Data from: Bioclimatic and physical characterization of the world's islands

The Earth’s islands harbor a distinct, yet highly threatened biological
and cultural diversity that has been shaped by geographic isolation and
unique environments. Island systems are key natural laboratories for
testing theory in ecology and evolution. However, despite their potential
usefulness for research, a quantitative description of island environments
and an environmental classification are still lacking. Here, we prepare a
standardized dataset and perform a comprehensive global environmental
island characterization for 17,883 of the world’s marine islands >1
km² (∼98% of total island area). We consider area, temperature,
precipitation, seasonality in temperature and precipitation, past climate
change velocity, elevation, isolation, and past connectivity – key island
characteristics and drivers of ecosystem processes. We find that islands
are significantly cooler, wetter and less seasonal than mainlands.
Constrained by their limited area, they show less elevational
heterogeneity. Wet temperate climates are more prevalent on islands,
whereas desert climates are comparatively rare. We use ordination and
clustering to characterize islands in multidimensional environmental space
and to delimit island ecoregions which provides unique insights into the
environmental configuration and diversity of the world’s islands.
Combining ordination and classification together with global environmental
data in a common framework opens up avenues for a more integrative use of
islands in biogeography, macroecology, and conservation. To showcase
possible applications of the presented data, we predict vascular plant
species richness for all 17,883 islands based on statistically derived
environment-richness relationships.