Patterns of coherent dynamics within and between lake districts at local to intercontinental scales

Spatial patterns of coherent inter-annual dynamics between lakes occur within and between lake districts at regional, continental, and even intercontinental scales. Climatic variability and change are external drivers of lake dynamics but individual lake ecosystems differentially filter these signals and alter their expression. When related to landscape position spatial patterns in coherence can be uniform, unstructured, or structured. A structured pattern emerges for chemical responses to drought in a lake district dominated by groundwater while a more uniform pattern emerges in a stream-flow dominated lake district. Near-surface water temperatures and ice dates have a uniform pattern within and even between some lake districts; near-bottom water temperatures have an unstructured pattern; water levels have a complex pattern. Coherence in ice dates declines with latitudinal distance between lakes, but some coherence persists even at intercontinental scales that appears related to long-term climate change and common large-scale climate drivers.