Chilbolton Facility for Atmospheric and Radio Research (CFARR): Gas analyser and Sonic anemometer data
A sonic anemometer and a gas analyser measuring water vapour and carbon dioxide are co-located within a compound dedicated to measuring fluxes using the eddy covariance method at Chilbolton Observatory. The eddy covariance technique is an atmospheric measurement method used to calculate vertical turbulent fluxes within the atmospheric boundary layer. This is the lowest region of the troposphere and is usually well mixed, particularly during daylight hours, due to convective heating from the sun. It is this motion in the lower troposphere that makes the technique possible.
In order to properly measure the turbulent properties of the atmosphere the measurements must be made at a high frequency - 20 Hz for the Chilbolton Observatory system.
A sonic anemometer measures the 3 orthogonal components of the wind velocity by measuring the changes in the time of flight of sonic pulses between 3 transmitter/receiver pairs as a result of the air velocity.
A gas analyser measures the absorptance of radiation along a fixed path and uses this to determine the concentration of a gas in air. For each gas the absorptance at 2 wavelengths is measured 152 times per second, one affected by that gas and the other unaffected.
There are more accurate instruments available for measuring water vapour and carbon dioxide (e.g. a relative humidity sensor for water vapour) but the benefit of the gas analyser is that it has a sufficiently fast response to resolve the rapid changes in concentration as a result of turbulence.
INSPIRE
Identification
- File identifier
- 3713e45f434e4e0bb5db6098dfba16e1 XML
- Resource type
- dataset
Online resource
Resource identifier
- Metadata Language
- English (en)
- Spatial representation type
- grid
Encoding
- Format
- Data are netCDF formatted
Projection
- code
- WGS 84
Classification of data and services
- Topic category
-
- Climatology, meteorology, atmosphere
Classification of data and services
Coupled resource
Coupled resource
Classification of data and services
Coupled resource
Coupled resource
Keywords
- GEMET - INSPIRE themes, version 1.0 ()
-
- atmospheric conditions
Other keywords
- Keywords
-
- CFARR
- gas analyser
- anenometer
Geographic coverage
Temporal reference
Temporal extent
Temporal extent
- Dataset Reference Date ()
- 2009-07-29T11:00:00
- Dataset Reference Date ()
- 2009-07-29T11:00:00
Quality and validity
- Lineage
- Data are collected by the Chilbolton Facility for Atmospheric and Radio Research (CFARR) before being checked by the instrument scientist and then delivered for archiving with the data centre.
Conformity
Conformity
Conformity
Conformity
Conformity
Conformity
Restrictions on access and use
Responsible organization (s)
Contact for the resource
- Organisation name
- Unavailable
- Unavailable
- Organisation name
- NCAS British Atmospheric Data Centre (NCAS BADC)
- badc@rl.ac.uk
- Organisation name
- NCAS British Atmospheric Data Centre (NCAS BADC)
- badc@rl.ac.uk
- Organisation name
- Unavailable
- Unavailable
- Organisation name
- NCAS British Atmospheric Data Centre (NCAS BADC)
- badc@rl.ac.uk
- Organisation name
- NCAS British Atmospheric Data Centre (NCAS BADC)
- badc@rl.ac.uk
Responsible organization (s)
Contact for the resource
- Organisation name
- Unavailable
- Unavailable
- Organisation name
- NCAS British Atmospheric Data Centre (NCAS BADC)
- badc@rl.ac.uk
- Organisation name
- NCAS British Atmospheric Data Centre (NCAS BADC)
- badc@rl.ac.uk
- Organisation name
- Unavailable
- Unavailable
- Organisation name
- NCAS British Atmospheric Data Centre (NCAS BADC)
- badc@rl.ac.uk
- Organisation name
- NCAS British Atmospheric Data Centre (NCAS BADC)
- badc@rl.ac.uk
Metadata information
Contact for the metadata
- Organisation name
- NCAS British Atmospheric Data Centre (NCAS BADC)
- badc@rl.ac.uk
- Metadata Date
- 2024-03-25T00:50:21
- Metadata Language
- English (en)