Description

The Innsbruck Box (i-Box) is a testbed for studying boundary layer processes in highly complex terrain. Designed to be a long-term "reference box" for studying the characteristics of turbulence structure and exchange processes in truly complex topography, i-Box represents an integrated approach combining three-dimensional long-term turbulence observations with high-resolution numerical modeling. The i-Box observational stations are located in the Inn Valley, an approximately northeast-southwest oriented valley in western Austria, characterized by very complex terrain with steep slopes, flat foothills, numerous side valleys, and variable land use characteristics. The locations of the core sites (six turbulence stations) were chosen to represent different topographic features in order to secure the universality of the obtained results. Further information about the i-Box project can be found in Rotach et al. (2017) and on the i-Box WIKI.

The mountain-top station CS-MT21 is located on Arbeserkogel, slightly below ridgetop on a steep west-facing slope. The 4-m high tower is a full energy-balance station and is instrumented with a sonic anemometer and a Krypton hygrometer at 4.7 m, as well as additional wind, temperature and humidity sensors at multiple levels.

Site characteristics

Coordinates: 47.320654˚N, 11.746592˚E (UTM: 707552.34E, 5244456.79 N)

Altitude: 2015 m MSL

Slope angle: 21˚

Slope orientation: 274˚

Surface characteristics: high-alpine vegetation

Status: operational since September 2014

Power supply: solar panel, fuel cell

Datalogger: CR3000

History/logbook: logbook and data availability

Instrumentation

Instrument	Height	Serial number	Notes
Turbulence
METEK uSonic3	4.7 m	0105123843	Angle to true north: 6˚
Campbell KH20	4.7 m	1735	until 2 June 2017 Path length: 0.01254 Path separation: 0.3551 xkw: -0.189 ln(mV)m3/g Intercept: 3946 mV since 2 June 2017 Path length: 0.0124 Path separation: 0.3551 xkw: -0.187 ln(mV)m3/g Intercept: 3508 mV Path separation:
Temperature/Humidity
Rotronic HC2-S3 "1m"	0.48 m
Rotronic HC2-S3 "2m"	1.90 m		dismounted
Rotronic HC2-S3 "3m"	3.95 m	20467243
Wind
Cup anemometer	0.55 m		dismounted 2021-09-18
Cup anemometer	1.90 m
Cup anemometer	3.95 m
Young wind monitor	2.00 m
Pressure
Setra 278		5320479	in logger box
Precipitation/Snow
SR50A		4899
Radiation
CNR4	0.90 m	110706	SWd: 15.25 uV/Wm2 SWu: 13.80 uV/Wm2 LWd: 14.89 uV/Wm2 LWu: 13.48 uV/Wm2
Soil
Heat Flux Plate HFP01	10 cm	004332	63.9 uV/Wm2
Campbell 107 Temp probe	5 cm
Campbell 107 Temp probe

Datasets

RAWDATA

Uncorrected 1-min raw data, no quality checks applied

RADIAT1

1-min radiation data after applying the respective calibration coefficients to the uncorrected raw data; no quality checks applied

FLUXL1

Processed turbulence data with an averaging interval of 30 min (processing was performed using EdiRe)

Processing includes despiking; double-rotation of the wind components; detrending with a recursive filter and a time constant of 200 s; and applying frequency-response corrections, heat-flux corrections for humidity effects, oxygen corrections for KH20, and WPL corrections. The datafile contains several quality flags.

QC RAW

for creation rules see picture: Rule_QC_RAW

QC RADIAT1

for creation rules see picture: Rule_QC_RAD1