I’m going to warn you – the next few posts are likely
to surround the topic of climate change, as a partial continuation of the previous one, but also because a pretty big topic has recently been brought to
my attention, and I wanted to explore it a bit further. So, Part One of this “two-part
series” will focus on how the oceans are being impacted by climate change.
***
Each year between 1970 and 2010, the temperature of
the shallowest waters of the ocean increased by 0.1°C. This may not seem like a
lot, until you look at that accumulatively. There’s 40 years recorded there, at
0.1°C per year, which is 4°C*. Again, 4°C likely doesn’t seem all that
significant, but the reality is that this actually has quite negative
implications for the aquatic life found within these waters, as well as the fact
that overall wellbeing of the oceans themselves are highly compromised. How exactly?
Well, in a number of ways – with some being more obvious than others, of
course.
To start, there’s this whole thing around sea level
rise. With mass ice melt happening around the world – particularly the
frightening acceleration of the Greenland Ice Sheet finding its way into the
ocean in liquid form – water levels are beginning to rise. This mostly impacts
those living in coastal regions, such as my home province of Nova Scotia. But,
as a bonus to these rising sea levels,
the instances of drowning wetlands are also becoming a common occurrence. This
means that coastal areas – wetlands – aren’t able to keep up with the rising
water levels of the ocean, creating these neighbouring coastal areas to be submerged
under water. Again, this is important because wetlands house a number of
important species and ecosystems that are part of the already delicate balance
of the natural world. So, seeing these two related impacts of climate change, happening
before our eyes, is kind of important and alarming!
Okay, so you may be asking what’s the problem with a
little extra water floating around? I’ll tell you what – it has a little
something to do with a thing called the jet stream and ocean currents!
The currents that occur in the oceans are the result
of a mixture of the earth’s latitudes** and varying water temperatures. What
this means is that the warm air near the equator sucks in cooler air, which
generates what is known as circulation cells. This is why it’s colder in the
poles than at the equator. But, these circulation cells also bring about wind.
Wind is important for the movement and temperature control
of the water. But, the warming of the oceans directly impacts the capacity of
these wind patterns, which leads to the warming of the oceans’ waters, and as a
result melts the ice that currently forms glaciers. And with this melt comes,
the dilution of the ocean water, which leads to an inability for that cooler
water to be pushed below, thus disabling the regulation process of ocean temperatures.
This also leads to the creation of more extreme weather patterns***.
This destabilization of wind patterns also hinders the
ocean currents from continuing another important function – providing nutrients
to aquatic life particularly near the equator. If this provision of nutrients were
to cease, well, say bye-bye to the ocean food chain, the many ecosystems within
these vast areas of the planet, as well as an even more difficult process for
the oceans to absorb carbon (this will be discussed in a second – stay with
me!), leading to further – you guessed it – global warming!
In addition to these warming ocean temperatures is the
occurrence of fish migration (which will somewhat be the basis of Part Two). Basically,
as a result of the warming waters, fish species are beginning to migrate
outside of their regular territories. In recent studies, there has been indisputable
evidence to show that many fish species have been drawn towards the poles as a
result of warmer water temperatures.
And finally, we should probably have a discussion
about ocean acidification. One of the incredible functions of the oceans is its
ability to absorb carbon dioxide – especially the nasty amounts we, human-folk,
produce. It is believed the ocean can absorb around 30% of what we produce,
although this has been challenged significantly in recent history, given the
amounts created by humans each year. What does this mean? Well, the pH level of
the ocean is beginning to drop, which has increased the acidity of the water.
Part of this acidification involves coral bleaching. The
term coral bleaching refers to the
physical colour transformation that takes place when the nutrients, and
essentially, life of, coral ceases. We all associate coral, and more broadly
coral reefs as being full of a variety of colours and movement. But, when coral
dies, it turns a sedentary, white colour, devoid of life. The rise in water
temperature has a major part in this transformation, as does pollution. And
while this may not seem like a big deal, coral is an essential part of ocean
wellbeing because it’s home to a lot of food sources not only for us humans,
but a number forms of aquatic life.
Furthermore, this acidification leads to another complication
for ocean wellbeing - the reduction of sulfur moving from the ocean into the
atmosphere. The result of this inhibited process, is that it essentially
prevents the reflection of solar radiation between earth and the atmosphere
(and beyond), which is one of the ways this warming process we hear so much
about takes place.
But what does this all mean for those of us living outside of the oceans? Well, a lot,
actually. When you think of just how significant the ocean is in terms of the make-up
of the planet, we know it makes up approximately 70% of the earth’s surface.
These oceans aren’t just there for us to access fish, or to enjoy a casual day
out on the water – they actually directly impact climate and weather patterns,
as was noted above. The scary bit about these impacts to climate and weather in
the oceans, is that they also directly influence these same patterns in-land. Remember
those droughts that seemed to affect most of the world this past summer? Don’t
think this isn’t related to what’s happening in the oceans. The intensity of
recent hurricanes, cyclones, and the lack of heavily dependent upon monsoons in
several areas (such as parts of sub-Saharan Africa) are also a part of all this.
They can impact everything from how food is produced (or not), to loss of
coastal land, and even damage to homes and other livelihood-related impacts.
So, to say what happens in the oceans stay in the oceans is on massive
misunderstanding!
 |
| Lawrencetown Beach, Nova Scotia - aka one of my favourite places on earth |
The realities of our changing climate can be found in
all corners of the earth, if only we open our eyes wide enough to full accept
what is happening around us. As someone who grew up near the Atlantic Ocean,
maintain it as a multi-functioning ecosystem is something I need to pay more
attention to. I also really hope to return home one day (and hopefully
throughout the years to show it off too many friends made along the way) to eat
all the fish in said ocean, so please, for my own selfish sake, keep my ocean
happy and healthy!
-the Orange Canadian
*That 4°C, by the way, is equivalent to 7.2°F.
**Meaning, where in the world, latitudinally, these
waters are located, as in the difference between the equator and the poles, and
anywhere in between!
***Hellllloooooo Environmental History, circa 2011!
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