The ocean is a huge part of the carbon cycle on Earth. How much carbon it holds and what conditions cause it to release carbon are major factors when it comes to monitoring climate change. Now, scientists are taking a closer look at the ocean's carbon cycle.
In this latest study, researchers decided to see if they could quantify the mechanisms of the ocean's biological pump. This is a major component of the carbon cycle. This pump actually controls the transport of carbon from the well-lit upper ocean, called the euphotic zone, to the twilight zone, which is also known as the aphotic zone. In the twilight zone, a fraction of the exported carbon is then respired back as CO2.
Carbon in the atmosphere can be stored in soils, oceans and even in the Earth's crust. Any movement of carbon between these areas is called a flux. And quantifying this carbon flux is important for understanding the atmosphere's response to changing climates.
"Predicting how the ocean's carbon cycle changes in the future remains one of the greatest challenges in oceanography," said David Siegel, lead author of the new study and director of UCSB's Earth Research Institute. "EXPORTS combines modeling, satellite data and ship and robotic field sampling to assemble a comprehensive understanding of how carbon is processed by the world's oceans. The resulting data sets will be used to determine the implications for present and future climates."
The researchers estimated sinking flux, which is how much carbon reaches the ocean depths through the food web. However, the scientists still need a better way to understand active migration flux, which is when zooplankton moves from the depths to the surface and then back again. In fact, the researchers say that extensive fieldwork needs to be done in order to better understand the carbon flux within the ocean.
The findings reveal how best to go about better understanding the carbon cycle. More specifically, it shows what needs to be done in order to correctly estimate carbon flux, which could help scientists better estimate future climate change.
The findings are published in the March 2016 journal Frontiers in Marine Science.
