Remote Sensing of Particle Backscattering in Chesapeake Bay: A 6-year SeaWiFS Retrospective View

David G. Zawada, Chuanmin Hu, Tonya Clayton, Zhiqiang Chen, John C. Brock, Frank E. Muller-Karger

Research output: Contribution to journalArticlepeer-review

Abstract

Traditional field techniques to monitor water quality in large estuaries , such as boat-based surveys and autonomous moored sensors, generally provide limited spatial coverage. Satellite imagery potentially can be used to address both of these limitations. Here, we show that satellite-based observations are useful for inferring total-suspended-solids (TSS) concentrations in estuarine areas. A spectra-matching optimization algorithm was used to estimate the particle backscattering coefficient at 400 nm, b bp (400), in Chesapeake Bay from Sea-viewing Wide-Field-of-view Sensor (SeaWiFS) satellite imagery. These estimated values of b bp (400) were compared to in situ measurements of TSS for the study period of September 1997–December 2003. Contemporaneous SeaWiFS b bp (400) values and TSS concentrations were positively correlated ( N = 340, r 2 = 0.4, P < 0.0005), and the satellite-derived b bp (400) values served as a reasonable first-order approximation for synoptically mapping TSS. Overall, large-scale patterns of SeaWiFS b bp (400) appeared to be consistent with expectations based on field observations and historical reports of TSS. Monthly averages indicated that SeaWiFS b bp (400) was typically largest in winter (>0.049 m −1 , November–February) and smallest in summer (<0.031 m −1 , June–August), regardless of the amount of riverine discharge to the bay. The study period also included Hurricanes Floyd and Isabel, which caused large-scale turbidity events and changes in the water quality of the bay. These results demonstrate that this technique can provide frequent synoptic assessments of suspended solids concentrations in Chesapeake Bay and other coastal regions.

Original languageAmerican English
JournalEstuarine, Coastal and Shelf Science
Volume73
DOIs
StatePublished - Jan 1 2007

Keywords

  • water quality
  • remote sensing
  • light backscattering
  • suspended particulate matter
  • ocean color
  • SeaWiFS
  • Chesapeake Bay

Disciplines

  • Life Sciences

Cite this