To fleece or not to fleece!

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I found this discussion on the pros and cons of fleece in the September/October 2012 issue of Sierra.   It’s a terrific example of the trade-offs and choices we need to make daily.  Remembering that the results of all of our actions flow outward like water rings in a pond, Greenmomsters have to decide what works for them and then make decisions based on the available scientific information.  The process can be frustrating at times, but it’s our responsibility to think about our impact on the environment.  There won’t always be clear-cut answers, but if you’re giving these issues some thought, you’re part of the solution!  To fleece or not to fleece, that’s the question for you to answer!

The following article and image are from Sierra (September/October 2012, p. 20, article by Dashka Slater):

ON THE ONE HAND . . .

Ah, fleece--it's insulating, it's quick drying, and it can be made of recycled materials, plus it gives even prickly environmentalists a soft, pettable exterior. Vegans like it because it doesn't come from animals, backpackers like it because it can weigh less than wool, and tree huggers like it because it gives old pop bottles something to do. Patagonia, which began making polyester fleece garments from recycled plastic soda bottles in 1993, estimates that in its first 13 years of turning garbage into garments, it diverted 86 million soda bottles from landfills.

ON THE OTHER . . .

Every time you wash that cuddly fleece jacket, tiny plastic particles trickle down the drain and into the ocean. A study published in the journal Environmental Science and Technology found that a single polyester garment can shed more than 1,900 fibers on its trip through the washing machine. Those fibers sail through sewage treatment plants and settle along coastlines. When researchers sifted through sand collected from 18 beaches on six continents, they found acrylic and polyester fibers in every sample. The fibers get eaten by mollusks and then move up the food chain with potentially toxic results.

The Other CO2 Problem

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Last night, I attended a screening of the National Resources Defense Council’s  (NRDC) new film, “Acid Test:  The Global Challenge of Ocean Acidification.”  This 20 minute film is definitely worth the time to watch, and the NRDC has generously allowed free distribution.  I hope you’ll take a little time to watch it.

Usually we’re focusing on CO₂ as the man-made cause of climate change – we burn various types of fossil fuel (releasing a molecule called CO₂ or carbon dioxide) which leads to changes in our atmosphere and an average increase in long-term global temperatures.  But, as is shown in this film, there’s another impact of CO₂ emissions.  When CO₂ accumulates in the atmosphere, it often enters the ocean as well.  In the ocean, CO₂ reacts with water to form carbonic acid.  The NRDC states, “Since the start of the Industrial Revolution about 150 years ago, approximately one-quarter  to one-third of all CO₂ from fossil fuels – or about 500 billion tons – has been absorbed by the seas, increasing the average acidity by 30 percent.”

Now, you may have the same reaction that I did – sure, 500 billion tons is a lot, but the oceans are pretty darn big too.  I mean, they can be as deep as 5,000 meters.  Fortunately, the local chapter of the Sierra Club, which sponsored the film screening, invited a local oceans expert from George Mason University to answer some questions.  He explained that the portion of the ocean that we most commonly encounter is the top 200 meters.  That’s where we find most of the sea life on which we depend.  That’s where fluctuations in currents impact our climate and weather.  So 500 billion tons into the top 200 meters can have a very substantial effect on the health of our oceans. 

Ocean acidification affects the many species of animals that build exoskeletons, or external shells or skeletons.  These animals need carbonate (another molecule) from which they build these exoskeletons.  The availability of carbonate is negatively affected by an increase in ocean acidity (or a drop in pH).  If ocean acidity gets high enough, the environment can even become corrosive to the shells of these organisms.  The worry is that many of these species could become depleted or even extinct.

But what if you’re not really interested in ocean ecology?  Who really gives a flying flit if a few little invertebrates can’t make shells?  Well, those little invertebrates are the basis of the ocean food chain.  Little animals get eaten by bigger animals, which get eaten by bigger animals.  Humans are part of this food chain.  The reason to care, if you’re not concerned about species extinction and nature in general, is that your food source could be severely impacted.  For great information on worldwide fisheries, check out UN Food and Agriculture, Fisheries and Aquaculture Department.

The NRDC makes some suggestions for greenmomsters who want to do their part in turning around this damage to our oceans:

• encourage your local, state, and federal government to adopt an energy policy that invests in efficiency and encourages renewable sources based on wind and sun;
• encourage the federal government to establish a strong national policy to protect, maintain, and restore the health of marine ecosystems, end overfishing, and create marine protected areas;
• do your part to reduce use of fossil fuels through conservation at home and on the road.

Any comments on the film?

So you slept through science class, part 2 – molecules, energy, and zebra dung!

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In the last post about the basics of science, we talked about DNA.  I mentioned that DNA is a molecule, and I outlined its structure and the mutations that can occur in this molecule.  Let’s back up a little this week – what exactly is a molecule (for those who always wanted to know, but were afraid to ask)? 

Science talks about something called “matter.”  “Matter” is anything that has mass and occupies space.  Thus, just about everything you can see and feel is made of “matter.”  If we continue to drill down, we find out that matter is made of building blocks called atoms.  Just think of atoms as the Legos in this picture, and the castle (matter) is made of atoms.  Science textbooks describe atoms as the smallest particle of an element that still retains all of the properties of that element.  But what is an “element”? We’ll get back to that in a minute.

When we look at atoms, we see many particles that make up atoms.  These particles are called “sub-atomic particles,” and we usually refer to three distinct “sub-atomic particles”  -- protons, neutrons, and electrons.  Protons and neutrons hang out sort of in the center of the atom (the nucleus), while the electrons fly around the nucleus.  The particles are extremely small, with electrons being the smallest.  To give some perspective to the relative size of these sub-atomic particles, (this is really cool…) think of the atom as being the size of FedEx Field or any other large stadium.  The nucleus, with its protons and neutrons would be roughly the size of a fly sitting on the 50 yard line.  The electrons would be about the size of a few gnats flying around the rest of the stadium!

So now we know that protons, neutrons, and electrons make atoms which combine to make matter.  But what about elements and molecules?

Each individual atom has a set number of protons in its nucleus (the center of the atoms).  An element is a substance consisting of atoms that all have the same number of protons in their nuclei.  So for the castle above, if it were made from one element, all the Legos would be the same.  Oxygen is an element – every oxygen atom has 8 protons in its nucleus.  If the atom had 7 or 9 protons, it wouldn’t be an oxygen atom; it would be the atom of a different element (the element nitrogen for 7 protons in each atom; the element fluorine for 9 protons in each atom).  Carbon is an element – every carbon atom has 6 protons in its nucleus.
 
A molecule is simply the smallest particle of a substance -- any substance like water, DNA, or salt (compare that to an atom, which, as we said, is the smallest particle of an element).  At this point (the molecular level) , we’re mixing atoms of various elements to make new substances.  We’re no longer just dealing with elements, where every atom is the same.  Now we’re mixing various types of atoms to make things like water, DNA, or salt.  Molecules can be combinations of different atoms, or several of the same atom.
So, for organization of matter, we’ve got sub-atomic particles (protons, neutrons, electrons) –>atoms –> molecules.

At this point, my students are raising their hands and asking, “will this be on the test?”  I need to answer the all-important question – Who gives a flying flit about molecules and matter?  What does this have to do with environmental awareness?

Here’s why we care: 

photo by William Widmer

New reports often talk about chemical contamination in our food and water.  We read about air pollution or second-hand smoke that affects our lungs.  We hear about possible new renewable energy sources.  All of these topics are talking about molecules – scientists are working at a molecular level to answer questions and solve problems.  Here’s a great example – I was just reading an article by Guy Gugliotta in the New York Times about a possible new energy source – cellulose, a large molecule found in plant cells.  Researchers are looking for a microbe in the dung of various zoo vegetarians (giraffe, zebra, etc.) that provide a simple way of turning cellulose into a renewable energy source.  Research at a molecular level could provide a new, renewable energy source! 
So there you have it -- molecules in a nutshell.  And, yes, nutshells are made of molecules.