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cats
Fufi, Zeus, and Sammy all got adopted since
last week. A crew from Channel 7 was at the shelter today
interviewing Stacy about feral cats and strays. They filmed
some of the cats, including Jaguar, Quincy, and Susie.
Filming while we were cleaning slowed things down quite a
bit and I had a distinctly workaholic moment when I realized
that I resented them for keeping me from getting work done.
I ended up leaving early because I'd forgotten to take
Motrin for the mysterious knee thing and after standing
still washing dishes after being up and down cleaning cages
the stupid knee hurt a lot. There must be more to say about
the whole cat thing but as I noticed yesterday, my writing
is becoming pedestrian.
spell checker
I installed Claris Home Page 2.0 yesterday
(it came included with ClarisWorks). Not only does it fix
the annoying bugs in 1.0 but it also has a spell checker. So
I ran all of March, April and May entries through it just to
clean up my typos. Much to my surprise, the spell checker
did not recognize: dyke, fuchsia, zooplankton, and a couple
of other words I can't remember right now. I can forgive it
zooplankton on the grounds that it's a specialized term, but
dyke and fuchsia? Give me a break!
the ozone hole
I turned in my paper on the effect of the
Antarctic ozone hole on icefish larvae and took the final
exam tonight so Oceanography is over for the year except for
the field trip to take bottom samples and water samples in
Dorchester Bay on Friday. Boy is that a long sentence and
awkward!
What you may ask is the ozone hole? And what does it mean
to you? I know you all want to know.
The Ozone Layer.
Ozone occurs naturally in the earth's
stratosphere. This layer of ozone is what allowed the oceans
to form and life to evolve on earth. Before the atmospheric
ozone layer, life was possible only in the ocean depths
where the seawater absorbed the sun's ultraviolet radiation
. Starting about 600 million years ago, oxygen began to
build up in the atmosphere as a result of photosynthesis.
Ozone is chemically formed from oxygen. As oxygen levels
increased, ozone levels increased until there was enough
ozone in the atmosphere to absorb effectively the
ultraviolet (UV) radiation coming from the sun. Only with
this protection, could living organisms emerge from the
oceans to live on land.
Ozone and UV-B Radiation.
The key role of the ozone layer is to filter
out radiation in the middle of the UV spectrum, which
includes UV-B. UV-B is the most biologically damaging part
of the UV spectrum. These midrange wavelengths are the ones
responsible for health problems in humans, plants,
livestock, marine life, etc. DNA absorbs UV-B light and the
absorbed energy can break bonds in the DNA.
The Ozone Hole.
The ozone layer has been thinning over the
past twenty years. Satellite measurements of ozone started
in the early 70's, but the first comprehensive worldwide
measurements started in 1978. (Ground based measurements of
Ozone were first started in 1956.) Ozone depletion is most
dramatic over Antarctica. Each year since 1979, the ozone
layer thins dramatically over Antarctica. In the 1980's
scientists had predicted about a 7% decline over a 60 year
period. Ozone levels have fallen gradually in the more
temperate latitudes as predicted. However, the satellite
data showed a greater than 50% depletion of the ozone layer
over Antarctica that recurs each austral spring for about 10
to 12 weeks. This 50% decline in ozone concentrations over
Antarctica is referred to as the Antarctic ozone hole.
There, that wasn't so bad, was it?
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