Shelfwide Cruises
The Issue. The scientific work for the commonly name ‘Dead Zone’ is hypoxia or low oxygen. The second largest zone of hypoxia in the world’s coastal waters is found in the Gulf of Mexico adjacent to the Mississippi River system. Important commercial and recreational fisheries are impacted as reduced oxygen levels force fish, shrimp and crabs from the area. Animals that cannot move away die. Fresh water and nutrients from the Mississippi lead to the annual formation of the hypoxic waters, and increasing nutrient loads beginning in the 1950s are responsible for the worsening oxygen conditions since then.
Mapping the extent of hypoxic water (< 2mg/L) across the Louisiana and Texas inner to mid continental shelf, along with associated physical, chemical and biological parameters. Associated rate measurements of biogeochemical processes.
Disclaimer: All data displayed on this cruise website are the exclusive property of Nancy Rabalais and Cassandra Glaspie. The data are being displayed in real-time and have not been quality controlled.
- The final dissolved oxygen data will be corrected, as necessary, from linear regression with the Winkler titrations over a range of 0.22 to 8.43 mg/L. Initial observations indicate correction, but the f-factor for the Winkler standard remains to be verified. Any corrected data will be reflected in other derived measurements.
- Salinity data not yet verified with PortaSal samples.
- CTD data remain to be post-processed with ALIGN CTD to be applied.
- Instrumentation was calibrated pre- and post-cruise according to manufacturer’s specifications and standard method procedures were applied for several variables, not yet calculated, according to several LUMCON EPA-approved Quality Assurance Project Plans.
- Data collected as part of process studies remain to be analyzed and synthesized.
- Final QA/QC’d data will be submitted to NOAA NODC within two years of collection.