Winter/Spring Runoff is Earlier, More Protracted, and Increasing in Volume in the Laurentian Great Lakes Basin
Abstract
The nature of winter/spring runoff has changed in streams worldwide due to climate change, particularly in temperate areas where winter/spring streamflow is dependent on snowpack. Such changes have the potential to affect receiving waters through changes in nutrient loading and mixing patterns. The Laurentian Great Lakes are an important freshwater resource for millions of people and have experienced a myriad of impacts due to climate change and other anthropogenic stressors. We analyzed 70 years of stream gauge data in the Great Lakes Basin to examine changes in the timing, duration, and volume of winter/spring runoff during the period 1950-2019. We found strong evidence for earlier runoff in each of the Great Lakes except Lake Erie, more protracted winter/spring runoff throughout the Great Lakes Basin, and a higher volume of runoff over time for all watersheds except Lake Superior. Our results demonstrate that runoff patterns have changed dramatically over the last seven decades in the Great Lakes Basin concomitant with previously published changes in precipitation and snowpack. Shifts towards earlier, more protracted, and more voluminous runoff may change nutrient loading and mixing patterns that influence primary producers, particularly in the nearshore areas of the Great Lakes.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2021
- Bibcode:
- 2021AGUFM.H53E..01H