In a recent satellite image captured in 2020, the aftermath of Hurricane Sally is clearly visible as tea-like "blackwater" permeates into South Carolina's Winyah Bay. The hurricane triggered severe flooding across various states, including South Carolina, resulting in the overflow of blackwater rivers that feed into the bay. The image, taken about two weeks after the hurricane made landfall, depicts an unsettling scene where the floodwaters carry an excess of colored dissolved organic matter (CDOM), staining the bay and eventually flowing into the ocean.

Winyah Bay, located near Georgetown, South Carolina, is a coastal estuary that receives water from four blackwater rivers: the Waccamaw River, the Pee Dee River, the Black River, and the Sampit River. These rivers pass through swamps, wetlands, and forests, where decaying vegetation releases chemicals like tannin, phenol, and humic acid. As a result, the water takes on a brown hue, similar to brewed tea, as described by NASA's Earth Observatory.

Hurricane Sally, which made landfall on September 16, 2020, with maximum winds of around 110 mph (177 km/h), brought heavy rainfall ranging up to 30 inches (76 centimeters) across several states, including South Carolina. The torrential rains caused widespread flash flooding, as reported by the National Weather Service. Due to the excessive precipitation, the floodwater accumulating CDOM significantly increased the levels in Winyah Bay, surpassing the average for that date by more than 50%, according to monitoring stations on October 1, when the satellite image was taken.

The overflowing CDOM-rich water ultimately made its way into the ocean, leading to reduced penetration of blue light and a rusty appearance when viewed from above. This change in available light has consequences for photosynthetic algae, such as phytoplankton, which may struggle to absorb red light and carry out photosynthesis. Tammi Richardson, an oceanographer at the University of South Carolina, warned that this disruption could have significant cascading effects on the food webs within coastal ecosystems.

Despite the challenges posed by increased CDOM levels, some plankton species, such as cryptophytes and diatoms, have adaptations that enable them to thrive in blackwater conditions, as per NASA's Earth Observatory.

The satellite image serves as a reminder of the environmental impacts that extreme weather events can have on delicate ecosystems. Scientists and researchers will continue to monitor the effects of blackwater discharge on Winyah Bay and its associated coastal habitats, seeking to understand and mitigate the potential long-term consequences.

While the tea-like waters may gradually dissipate, the lasting ecological implications of Hurricane Sally's aftermath remain a concern for the coastal regions of South Carolina.