Introduction

1.0 INTRODUCTION

Climate provides fundamental limits on and opportunities for human activities and ecosystem

functioning within the Great Lakes region.  A changing climate could lead to alterations in the

frequency and severity of droughts and floods; water supply; air, soil, and water quality;

ecosystem health; human health; and resource use and the economy.  Climate change may act

through multiple pathways; interactions in and impacts on the Great Lakes ecosystem can be

dynamic and non-linear.  Within the Great Lakes watershed, there are already numerous

stressors that cause ecosystem change including land use change, pollution, eutrophication,

invasion of exotic species, and acid precipitation.  A changing climate should be considered as

another agent of change acting in concert with other ecosystem stresses (Easterling and Karl,

2001; Magnuson et al., 1996).

Recognizing that this emerging issue required a survey of the potential impacts and the ability to

adapt, the Great Lakes Water Quality Board commissioned a white paper to explore the

implications of a changing climate on the Great Lakes watershed (Figure 1-1).  The white paper

addresses four broad questions:

Figure 1-1. Great Lakes watershed  

1