Dissolved calcium and pH raster layers for freshwater environments in Canada and the USA

Calcium concentration and pH are key parameters that are linked to multiple chemical and biological processes in freshwater environments. This dataset presents high-resolution (10 x 10 km) interpolated raster layers for these two variables across Canada and the continental USA. These layers were generated via spatial interpolation (Kriging with a fixed zero nugget) after comparison of multiple interpolation methods, using water quality data for lakes and rivers compiled from multiple sources. This is the first time that such data have been made available at this scale and resolution, providing a valuable resource for research, including projects evaluating risks from environmental change, pollution, and invasive species. , For a detailed description of how the component data were assembled, processed, and used to generate interpolated rasters, please consult the associated publication., , # Dissolved calcium and pH raster layers for freshwater environments in Canada and the USA

[https://doi.org/10.5061/dryad.dv41ns24c](https://doi.org/10.5061/dryad.dv41ns24c)

## Description of the data and file structure

The dataset consists of interpolated rasters of freshwater calcium concentration (mg/L) and pH for Canada and the USA. Rasters are available both 'masked' using country outlines, and 'unmasked' to allow users to carry out various transformations or to use their own territory outlines if required. For each interpolated raster, an associated 'kriging variance' raster is provided to provide an indication of the uncertainty in the interpolated values. Data used for the interpolations are also provided; however, some data providers did not give permission for open sharing of their data so these records are not included in the shared files. Detailed metadata documents are provided for each of the database files.

#### Rasters

All rasters are provided in the North America ...