Western Channel Observatory

NERC National Capability of the Plymouth Marine Laboratory and Marine Biological Association


Welcome to the Western Channel Observatory Website

L4 E1 map

What is the Western Channel Observatory?

The Western Channel Observatory (WCO) is an oceanographic time-series and marine biodiversity reference site in the Western English Channel. In situ measurements are undertaken weekly at coastal station L4 and fortnightly at open shelf station E1 using the research vessels of the Plymouth Marine Laboratory and the Marine Biological Association. These measurements are complemented by PML's recognised excellence in ecosystem modelling and satellite remote sensing science. By integrating these different observational disciplines we can begin to disentangle the complexity of the marine ecosystem.

From photons to fish, from seconds to centuries ...

The WCO measures several key parameters important to the functioning of the marine ecosystem such as light, temperature, salinity and nutrients. Station L4 has some of the longest time-series in the world for zooplankton and phytoplankton, and fish trawls have been made by the MBA for a century. Station E1 has a hydrographic series dating from 1903. These long series are complemented by hourly measurements made at our moorings situated at both stations. These can elucidate changes not captured by the routine weekly sampling.

Learn more

WCO moorings

PML operates and develops two scientific buoys at L4 and E1. These produce data every hour allowing short duration events, such as inputs from the Tamar estuary to be captured. The data are also used by the UK Met Office for operational oceanography applications.

Satellite data

PML operationally processes satellite derived fields of sea-surface temperature and ocean colour, which can be used to derive chlorophyll. These data allow the point measurements at L4 and E1 to be set in a wider context.

Ecosystem modelling

The western English Channel is a useful test area for developing ecosystem models. Data from the WCO are used to develop, parameterise and validate models and ideas.

Benthic survey thumbnail

Benthic survey

The unique and comprehensive Benthic survey of Plymouth Sound and the environs of L4 and Rame Head, started under Oceans 2025, is continuing as part of the WCO.


Marine Values?

VALMER is a European-funded project which is investigating how providing monetary values for marine ecosystem services can support effective marine planning and management.


Atmospheric Chemistry Observatory

PML has recently setup an Atmospheric Observatory at the mouth of Plymouth Sound: an ideal position for monitoring the impact of anthropogenic and natural sources of trace gases and their fluxes.

About Us

The WCO is a partnership between the Plymouth Marine Laboratory and the Marine Biological Association.

How are we funded?

The core work of the WCO is funded as part of the UK Natural Environment Research Council's National Capability.

Contact Information

For more details about the WCO please contact:

Dr Tim Smyth
Western Channel Observatory
Plymouth Marine Laboratory
Prospect Place
email: tjsm@pml.ac.uk