Surface boundary layer turbulence on an 11% slope.

<p>Surface Boundary layer turbulence during mesoscale slope flows on a north-facing 11% slope off the Missouri Flats descending to the Yakima River in Eastern Washington State, USA. Measurements were made in support of a micrometeorological gas exchange research project during the months of March, May, June, August, and September over 2 years (2008-2009).</p>

<p>Meteorological measurement records (WA_Met_2008-2009.csv) consist of valid ½ hourly averages of air temperature, relative humidity, barometric pressure, surface wetness, solar radiation, and wind speed, wind direction, Monin Obukov length, friction velocity, roughness length, dissipation rate, characteristic temperature, as well as turbulence stationarity and homogeneity statistics for the sonic anemometer measurements:  </p>

<ul>
<li>Air temperature and humidity measurements made using Vasiala HMP45C hygrothermometer at</li>
<li>Barometric pressure measurements made using Setra 278 aneroid barometer</li>
<li>Surface wetness measurements made using VAC resistance grid</li>
<li>Solar radiation measurements made using LiCOR 190SB silicon pyranometer</li>
<li>Wind and turbulence measurements were made using RM Young 91000 3 dimensional sonic anemometers sampling the wind at 16Hz at 2.5 m (sonic 1), 4 m (sonic 2) and 17 m (sonic 3) above ground level.</li>
</ul>

<p>Turbulence measurement records consist of turbulence statistics (variances and covariances of 3 orthogonal wind components and sonic temperature) at 100s intervals.  Turbulence statistics are provided for (1) valid data, (2) invalid data due to spike values (greater than 3 standard deviations of the 100s mean), and (3) invalid data due to more than 10% of the measurements in the 100s period missing due to optical path obstruction. 3 files, one for each sonic anemometer are provided:</p>

<ul>
<li>Sonic 1 measurements: WA_Slope_son1_2008-2009.csv</li>
<li>Sonic 2 measurements: WA_Slope_son2_2008-2009.csv</li>
<li>Sonic 3 measurements: WA_Slope_son3_2008-2009.csv</li>
</ul>

<p>NOTE: Temporal gaps in measurements exist due to instrument and communications failures as well as gaps due to no experimental need for the measurements.  Note that missing measurement periods do not have Date/Time record placeholders in the dataset.</p>

<p>Additional files included:</p>

<p>The sonic anemometer Standard Operating Procedure for the measurements is included: "SOP Ultrasonic Anemometer (Revision 1.0) 2-20-08.pdf'"</p>

<p>The Data Dictionary for the ½ hourly meteorological measurements is 'SlopeMet_Data Dictionary.pdf'</p>

<p>The Data Dictionary for the 100s turbulence measurements is 'SlopeTurb_Data Dictionary.pdf'</p>