Instrument(s): PREDE POM01-L sunphotometer. June 2001 - March 2008 (Unknown serial number); August 2009 - December 2023 Serial Number PS08015
Manufacturer / Distributor: Kipp and Zonen (UK)
Date of installation: 2001 - 2023

Location of instrument: Roof of PML Prospect Place building
Address: PML, Prospect Place, Plymouth, Devon, UK, PL1 3DH
Latitude: 50.3659 N
Longitude: 4.1477 W
Height: 60 m ASL

Website: https://www.westernchannelobservatory.org.uk/sunphotometer/index.php

Aligned Funded projects:
1) NERC National Capability: Western Channel Observatory (https://www.westernchannelobservatory.org.uk)
2) NERC Cross Centre National Capability: ACSIS

Also associated with NASA AERONET and CIMEL sunphotometer sited at Rame Head (until 2013) and PML (since 2014)
https://aeronet.gsfc.nasa.gov/new_web/draw_map_display_aod_v3.html and search Rame_Head

Description of operation:
The instrument operates at 7 wavelengths (315, 400, 500, 670, 870, 940 and 1020nm) and scans at pre-set angles away from the solar disk to determine, using the inversion code of Nakajima et al. (2006), various properties of tiny particles called aerosols within the atmospheric column. From these measurements useful atmospheric aerosol parameters such as the Aerosol Optical Thickness (AOT), aerosol size distribution and single scattering albedo can be calculated. Marine aerosols tend to be bigger (D > 1µm) than those generated over the land (0.01 < D < 1µm) and are of a different chemical composition; marine aerosols are salt particles whereas terrestrial aerosols are sulphate compounds.