Daily weather summaries from Toolik Field Station Meteorological Station, Toolik Lake, Alaska. Included are daily averages and/or maximums and minimums of air, soil and lake temperature, wind speed, vapor pressure, and sum of global radiation and precipitation recorded near Toolik Lake.
Data set ID:
EML revision ID:
EXPERIMENTAL DESIGN AND METHODS: Weather data at Toolik Lake has been collected by the Arctic LTER since June 1988. The station is located about 50 meters south of the lake's edge in a sedge/moss (Tomenthypnum nitens-Carex bigelowii) vegetation. Sensors that are measured every minute and averaged or totaled every hour include: air temperature and relative humidity at 1 and 5 meters, wind speed at 1 and 5 meters, wind direction at 5 meters, global solar radiation, photosynthetically active radiation, barometric pressure, and precipitation. Sensors measured every 10 minutes and averaged every three hours include: soil temperatures, lake temperature, lake depth, and evaporation pan depth and pan water temperature. Pan evaporation are only measured during the summer months. The hourly data are in the file yyyyDLTLH.DAT, the three hourly data are in yyyyDLTLO.DAT, and daily summaries are in yyyyDLTLD.DAT.
A second datalogger, Toolik Moist Acidic Tussock station, about 700 meters from the main weather station logs air and soil temperatures and photosynthetically active radiation in the experimental treatment plots. Treatments include greenhouse, shading, and fertilization. In the control plot wind speed and direction, global solar radiation and unfrozen precipitation are also measured. This station is also used as a backup to the main weather station.
The Imnavait weather station, 12 kilometers away and 200 meters higher, is also used to fill in data gaps. Regressions of summer air temperature between Imnavait and with Toolik are good but during the winter months there is greater variability. This station is maintained by Larry Hinzman and Doug Kane, Water Research Center; University of Alaska Fairbanks; Fairbanks, AK 99775-5860. Precipitation data from the Natural Resources Conservation Service (NRCS) Alaska Imnavait weather station is also used to fill in the data gaps. Please contact Rick McClure, Data Collection Officer, Natural Resources Conservation Service, 949 E. 36th Ave., Suite 400,, Anchorage, AK 99508-4362, (907) 271-2424 for more details.
The full description of the sensors and site is in file SENSORS.DOC. The original data is in file yyyyDLTDAT.ZIP which is archived at The Marine Biological Lab, Woods Hole, MA.
NOTES AND COMMENTS: Wind speed less than .447 is considered calm.
Radiation data were not totaled for the winter months since no attempt was made to keep sensors snow and frost-free. Lake temperature is measured at the lake depth sensor. Therefore the lake depth measurements give the depth at which lake temperature is measured. See additional notes under Comments variable.
On August 19-20, 2008 - the weather station underwent an upgrade to the main datalogger: CR3000. Wind speed at 1 m was removed. Wind speed at 5m was replaced w/ calibrated sensor. Pyranometer was replaced w/ Kipp and Zonen CMP6 (ventilation unit - year round numbers are now available). Temperature/RH at 1 m was removed and replaced w/ an RMYoung T/RH probe at 3 m.
Wind speed data from Jan 1, 2009-April 19, 2009 is suspect.
Winter precipitation (precip when temp < approx 1 C) is always suspect. False precipitation events are common in winter.
5 minute data are missing from Jan 1-April 19, 2009.
Changes relative to form from past years: 'Rain' changed to 'precipitation' and the gauge reported is only the Pluvio one. 'AT' variable changed to 'ATAVG' to reflect accuracy. 'WSMin' Added. 'Wind SP 5m' changed to 'WSAVG' for consistency. Data missing from 4/14 through 4/19 during logger change out. Some parameters changed with new logger (see methods). Data processed on a MacBook Pro running OS 10.5.8 and MSOffice 2008.
Changes to past form denoted below in comments section.
Version 2: Corrected Distrubution URL. It had xlsfiles in the path. Jim L 19Jun14
Version 3: Changed Distrubution URL since the LTER network DAS system is being discontinued. JimL 9Apr2015
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