The ocean is vast,
covering over 70 percent of the Earth's surface,
containing 97 percent of the planet's water,
and holding almost 50 times more carbon than the atmosphere.
For something so large to change would seemingly be impossible.
But the ocean is changing,
and NOAA's Pacific Marine Environmental Laboratory, or PMEL,
has been measuring these changes, including changes in ocean carbon,
for over 30 years.
To see long-term changes in the carbon cycle,
the cycle by which carbon moves between the land, air, and the sea,
NOAA uses a network of carbon sensors in the air,
such as on top of Seattle's Space Needle,
and at the ocean surface, deployed on more than 30 buoys
found in open ocean, coastal, and coral reef ecosystems.
PMEL scientists also use sample bottles
to collect seawater from various depths in the ocean,
and the samples are analyzed to paint a picture of how carbon dioxide
transports away from the ocean surface and into the ocean interior.
The resulting data is clear.
Carbon dioxide levels in the atmosphere have skyrocketed since the 1960s--
the result of increased fossil fuel burning
coupled with the depletion of natural habitats.
As more and more carbon dioxide enters the atmosphere,
it, in turn, passes into the ocean.
Data from PMEL's ocean sensors show
that almost a third of the carbon dioxide we release into the atmosphere
is absorbed by the sea--
approximately 22 million tons every day.
Once in the ocean, carbon dioxide reacts with water molecules
to form carbonic acid, in a process called ocean acidification.
Over the past two centuries,
the ocean's acidity has increased 30 percent and, as a result,
carbonate concentrations have fallen by 16 percent.
If this trend continues, many marine animals and plants
that depend on calcium carbonate shells and skeletons won’t survive.
Our economy and health is tied to these organisms,
and ensuring the survival of shellfish is one of the many goals of PMEL's Carbon Group.
Oyster larvae, for example, will die if exposed to acidic ocean conditions
because they can't build their shells and settle out.
Real-time monitoring indicates when water conditions are favorable,
and oyster farmers can plan accordingly when to flush their tanks.
As PMEL's Carbon Group continues to collect data on ocean carbon
using traditional ships and buoys,
it is also advancing its capabilities for measuring ocean acidification
using wave-powered drones.
These autonomous systems, equipped with a host of scientific instruments,
travel across the ocean without burning a drop of fuel,
and collect swathes of data that were otherwise much more expensive to gather.
In the face of a changing world,
PMEL continues to study local and global changes in ocean chemistry and climate,
providing valuable information to help society better adapt to the future.