Weekly, monthly and yearly recreation demand maps for the UK

Predicted recreation demand was expressed as the total number of projected visits for local recreation in target cells. To estimate the total number of projected visits in each 250 m target cell, a bespoke version of the universal law of human mobility was used (Schläpfer et al., 2021), as seen in the function below:

Demand_i = Attractiveness_i × ∑ |j=1 to j= all| [(Population_j) / ((Frequency_ij × Traveling distance_ij)^∝)]

with i the target cell, j the source cell and the scaling factor α = 2.17, following Schläpfer et al. (2021); frequency is expressed as number of visits per year; travelling distance in kilometres.

The distance decay gravity function considers the number of visits to single target cells (i) depending on the "Population" size in a source cell (j), corrected by the "Traveling distance" from that source cell to the target cell and the "Attractiveness" of the target cell – the assumed relative likelihood of visiting that target cell. Traveling distance was estimated non-Euclidean, as a cost-weighted distance using the UK road network in 2.5 km cells and the distance to the nearest road within cells. The number of visits per year from the source cell to the target cell, i.e. the Frequency, is also included (weekly, monthly and yearly), since people tend to visit more often where there is a shorter distance to travel. Thus, for a given distance more predicted visits will arise from more densely populated cells compared with less populated cells, whereas at shorter distances more visits are predicted than at longer distances for a given source population density. For each target cell, the equation is summed over all potential source cells. See documentation accompanying the data for a detailed description of the data used for each parameter in the equation.