Extended Data Fig. 1: Cumulative impact of human visitation across Antarctica.
From: Antarctica’s wilderness fails to capture continent’s biodiversity
a, Weighted relative impact (WRI) scores of the number of independent historical human visitation records per 25-km2 grid cell, weighted by the proportion of ice-free area in each cell and the eight adjacent cells. Visitation to sites with WRI scores ≤20 is likely to have had a negligible impact. Cells without WRI scores (grey) have no historical visitation record in the data set and are considered here as unvisited. b, WRI scores for the McMurdo Dry Valleys region. c, Location of 18 field camps (points) in the McMurdo Dry Valleys, used to validate the WRI scores (Extended Data Table 2). d, Frequency distribution of 1,999 bootstrapped binomial generalized linear model regression coefficients for the relationship between WRI scores and the presence/absence of field camps in the McMurdo Dry Valleys (b, c; n = 252 grid cells). The dashed line indicates the regression coefficient (0.0023) for the model fit to the original sample.
