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Figure 1: Effects
of increasing CO2 on ocean carbonate level
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One of the most predictable and
measurable consequence of global climate change is ocean acidification,
which is projected to have strong negative impacts on organisms that build
their skeletons from the various polymorphs of calcium carbonate, including the
small sea-snails called Pteropods. This acidification is due, in large part, to
anthropogenic (caused by human activity) CO2 emissions into the atmosphere, a
significant portion of which is absorbed by our oceans. It has been reported
that the ocean absorb as much as 25% of CO2 that is released
into the atmosphere (EPOCA report). This is a large amount, given
the current rate at which this particular greenhouse gas is being
emitted. At this current rate, it is estimated that by the end of this century,
oceanic pH will drop by 0.4 (http://www2.cnrs.fr/en/1544.htm).
The role of the ocean waters as a carbon sink to ameliorate the rate of global
warming will also negatively affect the composition of our marine ecosystem
(through ocean acidification) if current rates of emission of CO2 is maintained at business-as-usual (http://www.sciencedaily.com)
.
At this point, you may be asking yourself,
"what's the big deal if the ocean becomes more acidic?".Well, part of
the answer to that question is precisely what this blog intend to address.
As outlined in the schematic above, increased CO
2 mixed with sea water will give rise to
carbonic acid and therefore make the ocean slightly more acidic than may be
conducive for certain calcifying marine organisms such as
Limacina helicina . The decreased carbonate
concentration (as a result of increased CO
2-Le Chatelier’s
principle) will lower the saturation state (Omega) of a major component of
these organisms' shell (Aragonite) and thereby decrease the calcification rate/
or accelerate the dissolution rate of their shell because carbonate is a major
reactant in this species' shell composition (
http://www.terrain.org).
Furthermore, the negative effect of ocean acidification has far reaching
consequences than just jeopardizing the fitness of calcifying organism (after all,
who really is excited about "having L.helcina for dinner?).This
zooplanktonic species is an important food source for some of the fishes that
society depends on for nutritional and economic reasons. Pink Salmon, for
example.
Not exactly sure what your figure is showing. Maybe add arrows indicating the direction of the cycle or add a legend to the figure.
ReplyDeleteThanks Abby for the feedback. I'll incorporate your suggestions in the final draft. Actually, the figure wasn't meant to be a cycle. I was simply trying to show how increased CO2 would lead to low seawater PH which would have a deleterious effect on zooplankton population. Since zooplankton is a primary food source for Salmon, we will see a decrease in Salmon population as a result.
ReplyDeleteDoes that makes sense ?
I agree with Abby, that the figure needs to be clarified a little, but other than that you seem to have provided a clear explanation of what the issue is here
ReplyDeleteThanks Will:) I'll work on it.
ReplyDeleteI am not sure if this is just my computer, but there are random new lines in the middle of sentences and it makes it kind of hard to read. Also the figure is a little confusing, but you are already addressing that. At the end of your introduction, you say you will investigate how climate change will effect zooplankton. This is slightly confusing since your blog is about salmon. Overall though, other than a few grammatical errors, I thought this introduction was a well written description of what is going on and what you will be discussing in the rest of your blog.
ReplyDeleteI agree with Abby. I'm not sure what your original figure is showing and the layout of the sentences are a little hard to read. Moreover, I think more details on the cues for 'indirect effect on salmon population' tabs would be nice. Some pictures don't go with the information on the tabs. But overall, good job !
ReplyDelete