Depth dependence and intra-tidal variability of Suspended Particulate Matter transport in the East Anglian plume

- An observation based estimate of transport in the East Anglian plume yields a net eastward transport.
- Within a tidal cycle, both stratification and the SPM concentration profiles vary strongly in the East Anglian plume.
- Residual transports of SPM are calculated for the centre of the plume.
- In-situ measurements and remote sensing correspond qualitatively, but the latter is lower by about a factor of two.

In order to derive an estimate of the net transport of Suspended Particulate Matter (SPM) in the East Anglian plume, we carried out a measurement campaign along two cross-sections within the plume. Selected stations were visited repeatedly to resolve the tidal cycle. By measuring profiles of currents and optical backscatter (from which SPM concentrations were estimated, via samples), both gross and net transports can be calculated, as well as intra-tidal and vertical variability. For the centre of the plume, we find a net transport of about 13millionkg over a tidal cycle. A comparison is made with maps of near-surface concentration of SPM from optical remote sensing. Some discrepancy is found in the values (of about a factor of two), but the spatial pattern agrees qualitatively.