Abstract/Description/Artist Statement
Brownification is when water bodies turn brown over time. It occurs due to high amounts of color-dissolved organic matter (CDOM). CDOM is organic material, such as decaying leaves and organisms, that leaches into the water column like tea. It absorbs ultraviolet and blue light more than red light, causing the water to appear brown. After comparing surveys from 1987 and 2018, scientists discovered the Adirondack lakes underwent brownification as they recovered from acid rain. However, while increased CDOM can signify an ecosystem’s recovery, it can also hinder seagrass growth. Although scientists have studied this phenomenon in lakes, estuaries have not received the same consideration. In this study, we aimed to determine whether the Chesapeake Bay is also experiencing brownification over time. To accomplish this, we used data taken from 1999 to 2024 from the Chesapeake Bay Program website. We graphed total suspended solids (TSS) and light attenuation (KD) from fifteen stations in the middle of the Chesapeake Bay and used the y-intercepts from these graphs as proxies for CDOM, plotting these values over time. To verify the methodology, we sampled four stations in the Lafayette River for KD, TSS, and CDOM. In the Chesapeake Bay, eight of the fifteen stations experienced an increase in estimated CDOM from past years (1999-2003) to recent years (2020-2024). Overall, CDOM estimates generally fluctuated at each station every year.
Keywords: Oceanography, CDOM, Brownification, Acid Rain, Estuaries, Chesapeake Bay, Water Clarity
Faculty Advisor/Mentor
Jessie Turner
Faculty Advisor/Mentor Email
jturners@odu.edu
Faculty Advisor/Mentor Department
Ocean and Earth Sciences
College/School Affiliation
College of Sciences
Student Level Group
Undergraduate
Presentation Type
Poster
Is the Chesapeake Bay Browning?
Brownification is when water bodies turn brown over time. It occurs due to high amounts of color-dissolved organic matter (CDOM). CDOM is organic material, such as decaying leaves and organisms, that leaches into the water column like tea. It absorbs ultraviolet and blue light more than red light, causing the water to appear brown. After comparing surveys from 1987 and 2018, scientists discovered the Adirondack lakes underwent brownification as they recovered from acid rain. However, while increased CDOM can signify an ecosystem’s recovery, it can also hinder seagrass growth. Although scientists have studied this phenomenon in lakes, estuaries have not received the same consideration. In this study, we aimed to determine whether the Chesapeake Bay is also experiencing brownification over time. To accomplish this, we used data taken from 1999 to 2024 from the Chesapeake Bay Program website. We graphed total suspended solids (TSS) and light attenuation (KD) from fifteen stations in the middle of the Chesapeake Bay and used the y-intercepts from these graphs as proxies for CDOM, plotting these values over time. To verify the methodology, we sampled four stations in the Lafayette River for KD, TSS, and CDOM. In the Chesapeake Bay, eight of the fifteen stations experienced an increase in estimated CDOM from past years (1999-2003) to recent years (2020-2024). Overall, CDOM estimates generally fluctuated at each station every year.
Keywords: Oceanography, CDOM, Brownification, Acid Rain, Estuaries, Chesapeake Bay, Water Clarity