ACCLIMATE Water Table Depth Data
2026-04-28
CiPEHR Graphs
This figure shows the distribution of depth from the ground surface to the water table in Control and Soil Warming plots in CiPEHR during the growing season. The x-axis shows the month the measurements were taken and the y-axis shows the depth to the water table (in cm). The boxplots display the spread of the data for each month from 2009 to 2025. The red dots show how the year 2025 compares to the previous years, highlighting the monthly values for that year in relation to the overall distribution.
This figure shows the average depth from the ground surface to the water table in Control and Soil Warming plots in CiPEHR. The x-axis shows the year the measurements were taken and the y-axis shows the average depth to the water table (in cm).
Gradient Graphs
This figure shows the distribution of depth from the ground surface to the water table in Extensive, Moderate, and Minimal sites in Gradient during the growing season. The x-axis shows the month the measurements were taken and the y-axis shows the depth to the water table (in cm). The boxplots display the spread of the data for each month from 2009 to 2025. The red dots show how the year 2025 compares to the previous years, highlighting the monthly values for that year in relation to the overall distribution.
This figure shows the average depth from the ground surface to the water table in Extensive, Moderate, and Minimal sites in Gradient The x-axis shows the year the measurements were taken and the y-axis shows the average depth to the water table (in cm).
Summary Points
- What is it: Water table depth is a measurement of the distance between the ground surface and the water table (i.e., the upper layer of the soil that is saturated with groundwater).
- Non-Scientific name: Depth to groundwater
- Why do we measure it: We measure water table depth as a metric of soil saturation and groundwater availability. Changes in the water table depth can be a signal for permafrost thaw, and changing hydrology.
- How was it measured: Perforated PVC pipes are inserted into the ground that reach the water table. We can measure the distance from the surface of the ground to the surface of the water table by putting a meter stick into the PVC pipe and recording the distance. A greater positive value indicates that the water table is further away from the ground surface (0 cm). A negative value indicates the area is flooded, and the water table is sitting above the ground surface.
- Long term trends:
- CiPEHR:
- Long-term: The water table has been getting closer to the ground surface in the Soil Warming treatment since the start of the experimental warming. The water table stays relatively at the same depth from the ground surface in the Control treatment. The water table in the Soil Warming treatment is closer to the ground surface than in the Control treatment.
- In 2025: [UPDATES NEEDED] The water table depth got closer to the ground surface in both Soil warming and Control plots as the growing season progressed, with the water table the furthest away from the ground surface in June and the water table closest to the ground surface in September. The water table in the Soil Warming treatment is always closer to the ground surface compared to the Control treatment, regardless of month.
- Gradient:
- Long-term: The depth to the water table between each site at Gradient was relatively the same, except in the past 6 years, the water table is closer to the ground surface in Minimal compared to Extensive and Moderate.
- In 2025: NEED TO UPDATE
- Where is this science going?:Ground saturation can determine where different types of decomposition occur. Aerobic decomposition occurs in dry soil layers where microbes break down organic matter and release it as carbon dioxide into the atmosphere. Anaerobic decomposition occurs in waterlogged soil layers where microbes break down organic matter and release it as methane. We need to better understand how changing hydrology and soil saturation affect the magnitude and form of carbon released into the atmosphere.
Images
Ariella Thompson inserts a meter stick into a perforated PVC pipe at one of the plots in Healy, Alaska at the ACCLIMATE site to measure water table depth.