The data on this website is research level and subject to change. For further information please contact Marek Zreda at the University of Arizona: phone: +1 (520) 621 4072 email: marek@hwr.arizona.edu COSMOS generated data is available in three different levels. - Level 1 data is raw data from the probes. - Level 2 data is quality controlled and corrected for local effects. - Level 3 data estimates soil moisture from cleaned, corrected data. ------------------------------------------------------------------------------ LEVEL 1 Level 1 data contains raw counts of fast and thermal neutrons as well as probe diagnostics for quality control purposes. Neutrons are counted over a time period (usually one hour) and count levels are reported at the end of each period. Example level 1 data is as follows: YYYY-MM-DD HH:MM MODE UNMO PRESS TEM RH BATT UTC /hr /hr mb C % V 2010-07-21 03:20 1013 541 976.1 33 14 12.7 Where: YYYY-MM-DD is the end date (UTC) of the neutron count interval, when the neutron data are forwarded to the server and the counter reset. HH:MM is the end time (UTC) of the neutron count interval, when the neutron data are forwarded to the server and the counter reset. MODE is the fast neutron count over the preceding time interval, usually the difference in time between the given time and time on the previous row. MOD refers to moderated tube counts. UNMO is the thermal neutron count over the preceding time interval, usually the hour between the time given and time on the previous row. UNMO refers to unmoderated tube counts. PRESS is the atmospheric pressure (mb) inside the neutron probe box at the date and time given in columns 1 and 2. As the box is unpressurized, temporal changes in pressure should reflect local atmospheric changes. The pressure gauge is locally calibrated, but can in some instances be innacurate. TEM is the atmospheric temperature (degrees C) inside the neutron probe box at the date and time given in columns 1 and 2. As the temperature sensor is attached to the electrical circuitry of the box, it should not be used as a proxy for local atmospheric conditions. The temperature sensor is used as a probe diagnostic. RH is the relative humidity (%) inside the neutron probe box at the date and time given in columns 1 and 2. As the relative humidity sensor is attached to the electrical circuity of the box, it should not be used as a proxy for location atmopheric conditions. The relative humidity sensor is used as a probe diagnostic. BATT is the battery voltage (Volts) of the neutron probe at the date and time given in columns 1 and 2. The battery voltage is used as a probe diagnostic. All fields in Level 1 can be viewed by clicking on the 'Probe Diagnostics' link. ------------------------------------------------------------------------------ LEVEL 2 Level 2 data takes raw, Level 1 data and converts it to a format suitable for soil moisture computation. The data is quality controlled, so that records: (1) with fast neutron counts more than 20% different to previous counts, (2) with fast neutron counts less than 40% of the maximum count rate, (3) with fast neutron counts greater than the maximum count rate, (4) with probe voltages less than 10 V, are flagged and removed from future analyses. The numbers in brackets are flag values. Actual flag values for daa can be found by clicking on 'Level 1 Data' for any probe, and changing '.txt' in the URL to '.fla'. Alternately, flags are listed in the complete station database at http://cosmos.hwr.arizona.edu/Util/bystations.php Fast counts are then converted to standard counts to remove local effects. For standard counts we use the reference probe, located at San Pedro, Arizona (http://cosmos.hwr.arizona.edu/Probes/StationDat/002/index.php). Example Level 2 data is as follows: YYYY-MM-DD HH:MM MOD PROBE PRESS SCALE SANPE INTEN OTHER CORR ERR 2009-10-23 18:34 5996 0.800 1.087 06.901 2.486 1.000 1.000 1878 024 Where YYYY-MM-DD is the end date (UTC) of the neutron count interval, when the neutron data are forwarded to the server and neutron count reset. HH:MM is the end time (UTC) of the neutron count interval, when the neutron data are forwarded to the server and neutron count reset. MOD is the fast neutron count over the preceding time interval, quality controlled to be 60 +/- 1 minutes since the previous count. PROBE is the scaling factor to account for differences in the size/ composition of the probe from the San Pedro baseline probe. PRESS is the scaling factor to account for changes in pressure at the site of the probe, which changes cosmic ray intensity. SCALE is the scaling factor to account for differences in cosmic ray intensity as a result of the elevation/cutoff rigidity of the site where the probe is located. For more information, see: Desilets, D., and M. Zreda (2003), Spatial and temporal distribution of secondary cosmic-ray nucleon intensities and applications to in-situ cosmogenic dating, Earth Planet. Sci. Lett., 206, 21–42, doi:10.1016/ S0012-821X(02)01088-9. SANPE is the scaling factor at the San Pedro probe to account for differences in cosmic ray intensity at the San Pedro probe. INTEN is the scaling factor to account for temporal changes in cosmic ray intensity as a function of time. We acknowledge the NMDB database (www.nmdb.eu), founded under the European Union's FP7 programme (contract no. 213007) for providing data from the monitor Jung, supported by the Physikalisches Institut of the University of Bern and by the International Foundation High Altitude Research Stations Jungfraujoch, Bern, Switzerland (http://cosray.unibe.ch/). OTHER is a place holder for additional, as of yet unforeseen corrections. CORR is the probe count rate corrected for the above scaling factors CORR = FAST * PROBE * PRESS / SCALE * SANPE / INTEN This count is used to estimate soil moisture at the probe site. ERR is the uncertainty associated with the corrected probe count, based on poissonian statistics (sqrt(N)) or original count rate. ------------------------------------------------------------------------------ LEVEL 3 Level 3 data takes quality controlled, corrected Level 2 data and converts it directly to a soil moisture measurement. Example Level 3 data is as follows: YYYY-MM-DD HH:MM SOILM DEP SM12H D12 2011-03-21 17:52 36.6 12 29.1 14 Where YYYY-MM-DD is the end date (UTC) of the neutron count interval, when the neutron data are forwarded to the server and neutron count reset. HH:MM is the end time (UTC) of the neutron count interval, when the neutron data are forwarded to the server and neutron count reset. SOILM is the estimated soil moisture (% Volumetric) DEP is the estimated effective measurement depth (cm) SM12H is the soil moisture filtered using a 12 hr robust boxcar filter D12 is the measurement depth filtered using a 12 hr robust boxcar filter