1. Fall 2010 Nikki Byrd

2. What is turbidity? Measure of water clarity Degree to which water is scattered and absorbed Causes  Heavy rainfall, storms  Algal blooms  Flocculation in estuaries Waste discharge Run-off Land changes Native vegetation and agriculture POM/CDOM

3. What is turbidity?

4. Why does turbidity matter? High turbidity effects Drinking water Correlation with high levels of pathogens Reduced light penetration Increased K d Photosynthesis Dissolved oxygen Water temperature Dissolved oxygen

5. Measuring turbidity Secchi disk Accuracy Nephelometers Common Measures scattering 90° from an incident beam of light Scattering is proportional to turbidity Relative units: NTU More scattering = higher turbidity

6. Measuring Turbidity

7. Measuring turbidity

8. Measuring Turbidity

9. Cruise 1 Turbidity

10. Cruise 2 Turbidity

11. Cruise 1 v. 2008 LCFRP

12. Cruise 2 v. 2008 LCFRP

13. Cruise 1 v. Class Averages

14. Cruise 2 v. Class Averages

15. Turbidity v. Surface Salinity- Cruise 1 H B M18

16. Turbidity v. Deep Salinity-Cruise 1

17. Turbidity v. Surface Salinity- Cruise 2

18. Turbidity v. Deep Salinity-Cruise 2

19. Turbidity v. K d -Cruise 1

20. Turbidity v. K d -Cruise 2

21. Conclusions Cruise 1 Higher than LCFRP No correlation with class average Cruise 2 Higher than LCFRP Close to class average Turbidity maximum around M 35, M42 for 1 st cruise, M54 for 2 nd cruise Decrease with salinity Dilution Direct relationship with K d for both cruises, surface and deep