve seen it in a school textbook. There are many companies out there now marketing carbon offsets to reduce your “carbon footprint.” Terrapass is a popular one. You can offset one year’s worth of air travel (an estimated 8,000 pounds of carbon emitted) for just $50.60 as of 4/30/2010. Your money goes to support wind farms and methane capture projects-that’s how the carbon is “offset.”  Some companies will even plant trees to offset carbon produced by your lifestyle.

So, does this approach mitigate (lesson) global climate change or encourage “cheating?” Watch this clever parody of carbon offsetting by a couple of Brits:

*If you want to learn more, visit www.cheatneutral.com

So, what do you think?

*Try www.carbonfootprint.com to for a carbon calculator if you want to assess how much carbon dioxide results from your lifestyle.

Mr. Willard said that we should already know about the background about ozone, but here’s a quick glance at what he was talking about:

• Ozone is a “global sunscreen” for the Earth. It blocks  and absorbs 95% of UV radiation!
• The ozone layer is 12 miles or 20 kilometers thick.
• The ozone layer exists in the stratosphere, and is considered “good ozone.”

Good Ozone vs. Bad Ozone:

Bad Ozone (Tropospheric Problem): Ozone (O3) can exist in the troposphere at ground level, but is “bad ozone,” because it can cause lung disease.

Good Ozone (Stratospheric Problem…if there’s a “hole”): The thing about “good ozone” is that it does absorb and block UV radiation. The thinning of the ozone layer, or what we now call the “ozone hole” is really a  dip in the thickness of the ozone layer. This thinning is caused by chloroflourcarbons (CFCs). These CFCs are “dream chemicals” that are odorless, nonflammable, and nontoxic and are used in aerosol cans, cleaning agents and coolants. When the UV radiation hits the CFCs, the following reaction breaks down the ozone into toxic chlorine (Cl) and diatomic oxygen. This cycle can be repeated thousands of times and this is the reason the ozone layer is being destroyed so quickly.

Cl + O3–>ClO + O2

ClO + O–> Cl + O2

Unfortunately, the thinning of the ozone layer has caused more UV radiation to penetrate the ozone layer. (The “hole” is largest during the Antarctic spring [September-October.]) This  UV radiation comes in two forms: UV A and UV B which both can cause cataracts and skin cancer in humans (UV A rays have wavelengths deep enough to cause squamous cell carcinoma in humans, and UV B rays have wavelengths shallow enough to cause melanoma),  damage DNA in animals and plants, reduce phytoplankton, and reduce crop yields.

Squamous Cell Carcinoma

Melanoma

In the 1980′s, scientists began observing the ozone layer, and in response to the “hole” observed near Antarctica and Europe, the international community came together a created the Montreal Protocol. This was designed to protect the ozone layer by reducing the CFC output by 1/3 by 2000 and bring back ozone levels to 1950 levels by 2100.

Ozone Levels 1980-1991