FIFE BASELINE SOIL MOISTURE DATA DOCUMENTATION: Site averaged data files:Summers of 1987, 1988, and 1989 (IFC-5 only). as data sets: Site Averaged Gravimetric Soil Moisture Data: Site Avg. Grav. Soil Mstr: 1987 (Betts) Site Avg. Grav. Soil Mstr: 1988 (Betts) Site Avg. Grav. Soil Mstr: 1989 (Betts) Site Avg. Grav. Soil Mstr: 87-89 (Betts) (composite of data for all 3 years) Site Averaged Neutron Probe Soil Moisture Data: Site Avg. Neut. Soil Mstr: 1987 (Betts) Site Avg. Neut. Soil Mstr: 1988 (Betts) Site Avg. Neut. Soil Mstr: 1989 (Betts) (9 days from July 25, 1989-August 2, 1989) Site Avg. Neut. Soil Mstr: 87-89 (Betts) (composite of data for all 3 years) ffo_sm.doc Date: June 14, 1996 First release KEY REFERENCE: Betts and Ball, 1997: FIFE surface climate and site-average data set 1987-1989, J. Atmos. Sci. (3rd FIFE special issue) In press. REVISION HISTORY: First Release: June 14,1996 ****We have no plans to revisit this data; but let us know of errors The SOIL MOISTURE SITE averages are of 2 kinds: 1) Gravimetric Values are at 2.5cm for the 0-5cm layer 7.5cm for the 5-10cm layer Multipying them by a mean bulk density of 1.1 gives a representative Volumetric soil moisture. Note that in papers prior to Betts and Ball 1996 (see Appendix) (Betts et al 1993, Betts and Ball 1995), I (AKB) used an incorrect volumetric conversion. 2) Neutron probe data together with a merged gravimetric values for the 0-5,5-10 cm layers, converted by FIS to a volumetric value, using individual sample density. These values are a profile down to 200cm if the tube went that deep (no rock) Source: Alan K. Betts and John H. Ball Atmospheric Research, RR#3, Box 3125, Pittsford VT 05763. akbetts@aol.com 802 483-2087 (voice) 802 483-6167 (FAX) JUNE 14 1996 release File names size (bytes) ffogrv87.dat 6511 ffogrv88.dat 7289 ffogrv89.dat 1029 ffo_grv.dat 16651 ffoneu87.dat 18179 ffoneu88.dat 18902 ffoneu88.dat 1440 ffo_neu.dat 40065 *** See also: FIFE Site Averaged AMS (Meteorology) Data as: Site Averaged AMS Data: 1987 (Betts) ffoams87.dat Site Averaged AMS Data: 1988 (Betts) ffoams88.dat Site Averaged AMS Data: 1989 (Betts) ffoams89.dat Site Averaged AMS Data: 1987-89 (Betts) ffo_ams.dat FIFE Site Averaged Surface Flux Data as: Site Averaged Surface Flux Data: 1987 (Betts) ffoflx87.dat Site Averaged Surface Flux Data: 1988 (Betts) ffoflx88.dat Site Averaged Surface Flux Data: 1989 (Betts) ffoflx89.dat Site Averaged Surface Flux Data: 1987-89 (Betts) ffo_flx.dat 1.0 Origin of Data The center of the FIFE 15x15 km site is close to 39.05þN, 96.53þW. The data was retrieved directly from the Oak Ridge DAAC (Thanks to Merilyn Gentry). All the originating data however should correspond to that CD-ROM Volume 1, dated May 22, 1994, in directories soilmstr\sm_grav and sm_neut 2.0 Description of data sets (table) This data set is a time series of daily values for the periods: ffogrv87.dat May 20, 1987- Nov 6, 1987 ffogrv88.dat Apr 11, 1988- Oct 21, 1988 ffogrv89.dat Jul 19, 1989- Aug 12, 1989 ffo_grv.dat May 20, 1987 - August 12, 1989 (composite of all 3 years data) Fields are: Day,SM25,SM25-k,SM25-sum,SM75,SM75-k,SM75-sum SM25,SM75 are gravimetric % soil moisture for soil layers 0-5,5-10cm Samples were averaged for each site,then each site was interpolated to give a value for each day. Then the sites were averaged for each day. SM25-k, sm75-k is a count of the sites in the average. SM25-sum, SM75-sum is the sum of the total no of independent measurements on that day. Thus when SM25-sum is blank, there were no measurements on that day at all; the value is pure interpolation, and attention should be paid to the rainfall data before using. ffoneu87.dat May 28, 1987 - November 6, 1987 ffoneu88.dat April 12, 1988 - September 29, 1988 ffoneu89.dat July 25, 1989 - August 02, 1989 ffo_neu.dat (composite of 1987, 1988, and 1989 data) These too were averaged at each site (which often had 5 tubes, interpolated to fill in missing days, and then all sites were averaged. Data levels are 200,180,160,140,120,100,80,60,50,40,30,20cm and the 2 volumetric values for 2.5 and 7.5 cm converted from gravemetric measurements For 20 and 100cm we have included a count (k) of sites and a sum of the actual no of measurements to indicate data density on that day. Again a blank means no actual observations; value is all interpolation. The 20cm level data is suspect.. range of neutron probe exceeds 20cm in dry soil. The 20cm data has different characteristics in 1987 to 1988; it is inconsistent with the profile in 87 but not in 88. I suspect a change of measurement protocol, but the documents show nothing so it is only hearsay. The 1989 neutron data is so infrequently sampled that the avereage should be used with caution. 2.1 Time index is Julian day 2.2 Stations Selected All data is included 2.3 List of Variables Table 1.1 Gravimetric Soil Moisture Variable Description Variable Name SAS Type* Variable Description/Units 1 Jul_Date 8 "Julian date (day of year 1-366)" 2 SM25 8 "Average % soil moisture at 0-5cm depth" 3 SM25_k 8 "Number of sites included in average soil moisture at 0-5cm depth (SM25)" 4 SM25_sum 8 "Sum of soil moisture measurements at 0-5cm depth" 5 SM75 8 "Average % soil moisture at 5-10cm depth" 6 SM75_k 8 "Number of sites included in average soil moisture at 5-10cm depth (SM25)" 7 SM75_sum 8 "Sum of soil moisture measurements at 5-10cm depth" 8 obs_date 8 "Observation date (mm/dd/yyyy)" 9 year 8 "Year" Table 1.2 Neutron Probe Soil Moisture Variable Description Variable Name SAS Type* Variable Description/Units 1 Jul_Date 8 "Julian date (day of year 1-366)" 2 SM200 8 "Average soil moisture at depth of 200cm" 3 SM180 8 "Average soil moisture at depth of 180cm" 4 SM160 8 "Average soil moisture at depth of 160cm" 5 SM140 8 "Average soil moisture at depth of 140cm" 6 SM120 8 "Average soil moisture at depth of 120cm" 7 SM100 8 "Average soil moisture at depth of 100cm" 8 SM100_k 8 "Number of sites included in average soil moisture at depth of 100cm (SM100)" 9 SM100sum 8 "Sum of soil moisture measurements at depth of 100cm" 10 SM80 8 "Average soil moisture at depth of 80cm" 11 SM60 8 "Average soil moisture at depth of 60cm" 12 SM50 8 "Average soil moisture at depth of 50cm" 13 SM40 8 "Average soil moisture at depth of 40cm" 14 SM30 8 "Average soil moisture at depth of 30cm" 15 SM20 8 "Average soil moisture at depth of 20cm" 16 SM20_k 8 "Number of sites included in average soil moisture at depth of 20cm (SM20)" 17 SM20sum 8 "Sum of soil moisture measurements at depth of 20cm" 18 SM7_5v 8 "Volumetric soil moisture for depth of 7.5cm converted from gravimetric measurements" 19 SM2_5v 8 "Volumetric soil moisture for depth of 2.5cm converted from gravimetric measurements" 20 SM2_5vk 8 "Number of gravimetric measurements at 2.5cm included in volumetric conversion" 21 obs_date 8 "Observation date (mm/dd/yyyy)" 22 year 8 "Year" * SAS Type: 8 = Numeric Variable SAS Type: $ n = Character Variable of Length n The data definition file (*.def) accompanying each data set provides the exact list of variables included in the data set. The data files are comma delimited ASCII files and contain a header line listing the data fields included in the file. The comprehensive list of variables above is provided for general information only. 3. Data Quality Irregularity of sampling is the biggest problem with the soil moisture data. During dry spells and between IFC's sampling was less frequent, and this smooths the timeseries considerably. Acknowledgment. You may use these files freely. Please send me (Alan Betts) an e-mail if you do, so I can notify you of any updates. Please notify me of any errors you find. This data processing was supported by NASA under Contract NAS5-32356 to Alan Betts, and an acknowledgment of the work (both by the original PI's and by myself) that went into the data collection and the production of these files would be appreciated in publications based substantially on them. The FIFE CD-ROM can be cited as Strebel et al (1994). 4.References. Betts, A.K., J.H. Ball, and A.C.M. Beljaars, 1993: Comparison between the land surface response of the European Centre model and the FIFE-1987 data. Q.J.R.M.S., 119, 975-1001. Betts, A.K. and J.H. Ball, 1994: Budget analysis of FIFE-1987 sonde data. J.G.R., 99, 3655-3666. Betts, A.K. and J.H. Ball, 1995: The FIFE surface diurnal cycle climate. J.G.R. 100, 25679-25693. Betts A. K. And J. H. Ball, 1997: FIFE surface climate and site-average data set: 1987-1989. (FIFE special issue 3 J. Atmos. Sci. in press) Strebel, D. E., D. R. Landis, K. F. Huemmrich, and B. W. Meeson, 1994: Collected data of the First ISLSCP Field Experiment, in Surface Observations and non-image data sets., Vol 1, CD-ROM, NASA GSFC, Greenbelt, MD 20771 The First FIFE special issue in JGR (November, 1992) contains many important refs by the PI's who collected this data.