Message from Dave Hollinger (October 5, 1997): Hello AMERIFLUXERS - We will use the EUROFLUX raw data files ("gold files") for intercomparison of the flux software used at AmeriFlux sites. The data are available in a number of ways, either via ftp from their Euroflux home or via ftp from at CDIAC: ftp cdiac.esd.ornl.gov > anonymous > e-mail address > cd /pub/ameriflux/gold > ls > get .... NOTE: for the CDIAC-available files "GOLD.ZIP" (9.98 Megabytes) is the GOLD.ZIP. "gold.asc.Z" (10.78 Megabytes) is the same GOLD file, but the commas are removed (data in space-delimited columns) and rezipped in UNIX. 'Uncompress gold.asc.Z' will make it available as an ASCII file on a UNIX system. "gold.sas" (0.3 Kbytes) provides a SAS code illustration of data access to the unzipped gold-file. END NOTE. or via CD-ROM or zip drive from Bob Evans (e-mail: rse@christa.unh.edu). We have taken the original 1/2 hour files and concatenated them and applied a timestamp. I would hope that some groups could process these data and get back to me with results before the St. Louis meeting which starts: Oct. 28, 1997 at 10:00 AM - ends : Oct. 29, 1997 at 5:00 PM. - Dave "GOLD.ZIP" (9.98 Megabytes) Is a PC-zipped, comma delimited ascii data file (> gold.raw) consisting of hourmin, seconds, u, v, w, speed of sound (m/s), CO2 (umol/mol), and H2O (mmol/mol). It is a concatenation (plus time stamp) of the half-hourly EUROFLUX "Gold" files contained in serie2.zip provided by Marc Aubinette. The ftp address of the individual files is: ftp.fsagx.ac.be/pub/euroflux/ They are zipped (name : « serie2.zip »). There are 19 data files of ˝ h each containing u,v,w,ss (m/s), c (umol/mol) and h (mmol/mol) in ASCII, comma delimited. The files are successive and may be treated in one run. The period was selected in order to sweep across a large range of meteorological conditions (cloudy, sunny, night). ftp.fsagx.ac.be >anonymous >e-mail address > cd pub/euroflux > get serie2.zip (ought to get you 7088624 bytes) Marc provided the following information about the site and flux system. "The site is located in Vielsalm in the Belgian Ardennes (50° 18’ N , "6°00’ E). The region has a hilly topography with a 3% slope in the north westerly direction. The climate is temperate maritime (the coast is about 150 km from the site). See also EUROFLUX. The forested stand results from plantations established early this century. The vegetation consists of a mixture of coniferous and deciduous species. Pseudotsuga menziesii (Douglas fir) and Picea abies (spruce) are the predominant coniferous species, while Fagus sylvatica (beech) is the main deciduous species. The understorey vegetation mainly consists of mosses. The conifers are about 35 m tall and are mainly located to the North East of the instrument tower. The deciduous species are about 27 m and cover predominantly the Southern and Western side of the forest site. The golden files were measured with the wind from the NE. The footprint is thus essentially located in the Douglas area. Fluxes of CO2, water vapour and sensible heat were measured by an eddy correlation system installed on a tower at 40m height above the forest floor. The eddy correlation instruments consist of a fast response infrared gas analyser (model LI-6262, LI-COR Inc., Lincoln, NE, USA) and a three dimensional sonic anemometer (model SOLENT 1012R2, Gill Instruments, Lymington, UK). Air from above the canopy was drawn through an 8.0 m long and 4 mm diameter PTFE tube and then into the analyser. The pump (KNF NO22 AN18, Village Neuf, France) was installed downstream of the analyser and provided a flow rate of 6 lmin-1. Two Teflon filters (1 GELMAN ACRO 50, 1mm and 1 GELMAN SPIRAL CAP 0.2mm) were also placed upstream of the gas analyser in order to avoid dirtying of the optical chamber. The raw signals were recorded at a frequency of 20.8 Hz. ---------------------------------------------------------------------------- Marc AUBINET Dept Physics Faculté Universitaire des Sciences Agronomiques 8 av. de la Faculté B-5031 GEMBLOUX - BELGIUM Tel 32 81 62 24 88 Fax 32 81 61 45 44"