Bloomfield, J.P.; Marchant, B.P.; Wang, L.

Historic Standardised Groundwater level Index (SGI) for 54 UK boreholes (1891-2015)

Monthly Standardised Groundwater level Index (SGI) for observation boreholes across the UK from 1891 to 2015, based on reconstructed groundwater level time series (Bloomfield et al., 2018; https://doi.org/10.5285/ccfded8f-c8dc-4a24-8338-5af94dbfcc16). Standardised groundwater levels have been estimated using a non-parametric normal scores transform of groundwater level data for each calendar month. Probability estimates of an SGI being less than 0, -1, -1.5 and -2 are also provided.

Publication date: 2018-03-12

Get the data

Format of the dataset : Comma-separated values (CSV)

Access and use conditions

This resource is embargoed and will be made available by 1 January 2019 at the latest  

This resource will be available under the terms of the Open Government Licence

You must cite: Bloomfield, J.P.; Marchant, B.P.; Wang, L. (2018). Historic Standardised Groundwater level Index (SGI) for 54 UK boreholes (1891-2015) . NERC Environmental Information Data Centre. https://doi.org/10.5285/d92c91ec-2f96-4ab2-8549-37d520dbd5fc

 

This dataset is part of the following

Where/When

Study area
Temporal extent
1891-01-01    to    2015-12-31

Provenance & quality

Monthly standardised groundwater levels have been estimated using a non-parametric normal scores transform for the data for each calendar month. The normal scores transform assigns a value to observations, in this case monthly reconstructed groundwater levels (Bloomfield et al., 2018; https://doi.org/10.5285/ccfded8f-c8dc-4a24-8338-5af94dbfcc16), based on their rank within a data set, in this case groundwater levels for a given month from a given hydrograph. The normal scores transform is undertaken by applying the inverse normal cumulative distribution function to n equally spaced pi values ranging from 1/(2 n) to 1 − 1/(2 n). The values that result are the SGI values.

The quantification of uncertainty in the reconstructed groundwater levels for a given site is based on the Generalised Likelihood Uncertainty Estimation (GLUE) methodology. Parameter sets are considered to be behavioural if their Nash Sutcliffe Efficiency score exceeds 0.5. For each site, all of the behavioural groundwater level reconstructions are converted to SGI series. The probability of the SGI being within an interval on a particular date is equal to the proportion of these behavioural SGI series that fall within this interval and the probability of SGI being less than 0, -1, -1.5 and -2 is reported.

Correspondence/contact details

John Bloomfield
British Geological Survey
Maclean Building, Benson Lane, Crowmarsh Gifford
Wallingford
Oxfordshire
OX10 8BB
United Kingdom
enquiries@bgs.ac.uk

Authors

Bloomfield, J.P.
British Geological Survey
Marchant, B.P.
British Geological Survey
Wang, L.
British Geological Survey

Other contacts

Custodian
Environmental Information Data Centre
Publisher
NERC Environmental Information Data Centre

Spatial

Spatial representation type
Tabular (text)
Spatial reference system
OSGB 1936 / British National Grid

Tags

Topic categories
Environment , Geoscientific Information , Inland Waters
INSPIRE Theme
Geology
Hydrography
Keywords
Borehole,  Drought catalogue,  Drought indicator,  Drought inventory,  Droughts,  Historic Droughts,  SGI,  Standardised Groundwater level Index,  United Kingdom Water scarcity