(photos from http://ina.tmsoc.org<)

Coccolithophores are single-celled, marine algae With shells made up of CaCO₃ Most of them live in the ocean’s upper photic zone They are the base of the food chain, eaten by zooplankton.

Sunlight and nutrients they do share at the surface When all of them are there, nutrients become scarce Though in the lower photic layer, some prefer to live there Where nutrients are abundant and light is rare.

These are coccolithophores, the organism is inside

Surrounded by calcite scales that are preserved when they die

They are called coccospheres, when preserved as a whole

Or termed as coccoliths in their disaggregated form.

They have organic base plate scales with complex ornamentations

That collect CaCO₃, the process is calcification

And then they form all these intricate structures

Remarkable pieces of Earth’s architecture. 

They are minute, approximately 2 to 30 microns in size

You cannot see them with your two naked eyes

Light or scanning electron microscopes is what we use

We identify and count them to find some clues.

So you can just imagine how much they can cover

Oceans with areas of thousands of kilometers

If they gather altogether, they can form a bloom

There can be thousands of them or even millions.

In the global carbon cycle they play a significant part

They have combined effects on biological and carbonate pumps

Huge amount of CO₂ is sequestered via photosynthesis

And by calcification, back to the atmosphere, the CO₂ is released.

Together with other guys like foraminifera and pteropods

For the ocean’s vertical gradient alkalinity, they are responsible

Coccolithophores also form organic compounds called alkenones

Depending on the sea surface temperature, they vary in configuration.

And when these organisms die, their remains fall

Drift down by the currents to the bottom, down the floor

One of their enemies though is the calcite compensation depth

Where they will most likely get dissolved and experience double death.

But for those that have managed to reach the seafloor

They build up in the sediments, stay for years and more

Over the geologic time, as seas advance and retreat

Tectonic plates moving around can expose those beneath.

Though not all have to wait that long thru the geologic time

To be exposed to the surface and see the day light

Yes, there are those like the famous white cliffs of Dover

But there are also those sediment cores collected with a corer.

Some theories about them may still be debatable

But we cannot negate the fact that they have important role

If we hope to understand our current and future climate

It is imperative that we understand the Earth’s past state.

Our oceans, they present a unique opportunity

For scientists like us to discover and study

For thousands of years, marine sediments can remain untouched

They provide excellent records for reconstruction of the past.

Now I have this chance to sail with the Joides Resolution

Find some of them in the cores that we will get in this expedition

Under the microscope, I will always gaze at them in awe

For I can never fathom, the depths of what I am to know.