Hypoxia -Rain/River Flow

Here is the 1st week’s show, Hypoxia Week 1: Rain/River flow!


I’m McKensie Daugherty your host for On the Ocean. Flooding in Texas is at an all-time record this year, and as a result the rivers keep swelling. This means that rivers including the Brazos, Trinity, Colorado, Sabine, and Guadalupe will be pouring the rainwater straight into the Gulf of Mexico. Because of this increase in freshwater, Texas will experience a wider and potentially longer lasting dead zone in the Gulf of Mexico. Dead zones (also known as hypoxia) are areas in the deeper ocean layers that are oxygen depleted, and because of this they can be harmful to the ocean organisms that need oxygen to survive. The freshwater contributes to the creation of a dead zone because the freshwater is lighter and will stay at the surface, while the salty ocean water is heavier and will stay below the freshwater layer. The deeper layer is cut off from the oxygen in the atmosphere and will begin to lose its dissolved oxygen in the water. But it’s not just the large amount of rain that contributes to dead zones in oceans, the timing of the flooding is also causing these dead zones to persist. For example, when there is a large amount of rain in Dallas it will take around a month for water to reach the Gulf. Since this year’s flooding has been an ongoing event, the dead zones will continue to develop and possibly expand. Dead zones can be dissipated through strong winds and waves, usually caused by storms or hurricanes. This is due to the physical force of the breaking up of layers in the ocean, the dead zone is currently predicted to span over 5,000 miles this year in the Northern Gulf of Mexico. This has been On the Ocean, a program made possible by the Department of Oceanography and a production of KAMU-FM on the campus of Texas A&M University in College Station. For more information and links, please go to ocean.tamu.edu and click On the Ocean.


More Information and Links:

Contributing Professor Dr. Steve DiMarco:


Mechanisms Controlling Hypoxia:


Page for Gliders that gather Hypoxia data:


Glider Data from Hypoxia :

Water density -Smaller means fresher and less salty. The layers of freshwater over salty water that aren’t mixing well shows areas of Hypoxia


Dissolved Oxygen -Blue colors are low, meaning Hypoxia


Using data like this, we can track Hypoxia over distances in the Northern Gulf of Mexico.


Thanks for listening!