We release three data products for monthly groundwater storage (GWS) changes in North America. In the first one, we provide an independent estimate for monthly GWS changes within North America in 1-degree-grids and their trends. In the second one, we give the monthly GWS changes and the trends averaged for the 5 major GWS trend anomalies in around Saskatchewan, Nevada, California, Arizona and Texas, respectively. The third data product includes the monthly GWS changes and the trends averaged for the 14 states or provinces in the US and Canada, affected by the above GWS trend anomalies, i.e., for Saskatchewan, Montana, Nevada, California, Arizona, New Mexico, Texas, Oklahoma, Kansas, Alberta, North Dakota, Minnesota, Colorado and Chihuahuas, respectively. Our estimates of monthly GWS changes and their trends can serve as alternative and beneficial input for sustainable management of groundwater resources in North America. Our data products are derived from the release-6 version of GRACE monthly level-2 data, GNSS data, two land surface models of GLDAS 2.1 for soil moisture and snow water equivalent, and satellite altimetric lake level data. Unlike previous studies, glacial isostatic adjustment (GIA) effects are eliminated by employing an independent separation approach with the aid of GNSS vertical velocity data (Wang et al., 2013). The monthly changes of those GWS anomalies are validated by well level data. The monthly GWS changes for the 14 states or provinces are basically to show compatible variations with precipitation drought intensity level variations. We find a GWS increasing trend anomaly in Saskatchewan and 4 GWS declining trend anomalies with peaks in Nevada, California, Arizona and Texas, respectively. As they are not estimated using GIA models in the correction and their comparison with available well level and drought data confirms their reliability, we suggest our data products as alternative input to groundwater resource management in the discussed areas.

File naming and required software

We release three corresponding data products:

1) 162 months of groundwater storage changes (GWS) changes in 1584 1-degree cells for the whole North American continent. Data can be found in equivalent water thickness (EWT) in file ‘gws_NA_deg1grid.txt’ with corresponding uncertainties listed in file ‘gws_sigma_ NA_deg1grid.txt’. Format for each data line is longitude and latitude of the cell center followed by the trend rate in mm/yr. The next 162 columns are GWS in mm EWT for all month with GRACE data from April 2002 to June 2017.

2) 162 months of EWT GWS changes and their uncertainties averaged for the 5 major GWS trend anomalies identified in North America. Data are listed in file ‘Monthly_GWS_changes_for_5_trend_anomalies.txt’. Format for each data line is time in yr, GWS change in Gt, uncertainty in Gt, GWS change in mm EWT, uncertainty in mm for Saskatchewan, Nevada, California, Arizona and Texas, respectively.

3) 162 months of EWT GWS changes and their uncertainties averaged for the 14 states or provinces in the US and Canada that are affected by the 5 major GWS anomalies. Data are listed in file ‘Monthly_GWS_changes_for_14_states_or_provinces.txt’. Each data line includes time in yr, GWS change in Gt, uncertainty in Gt, GWS change in mm EWT, uncertainty in mm for Saskatchewan, Montana, Nevada, California, Arizona, New Mexico, Texas, Oklahoma, Kansas, Alberta, North Dakota, Minnesota, Colorado and Chihuahuas, respectively.

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Cite as:

Wang, H., Xiang, L., Steffen, H., Wu, P., Jiang, L., Shen, Q., Li, Z., Hayashi, M. (2021). North America groundwater variation data products (2002 to 2017). A Big Earth Data Platform for Three Poles, DOI: 10.11888/Hydro.tpdc.271654. CSTR: 18406.11.Hydro.tpdc.271654. (Download the reference： RIS | Bibtex )

Related Literatures:

1. Wang, H., Xiang, L., Steffen, H., Wu, P., Jiang, L., Shen, Q., Li, Z., & Hayashi, M. (2021). GRACE-based estimates of groundwater variations over North America from 2002 to 2017, Geodesy and Geodynamics, in revision.( View Details | Bibtex)

2. Wang, H., Jia, L., Steffen, H., Wu, P., Jiang, L., Hsu, H., Xiang, L., Wang, Z., & Hu, B. (2013). Increased Water storage in North America and Scandinavia from GRACE gravity data, Nature Geoscience, 6(1), 38-42, doi:10.1038/ngeo1652.( View Details | Bibtex)

Using this data, the data citation is required to be referenced and the related literatures are suggested to be cited.

Support Program

National Natural Science Foundation of China (No:41974009)

Alberta Innovates (the Groundwater Recharge in the Prairies project)

National Natural Science Foundation of China (42004007) (No:42004007)

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