Backward trajectory showing the path the air took to arrive at Baring Head

Example of very clean air arriving at Baring Head.

Various meteorological parameters, such as wind speed and direction, air temperature and relative humidity are also measured at Baring Head.  These parameters play an important role in helping to interpret the trace gas measurements.  Back trajectories, which describe the path followed by an air parcel backward in time, are another useful tool for interpreting the trace gas measurements since they provide information on the long-range transport to the measurement site.