Ocean acidification

When: Wednesday October 9, 2019 at 1:00 PM ET

Presented by Richard Wahle, PhD. and Maura Niemisto of the University of Maine

Anthropogenic carbon released into the atmosphere is driving rapid, concurrent increases in temperature and acidity across the world’s oceans, most prominently in northern latitudes. The geographic range of the iconic American lobster (Homarus americanus) spans a steep thermal gradient and one of the most rapidly warming ocean environments. Understanding the interactive effects of ocean warming and acidification on this species’ vulnerable early life stages is important to predict its response to climate change on a life stage-specific and population level. This study investigated the interactive effects of ocean warming and acidification on the gene expression response of the planktonic post-larval lobster from southern New England. Using a full factorial experimental design, lobsters were raised in ambient and elevated pCO2 concentrations (400 ppm, 1200 ppm) and temperatures (16°C and 19°C). Overall, we identified 1,108 transcripts that were differentially expressed across treatments, several of which were related to stress response and shell formation. When temperature alone was elevated (19°C), larvae downregulated genes related to cuticle development; when pCO2 alone was elevated (1200 ppm), larvae upregulated chitinase as well as genes related to stress response and immune function. The joint effects of end-century stressors (19°C, 1200 ppm) resulted in the upregulation of those same genes, as well as cellulase, and the downregulation of calcified cuticle proteins, and a greater upregulation in genes tied to immune response and functioning. These first results of the impact of varying conditions on larval lobster gene expression suggest the existence of mechanisms to respond to stressors resulting from a rapidly changing environment.

Continue reading ‘Webinar: Gene regulatory response to end-century temperature and pCO2 in post-larval American lobster’

When: 4th October Time: 16:00 (GMT)

Oceanographer with doctoral studies in Coastal Oceanography at the School of Marine Sciences of the Autonomous University of Baja California and postdoctoral fellow at the Scripps Institution of Oceanography in San Diego, California. Dr. Hernandez is a specialist in Carbon Dioxide System in seawater and marine biogeochemistry. His research has focused on studying the role of coastal zones in the carbon cycle, including the effect of ocean acidification (OA) on marine ecosystems and its relationship with other stress factors such as hypoxia, climate change and CO2 flows in coastal regions. Dr Hernández-Ayón is a member of the IMECOCAL (Mexican Research of California Current) scientific committee and of the GOA-ON Executive Council. He is a representative of the Surface Ocean Lower Atmosphere Study (SOLAS) group in Mexico, serves as Coordinator of the Mexican Carbon Program (PMC), and is the Co-Chair of the Latin American Ocean Acidification Studies Network (LAOCA).

Continue reading ‘Webinar: pH measurements for acidification studies: what to do with available data and methods’