Hourly temperature and humidity data from the LTER Moist Non-acidic Tussock Experimental plots (MNT).


Hourly data from the Toolik Moist Non-acidic Tussock Experimental plots (MNT). In 1999 a Campbell CR10x data logger was installed in block 2 of the experimental plots. The plots are located on a hillside near Toolik Lake (68 38' N, 149 36'W). Sensors were placed in control and greenhouse sites. Soil temperature profiles are reported in another file (1999-present_MNTsoil).

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Published on EDI/LTER Data Portal


Hobbie, S., Laundre, J. A. 2021. Hourly temperature and humidity data from the LTER Moist Non-acidic Tussock Experimental plots (MNT). Environmental Data Initiative. http://dx.doi.org/10.6073/pasta/a48892da5bc9eab27b18d2364dea6998

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Tuesday, August 17, 1999 to Sunday, April 18, 2021

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A Campbell CR10x data logger, in the LTER Toolik Moist Non-acidic Tussock Experimental plots (block 2), is used to monitor weather and soil temperatures.
Sensors in the control and greenhouse plots include: air temperature and relative humidity. These sensors are read every minute and averaged or totaled every hour.
Two profiles of soil temperature are measured per treatment plot with copper/constantan thermocouple wires (TC) installed at depths of 0,10, 20, and 40 cm in inter-tussock areas. The following label codes are used: CT = control, GH = greenhouses, NP = fertilized, GHF= greenhouse fertilized, plus a 1 or a 2 for the profile number. All soil sensors are read every 15 minutes and averaged every 3 hours.
Hourly, three hourly and daily summaries are in files yyDLMNTH.DAT, yyDLMNTO.DAT, and yyDLMNTD.DAT respectively, where yy is the year in which the data are collected. The original data are in file yyDLMNTDAT.ZIP which is archived at The Marine Biological Lab, Woods Hole, MA.

Variable Formula

VAPOR PRESS 3M: If Air Temp > 0 then (RH /100) * 6.1121 *exp(17.368 * AIR TEMP /(238.88 + AIR TEMP ))
If Air Temp < 0 then (RH /100) * 6.1121 *exp(17.966 * AIR TEMP /(238.88 + AIR TEMP )) (Buck 1981).
Reference Citations: Buck, A.L.. 1981 New equations for computing vapor pressure and enhancement factor. Journal of Applied Meteorology 20:1527-1532.

The covers on greenhouses are removed every fall and reinstalled every spring.
Missing values are indicated by #N/A.
Greenhouse air Temperature/RH sensor was not added until Jun15,2000.

May 2006 Battery wire corroded and logger lost power.
Attached battery but the program in the storage module had an error. The temp/rh instruction did not have a multiplier of 0.1 and offset of -40. Corrected the temperature in the spreadsheet but the RH was all at 100 since the program changes any value above 100 to 100.
13-Ju-l2006 Program corrected but the power wire for the Greenhouse probe was not connected.
27-Apr-2007 Downloaded the storage module. Wires were chewed and the logger had lost power. Reconnected the power multiplexer and Temp/RH. Could not get the Greenhouse Temperature /RH to work.
8-Jun-2008 Replaced GH temperature/RH sensor.
11-Jun-2009 Battery problems. Running only on solar panel so there is no data when sun is low .
24-Jul-2009 Sic Sic made a nest in the battery box and chewed lots of wires.
7-Aug-2009 Repaired wires for most sensor.
11-Aug-2009 Put GH temp/RH back on after repairing the wires.
13-Aug-2009 The GH temp/RH went out.

Version Changes: 

Version 3: 24Nov2015 Combined all the years into one file. Jim L
Version 5: Added data to April 18, 2021

Sites sampled.

Full Metadata and data files (either comma delimited (csv) or Excel) - Environmental Data Initiative repository.

Use of the data requires acceptance of the data use policy --> Arctic LTER Data Use Policy