Location of Sampling Stations: For the APT Experiment Map, please check APT map

Headquarters weather station (grid C-16): Ott Pluvio². Headquarters 2 (C-16)   
Prairie rain gauges: Belfort Weighing Rain gauges: 020A (C-30); 002C (M-31); N04D (J-27)-upland; 020B (O-28); K04B (T-23); 004B (G-26); N01B (P-23); N02B (H-22); N04D (L-23)-lowland.

HOBO Data Logging Rain Gauges: R01A (C-30); 002C (M-31); N04D (J-27)-upland; 020B (O-28); K01B (T-23); 004B (G-26); N01B (P-23); N04D (L-23)-lowland.

Frequency of Sampling: Continuous sampling at headquarters weather station. Continuous from April 1 to October 31 for rain gauges on prairie.

Variable Measured: Daily amounts of precipitation (mm).

Methods: Precipitation is measured at headquarters by an Ott Pluvio² rain gauge (continuous remotely monitored). It was installed in March 2010 at the Konza HQ site. Data is collected and processed by a Campbell Scientific (CR800) data logger and downloaded via wireless internet every 15 minutes.
Prior to the Pluvio, Belfort weighing rain gauges, one with a seven-day clock HQ1 and one with a 24-hour clock HQ2 (equipped with a wind screen) were used to record HQ precipitation. Additionally, nine other Belfort weighing rain gauges are installed on the Konza Prairie. Gauges in R01A, 004B, N02B, N04D (upland and lowland), K04B, and N01B have 24-hour clocks for finer resolution of storm events. Gauges in 020A and 002C have seven-day clocks. The prairie rain gauges are not operated during the winter months (November-March).

HOBO Data Logging Rain Gauges (RG3-M) were installed in April 2022 (004B, N04d-upland, 002C, N01B, and N04D-lowland) and April 2023 (R01A(formerly 020A), 020B, and K01B (formerly K04B).  Both Belforts and HOBOs will run concurrently for the remaining life of the Belfort RGs. Collect data manually using a computer and 'HOBOware' USB base station. Check biweekly.

Routine Maintenance:
Charts on all Belfort weighing rain gauges require changing each week. Catch buckets in the rain gauges are emptied at the time of chart changing except when the headquarters rain gauge is winterized with antifreeze (see Belfort manual for details). Clock mechanisms require rewinding each week and pens must be refilled with ink.  The prairie rain gauges are sealed with plastic in the winter. Following significant precipitation events, the level of the antifreeze/water mixture in the buckets should be checked to avoid overflow. The antifreeze/water system should be discarded and refilled if dilution of the antifreeze past levels of protection occurs. Strip charts are read and hand entered into APT012.

The Ott Pluvio2 rain gauge processing program sends an e-mail to the weather station technician when the bucket is 3” below capacity and needs to be emptied. In the fall, antifreeze is added to the collection bucket, see Ott Pluvio2 manual for details. SAS formats data and generates daily date and 15-minute data from the Ott Pluvio2 rain gauge.

Data is downloaded from the HOBO units every 1-2 weeks.  They will follow the same operation schedule of April 1 to Oct 31 as the Belfort RGs.  The HOBOs will be calibrated every year before they are deployed in the spring.

Note: Missing data are signified with the ‘.’, and all data missing for the station of 4b, 2c, n4du, n2b in 2022.

Summary of All Changes:
1982: only operated one ‘HQ’ rain gauge
4/1/1983: added 20B, 2C, 4B
4/1/1983 – 4/1/1986: operating four rain gauges (HQ, 20B, 2C, 4B)
4/2/1986: added K01B, N01B, N02B, N4DF, N4DU, R01A (total of 10 rain gauges
8/20/1986: added HQ2 (total of 11 rain gauges)
3/19/2010: use new rain gauge ‘Ott Pluvio2.’ We have the new measures from this new rain gauge. For the period of ‘2010-01-06’ – ‘2011-03-28’ added comments ‘old rain gauge’ in the comment column
3/29/2011: shut off the ‘HQ2’ and old ‘HQ’ rain gauge (current: total of 10 rain gauges – 020B, 002C, 004B, HQ, K01B, N01B, N02B, N4DF, N4DU, R01A)
6/3/2018: converted apt011 data structure to long format, then merged with apt012 data; cleaned up blank cells, updated old rain gauge code to the current rain gauge code (watershed code).
March 2020: all nine Belfort RGs calibrated.  Three units failed calibration and will not be opened this season; 004B, 002C, and N4D upland.
April 2021:  N02B Belfort stopped working after less than one month and can not be calibrated.  Functioning Belfort RGs remain at 020B, N01B, N04D-lowland, K01B, and R01A.  R01A is the only seven-day clock, all others are 24-hour clocks.  We are in looking into replacing all units.
April 2022: Five HOBO Data Logging Rain Gauges (RG3-M) were purchased and will operate concurrently with the Belfort RGs.  The new HOBOs represent 004B, N04D-upland, and 002C locations, which had no representation in 2021.  N01B and N04D-lowland also had HOBOs running alongside the still functioning Belfort RGs.
April 2023:  Three additional HOBO rain gauges purchased and have been placed at 020B, K01B, and R01A.  The N02B location will no longer be monitored.
Dec 2023: There are 8 HOBO RGs operating in 2023, opened 5 Belfort RGs for 2023 season.

For additional metadata information see: http://lter.konza.ksu.edu/sites/default/files/DC.pdf

For additional methods information see: http://lter.konza.ksu.edu/sites/default/files/MM.pdf