Evaluating multiple historical climate products in ecological models under current and projected temperatures

Area of Science:

• Ecology
• Climate Science
• Geospatial Analysis

Background:

• Gridded historical climate products (GHCPs) are increasingly used for ecological modeling and climate change impact assessments.
• Uncertainty in climate projections often focuses on global circulation models (GCMs) and emissions scenarios, overlooking GHCP choice implications.
• Differences among GHCPs can significantly affect ecological predictions, yet this uncertainty source is less explored.

Purpose of the Study:

• To assess the impact of using different GHCPs on ecological models.
• To compare the performance of observed versus GHCP temperature data, including elevation adjustments.
• To identify areas with high prediction uncertainty under current and future climate scenarios.

Main Methods:

• Modeled plant canopy cover and tree basal area in central Alaska using observed and seven GHCPs' July temperature data.
• Compared model fit using raw, adjusted, and observed temperature data.
• Analyzed prediction differences and variations across GHCPs under current and +2°C warming scenarios.

Main Results:

• Elevation-adjusted temperature models showed better fit than raw temperature models.
• Elevation-adjusted models using observed or GHCP temperatures performed similarly.
• GHCPs showed good agreement but with notable differences at mid-elevations, amplified under warming.

Conclusions:

• GHCPs generally perform well in ecological models, but variation exists, particularly in mid-elevation areas.
• Using a single GHCP can obscure important prediction uncertainties.
• Employing multiple GHCPs is recommended to capture broader uncertainty beyond standard prediction intervals, especially for conservation planning.