Exploring the Whiting Features of SW Florida Through Remote Sensing Techniques and Field Measurements.

Jacqueline Long, University of South Florida, College of Marine Science, St. Petersburg, FL, United States and Chuanmin Hu, University of South Florida Tampa, Tampa, FL, United States
Floating patches of water containing high levels of calcium carbonate have been referred to as “whitings” for their bright spectral color. These in-water features are most noticeably found in the Bahama Banks region, but also in the Persian Gulf, and fresh water lakes. Although whitings have been studied for nearly a century, their process of formation is still hotly debated, whether these are the result of resuspended sediment by turbulent boundary conditions, biogenic precipitation by phytoplankton, the result of local chemistry, or something else, is still unknown. Whitings are also recurrent features, occurring throughout the year, usually with a seasonal preference. Individual events can be up to 250km2 and last for longer than one month. With such magnitude, it is important to finally understand the causes of these events, as well as their potential proxies. Though recurring, whitings are also hard to predict. Our region of interest holds newly documented whitings in a remote location, offshore from Everglades City, Florida. This study aims to combine remote sensing techniques with field measurements in order to understand a newly identified, recurring, in-water feature of SW Florida. Using daily MODIS images, a 10-year time series has been developed to evaluate the spatio-temporal variability of whitings in this area. The daily images available in near real-time also helped to plan field trips to take direct measurements of the whitings. Initial parameters were chosen based on long-standing hypotheses of whiting formation, such as those listed above, but also included spectral reflectance and backscattering as well as particle and CDOM absorption These were taken both inside and outside the whitings in order to better identify these features from remote observations. Our results provide the first study of whitings in SW Florida, adding a new multidisciplinary perspective to the world-wide phenomenon.