1 / 14

Residence Times in Texas Bays: 1975 - 2000

Residence Times in Texas Bays: 1975 - 2000. Laura Chu UT Marine Science Institute CE 394K – Surface Water April 26, 2005. Background. Residence time Why Study Inflows? Climate change Water Balance in Texas Constant vs. “flashy” system. Residence Time.

mandell
Télécharger la présentation

Residence Times in Texas Bays: 1975 - 2000

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Residence Times in Texas Bays: 1975 - 2000 Laura Chu UT Marine Science Institute CE 394K – Surface Water April 26, 2005

  2. Background • Residence time • Why Study Inflows? • Climate change • Water Balance in Texas • Constant vs. “flashy” system

  3. Residence Time • Estimate of the rate at which a volume of water moves through a bay. • Several methods to compute • Tidal-Prism method • Freshwater Fraction method

  4. Tidal Prism Method • Method based on changes in estuarine volume due to tides INSUFFICENT DATA • Officer (1976)

  5. Fresh-Water Fraction Method • Uses the salinity to calculate the residence time. • Assumptions • Hydrography • Constant bay volume

  6. Hypothesis • Ho1: Variation in freshwater inflows does not change the turnover time for Texas Bays • Ho2: El Niño has no effect in changing the rate of turnover in Texas Bays

  7. Inflows Monthly for 6 bays & estuaries TXWDB: 1941-2000 Salinity Monthly on a grid TXPWD: 1975 – present Volume of water CRWR – G. Ward El Niño SOI index Estuaries & Bays Sabine Trinity / Galveston Guadalupe / San Antonio Lavaca / Matagorda Mission - Aransas Nueces/Corpus Christi Data

  8. Methodology Salinity Water Balance Bay Volumes Residence Time Equations SOI Index Analyze data Hydrography GIS mapping

  9. Residence Times and Latitude

  10. North – South Differences

  11. SOI Index Values

  12. Effects of El Niño on Residence Times

  13. Some Conclusions • Seasonal freshwater inflows drive changes in residence times in Texas • Hypersaline conditions • No overall long-term trend • No significant El Niño effects

  14. Future Work & Questions • Relating inflow modeling to species abundance and ecosystem health • Effects of hydrography • Visualizing data in GIS • Implications for controlled flow regimes

More Related