The effect of spatial resolution on projected responses to climate warming

• Published in: Diversity & distributions 2012-10, Vol.18 (10), p.990-1000
• Main Authors: Gillingham, P. K., Huntley, B., Kunin, W. E., Thomas, C. D.
• Format: Article
• Language: English
• Subjects: Animal, plant and microbial ecology; Applied ecology; Beetles; BIODIVERSITY RESEARCH; Biological and medical sciences; Carabus; Carabus glabratus; Climate change; Climate models; Climate science; Climatology. Bioclimatology. Climate change; Coleoptera; conservation; distribution models; Earth, ocean, space; Ecological modeling; Exact sciences and technology; External geophysics; extinction; Fundamental and applied biological sciences. Psychology; General aspects; Global warming; Habitat conservation; Insecta; Invertebrates; Meteorology; Microclimates; Modeling; Poecilus versicolor; Species; Surface temperature; Temperature distribution
• ISSN: 1366-9516; 1472-4642
• DOI: 10.1111/j.1472-4642.2012.00933.x

Aim: To determine how changing the resolution of modelled climate surfaces can affect estimates of the amount of thermally suitable habitat available to species under different levels of warming. Location: Lake Vyrnwy RSPB Reserve, which covers around 9700 hectares of a topographically diverse landscape in Wales. Methods: A recently published microclimate model was used to predict maximum, minimum and mean temperatures at 5 × 5 m resolution for the study site, under current and possible future conditions. These temperature surfaces were then averaged to produce coarser resolution surfaces, up to a maximum of 1 × 1 km resolution. Ground beetles were collected using pitfall traps between May and August 2008. Generalized linear models (GLMs) were fitted to the temperature surfaces to predict the amount of landscape suitable for a northerly-distributed ground beetle, Carabus glabratus, and the most southerly-distributed ground beetle found at the site, Poecilus versicolor, under current and possible future conditions. Results: A wider range of temperatures are expected within our site when temperature is modelled at finer resolutions. Fitting GLMs at different resolutions resulted in the inclusion of different temperature variables in the best models. Coarser resolution models tended to have higher prediction error, and different resolution models predicted that different amounts of the landscape would remain or become suitable in future. There was less agreement between models for C. glabratus than for P. versicolor. Main conclusions: In our example system, different resolution analyses result in different predictions about the ability of populations to survive climatic warming. Higher resolution analyses are not only likely to provide more accurate estimates of expected patterns of change, but also to highlight potential microclimatic refugia for the conservation of species that otherwise might appear to be threatened with regional or global extinction.