UK SOLAS Project: Cape Verde Observatory

This page supplements the main UK SOLAS programme page with details that relate only to the Cape Verde Observatory project.

* Introduction

The UK SOLAS Cape Verde Atmospheric Observatory (16.848N, 24.871W) exists to advance understanding of climatically significant interactions between the atmosphere and ocean and to provide a regional focal point and long-term data context for SOLAS field campaigns. The observatory is based on Calhau Island of So Vicente, Cape Verde in the tropical Eastern North Atlantic Ocean, a region which is data poor but plays a key role in atmosphere-ocean interactions of climate-related and biogeochemical parameters including greenhouse gases. It is an open-ocean site that is representative of a region likely to be sensitive to future climate change, and is minimally influenced by local effects and intermittent continental pollution. Measurements began at the site in October 2006.

* Availability of data

MeasurementInstrument DescriptionBADC File name
MeteorologicalThe instrumentation includes wind direction, wind speed, temperature and relative humidity sensors at two heights, and also measurements of atmospheric pressure and radiation. cv-met-cambell and cv-met-webdaq
Ozone (3m)Model 49C Photometric Analyser, a UV absorption technique with an accuracy of 1 ppbV. cv-tei-o3
COVacuum ultraviolet fluorescence CO analyser (Aerolaser 5001). It is designed for fast response measurements and has a detection limit of <1 ppbv. cv-aerolaser-co
NOxyAir Quality Design NOxy instrument is a single channel, chemiluminescence NO detector with a photolytic NO2 converter (diode based blue light converter (BLC) Droplet Measurement Technologies) and a Molybdenum catalyst NOy converter (Thermo Electron Industries). The detection limits for a 10 minute data cycle are ~3 pptV, 6pptV, 3pptV for NO, NO2 and NOY respectively. cv-noxy
Ozone (10m)Ozone (10m):-Thermo Model 202 UV Absorption manufactured by 2B Technologies. This instrument also has an accuracy of 1 ppbV. cv-2b-o3
VOCDual channel gas chromatograph with dual flame ionisation detection (GC-FID) measures C2-C8 Non-methane hydrocarbons and also C2-C4 oxygenated VOC. It works by trapping the VOC out of the air onto a carbon adsorbent trap at -20C with subsequent desorption at 350C into a helium carrier flow. This instrument has a time resolution of 1 hour. cv-dc-gc-fid
IO, BrO, NO3 and various other speciesLong-path Differential Optical Absorption Spectrometer (LP-DOAS) measures scattered sun light to determine the amount of various trace gases along the 6km light path through the atmosphere. The basic quantity observed by the instrument is the integrated concentration of the trace gas along the light path. cv-lp-doas
IO, BrO and various other speciesMulti-Axis Differential Optical Absorption Spectrometer (MAX-DOAS) works in a similar way to the LP-DOAS but observes scattered sunlight along different lines of sight, in particular at different elevation angles. cv-max-doas
HalocarbonsGas chromatograph with mass spectrometric detection cv-gc-ms

The BADC is also providing back trajectories from Cape Verde. These are 5 day back trajectories using the 2.5 degree ECMWF archive data. They are daily at 12:00. The endpoint of each trajetory is at 950 hPa above the Observatory as using a lower height can lose trajectories into the ground. Information and help is available for the BADC Trajectory Service

* Access to data

DataAccess rulesHow to accessLink to data
Cape Verde archive Restricted to project participants for 1 year following collection and UK SOLAS participants for a further year, see details in the UK SOLAS Data Protocol. Once public, requirements will continue to apply to publications based on Cape Verde data. Apply UK SOLAS Cape Verde archive
Cape Verde ECMWF back trajectories Signature of the NERC - Met Office Agreement now or at some point in the past. Apply Plotting and download

To make any of the applications above you need to register as a BADC user. If you have previously registered but forgotten your user ID and/or password, please contact the BADC helpdesk at

Also see the log of changes to the dataset, such as file revisions, at Cape Verde data log page.

* Instructions to data providers

Details of formats, filenames and how to submit data are given on the UK SOLAS programme page .

* Links

* Who to contact