Packing for a Journey into the Twilight Zone

Submitted for your consideration: A team of researchers from

more than 20 institutions, boarding two research vessels, heading into the ocean’s

twilight zone.

The twilight zone is a dimly lit region between 650 and 3300

feet below the surface, where we’re unfolding the mystery of how tiny ocean

organisms affect our planet’s climate.

These tiny organisms – called phytoplankton – are plant-like

and mostly single-celled. They live in water, taking in carbon dioxide and

releasing oxygen.

Two boats, more than 100 researchers from more than 20

partner institutions, and a whole fleet of robotic explorers make up the EXport

Processes in the Ocean from RemoTe Sensing (EXPORTS) team. We’re learning more

about what happens to carbon dioxide after phytoplankton digest it.

The Equipment to Find

Phytoplankton

Phytoplankton have predators in the ocean called

zooplankton. They absorb the phytoplankton’s carbon, carrying it up the food

chain. The EXPORTS mission will focus partly on how that happens in the ocean’s

twilight zone, where some zooplankton live.  When phytoplankton die, sometimes their bodies

sink through the same area. All of this carries carbon dioxide into the ocean’s

depths and out of Earth’s atmosphere.

Counting Life

Studying the diversity of these organisms is important to

better understand what’s happening to the phytoplankton as they die.

Researchers from the Virginia Institute of Marine Science are using a very fine

mesh net to sample water at various depths throughout the ocean to count

various plankton populations.

Researchers from the University of Rhode Island are bringing

the tools to sequence the DNA of phytoplankton and zooplankton to help count

these organism populations, getting a closer look at what lives below the

ocean’s surface.

Science at 500 Feet

Taking measurements at various depths is important, because

phytoplankton, like plants, use sunlight to digest carbon dioxide. That means that

phytoplankton at different levels in the ocean absorb and digest carbon

differently. We’re bringing a Wirewalker, an instrument that glides up and down

along a vertical wire to take in water samples all along its 500-foot long

tether.

This journey to the twilight zone will take about thirty

days, but we’ll be sending back dispatches from the ships. Follow along as we

dive into ocean diversity on our Earth Expeditions blog: https://blogs.nasa.gov/earthexpeditions.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

https://xissufotoday.space/2018/08/packing-for-a-journey-into-the-twilight-zone/