Trinidad Head

The Trinidad Head station is located atop Trinidad Head (elevation ~120 meters) on the remote north coast of California, approximately 30 km north of Eureka.

The AGAGE operates two in-situ instruments there. The GC-MD instrument started measuring atmospheric CFC-11, CFC-12, CFC-113, CH3CCl3, CCl4, N2O, CH4, and CHCl3 in 1995. Air samples are collected from a tower used by the US Coast Guard for marine radio communications. The Medusa GC-MS instrument which measures more than 50 greenhouse gases and ozone depleting substances was installed in May 2005.

NOAA’s Global Monitoring Division also measures a range of ozone depleting substances and (until 2017) greenhouse gases at Trinidad Head.

Station designation: 



41.0541º N, -124.151º E

Station elevation: 

107 meters above sea level

Air intake elevation: 

15 meters above ground level

Station PI: 

Prof. Ray F. Weiss (; Dr. Jens Mühle (

Station manager: 

Randy Dickau

Station team: 

Jooil Kim, Chris Harth, Roland Schmidt, Jen Gonzalez

Postal address: 

Dr. Jens Mühle, Mail Code 0244
Scripps Institution of Oceanography
La Jolla, California, 92093

Station funding: 

AGAGE operations at Trinidad Head are funded by the National Aeronautics and Space Administration (NASA) in the USA.