Title:
The Future of Giant Kelp Along the West Coast of North America Due to Rising Sea Surface Temperatures
Author(s):
Josh Ward
Author Email:
jward4@unca.edu
Department:
ATMOSPHERIC SCIENCES
Faculty Mentor(s):
Elaine Godfrey
Abstract / Summary:
Anthropogenic carbon dioxide (CO2) emissions play a large role in heating the planet. The oceans act as a sink for atmospheric CO2, reducing this greenhouse gas concentration within our atmosphere. Within the ocean, Giant kelp (Macrocystis pyrifera) acts as a sink for oceanic CO2 through the process of photosynthesis. A recent estimate suggests that macroalgae, including kelp, are responsible for approximately three percent of annual CO2 sequestration on a global scale. In addition to CO2 sequestration, kelp also plays a vital role in providing ecosystems for marine life and is an ingredient in many of the products we use. Previous research has proven that kelp biomass and Net Primary Production (NPP) are directly related, and kelp biomass is readily retrieved using high resolution remote sensing from Landsat-8 and Sentinel-2. Additional research demonstrates that kelp biomass (and therefore NPP) is significantly correlated to availability of nitrate, and that nitrate is strongly correlated with sea surface temperature. While giant kelp appears to be somewhat resistant to short-term marine heatwaves, recent publications also identify 24°C as a key threshold beyond which kelp cannot survive in the California Current System. With SST continuing to increase due to global warming, climate models can be used to predict how the distribution of giant kelp will react to future conditions. We show that by the end of the century, suitable kelp habitat will decrease substantially, resulting in a potentially significant reduction of natural carbon sequestration and will result in massive loss of habitat from these foundational species.
Publication Date:
May-14-2024
Documents: