1. Short Description of the Sensor Temperature/humidity data logger Onset HOBO U23-001. Weatherproof data logger with built-in temperature and relative humidity sensors. The Relative Humidity sensor provides superior durability in humid environments and is user-replaceable. All the loggers were mounted in Onset RS1 radiation shields. 1.2 Specification Temperature Sensor Operation range internal sensors: -40° to 70°C (-40° to 158°F) U23-002 external temperature sensor: -40° to 70°C (-40° to 158°F) U23-003 and U23-004 external sensors: -40° to 100°C (-40° to 212°F), with tip and cable immersion in fresh water up to 50°C (122°F) for one year Accuracy: ±0.21°C from 0° to 50°C (±0.38°F from 32° to 122°F) Resolution: 0.02°C at 25°C (0.04°F at 77°F); see Plot A in the manual Response Time (typical to 90%) U23-001 internal sensor: 40 minutes in air moving 1 m/sec U23-002 external temperature sensor: 5 minutes in air moving 1 m/sec U23-003 and U23-004 external sensors: 3 minutes in air moving 1 m/sec; 30 seconds in stirred water Stability (drift): < 0.1°C (0.18°F) per year Relative Humidity Sensor (U23-001, U23-002 only) Operation range: 0-100% RH, -40° to 70°C (-40° to 158°F) Exposure to conditions below -20°C (-4°F) or above 95% RH may temporarily increase the maximum RH sensor error by an additional 1% Accuracy: ±2.5% from 10% to 90% RH (typical), to a maximum of ±3.5% including hysteresis at 25°C (77°F); below 10% and above 90% ±5% typical Resolution: 0.05% Response Time (typical to 90%) U23-001: 40 minute in air moving 1 m/sec with protective cap U23-002: 5 minutes in air moving 1 m/sec with protective cap Stability (drift): < 1% per year typical Logger Operation range: -40° to 70°C (-40° to 158°F) Real-time clock: ± 1 minute per month 0° to 50°C (32° to 122°F) Battery: 1/2 AA, 3.6 Volt lithium, user-replaceable (part # HP-B) Battery life (typical use): 3 years with 1 minute or greater logging interval Memory (non-volatile): 64K bytes memory (approx. 21,000 temperature and RH measurements) 2. Measurement Strategy during the Campaign Six sensors were deployed within the forest canopy and anchored to trees at about 2 meters above the ground. The sensors were located along the eastern slope of Monte Baldo at different altitudes, spanning from 1169 m to 1640 m. The choice to place the instruments within the forest canopy was driven by two reasons: first, we aimed to monitor near-surface temperature and humidity variation with height, avoiding as much as possible the influence of solar radiation; second, we wanted to monitor the conditions within the forest canopy surrounding the slope. 2.1 Description of data collection Data were collected at the end of the campaign, following a cross-calibration check. 2.2 Time period covered by the data The sensors were deployed on 19 June 2025 and uninstalled on 9 October 2025. After this period the sensors were cross-calibrated by leaving them close together in a room until the 13th of October. The data logging was regular during the deployment period and no data gaps have been observed. The sampling period was set at 10 minutes. 2.3 Time zone UTC+1 2.3 Physical location Number LAT LON Altitude Name Code 1 45.65730662 10.83103226 1120 IME 10976861 2 45.66443408 10.82602044 1241 BEND 10976865 3 45.6642579 10.82298578 1327 VALFREDDA 10976857 4 45.66854545 10.82021503 1405 PATH 1 10976866 5 45.66827327 10.81726206 1518 PATH 2 10976860 6 45.66797125 10.81575222 1592 PATH 3 10976863 3. Data Processing Data was transformed from .csv to .nc format. No other data processing was carried out. 3.1 Description of derived parameters and processing techniques used None 3.2 Description of quality assurance and control procedures None 4. Data Format NetCDF 4.1 Data file structure The file contains the observations collected by the 6 dataloggers throughout the campaign. The dataset contains the observations of temperature, relative humidity, and dewpoint for the six dataloggers following the numeration of the instruments reported in section 2.3, Physical location. The physical location and the code of the HOBOs are also reported in the “long_name” tag of each variable. "Temp_1":{ "units": "C", "long_name":"Air Temperature at 1120 m a.s.l - HOBO 1 - Malga IME [45.65730662, 10.83103226]", "height": 2, "instrument": ID 10976861"}, "Temp_2":{ "units": "C", "long_name":"Air Temperature at 1241 m a.s.l - HOBO 2 - BEND [45.66443408, 10.82602044]", "height": 2, "instrument": ID 10976865"}, "Temp_3":{ "units": "C", "long_name":"Air Temperature at 1327 m a.s.l - HOBO 3 - Malga Val Fredda [45.6642579, 10.82298578]", "height": 2, "instrument": ID 10976857"}, "Temp_4":{ "units": "C", "long_name": "Air Temperature at 1405 m a.s.l - HOBO 4 - PATH 1 [45.66854545, 10.82021503]", "height": 2, "instrument": ID 10976866"}, "Temp_5":{ "units": "C", "long_name":"Air Temperature at 1518 m a.s.l - HOBO 5 - PATH 2 [45.66827327, 10.81726206]", "height": 2, "instrument": ID 10976860"}, "Temp_6":{ "units": "C", "long_name":"Air Temperature at 1592 m a.s.l - HOBO 6 - PATH 3 [45.66797125, 10.81575222]", "height": 2, "instrument": ID 10976863"}, "RH_1":{ "units": "%", "long_name":"Relative Humidity at 1120 m a.s.l - HOBO 1 - Malga IME [45.65730662, 10.83103226]", "height": 2, "instrument": ID 10976861"}, "RH_2":{ "units": "%", "long_name":"Relative Humidity at 1241 m a.s.l - HOBO 2 - BEND [45.66443408, 10.82602044]", "height": 2, "instrument": ID 10976865"}, "RH_3":{ "units": "%", "long_name":"Relative Humidity at 1327 m a.s.l - HOBO 3 - Malga Val Fredda [45.6642579, 10.82298578]", "height": 2, "instrument": ID 10976857"}, "RH_4":{ "units": "%", "long_name": "Relative Humidity at 1405 m a.s.l - HOBO 4 - PATH 1 [45.66854545, 10.82021503]", "height": 2, "instrument": ID 10976866"}, "RH_5":{ "units": "%", "long_name":"Relative Humidity at 1518 m a.s.l - HOBO 5 - PATH 2 [45.66827327, 10.81726206]", "height": 2, "instrument": ID 10976860"}, "RH_6":{ "units": "%", "long_name":"Relative Humidity at 1592 m a.s.l - HOBO 6 - PATH 3 [45.66797125, 10.81575222]", "height": 2, "instrument": ID 10976863"}, "DewPt_1":{ "units": "%", "long_name":"Dew Point at 1120 m a.s.l - HOBO 1 - Malga IME [45.65730662, 10.83103226]", "height": 2, "instrument": ID 10976861"}, "DewPt_2":{ "units": "%", "long_name":"Dew Point at 1241 m a.s.l - HOBO 2 - BEND [45.66443408, 10.82602044]", "height": 2, "instrument": ID 10976865"}, "DewPt_3":{ "units": "%", "long_name":"Dew Point at 1327 m a.s.l - HOBO 3 - Malga Val Fredda [45.6642579, 10.82298578]", "height": 2, "instrument": ID 10976857"}, "DewPt_4":{ "units": "%", "long_name": "Dew Point at 1405 m a.s.l - HOBO 4 - PATH 1 [45.66854545, 10.82021503]", "height": 2, "instrument": ID 10976866"}, "DewPt_5":{ "units": "%", "long_name":"Dew Point at 1518 m a.s.l - HOBO 5 - PATH 2 [45.66827327, 10.81726206]", "height": 2, "instrument": ID 10976860"}, "DewPt_6":{ "units": "%", "long_name":"Dew Point at 1592 m a.s.l - HOBO 6 - PATH 3 [45.66797125, 10.81575222]", "height": 2, "instrument": ID 10976863"} } 5. Data Remarks The installation of the sensors lasted a few hours on 19 June 2025. Use data starting from 20 June 2025. 5.1 Known missing data periods None 5.2 Software compatibility Any software that can read NetCDF files.