Florence Bascom Geoscience Center Seminar Series - August 1, 2019

Release Date:

Please join us for a guest presentation by Emiliano G. Santin on Thursday, August 1st. 

 

Methane Distribution in the Water Column of three high Arctic fjords in West Spitsbergen

Emiliano G. Santin
Ulster University, Northern Ireland and University Centre in Svalbard  

"Methane is an important greenhouse gas which plays a keyrole in the climatic feedback system. Waters in the Arctic Ocean are oversaturated with respect to methane. Data collected in 2019 in three high Arctic fjords in West Spitsbergen indicate a strong correlation between CH4 concetrations and the spatial distribution of pockmarks (depresions on the seabed). Methane concetration with values >40nmol L-1 were observed below the pycnocline in the deep sections of Van Mijenfjorden, Templefjorden, and Nordfjorden. Surface values of 10 to 20nmol L-1 denote that the CH4 concentration gradient is driven by the pycnocline that restricts vertical gas transport. The δ13CCH4 isotopic signature for samples obtained below the pycnocline (ranging from -47‰ to -45‰ VPDB) suggest methane gas depleted in C13 of thermogenic origin. The results stress the relevance of localized water mass properties and close relation between the spatial distribution of pockmarks and methane concentration in Arctic fjords."

 

Date: 11:00 AM ET, Thursday, August 1, 2019

Where: USGS National Center, Reston VA, Room 3C129

GS Talk: https://gstalk.usgs.gov/755736

Phone: 703-648-4848 Code:755736