School of Natural Resources and Environment

Dead zones

A satellite image of Lake Erie on Sept. 3, 2011, overlaid on a map of the lake and its tributaries. This image shows the bloom about six weeks after its initiation in the lake's western basin. On this date, it covers the entire western basin and is beginning to expand into the central basin. Map by Michigan Sea Grant.

The largest harmful algae bloom in Lake Erie's recorded history was likely caused by the confluence of changing farming practices and weather conditions that are expected to become more common in the future due to climate change. Rather than an isolated, one-time occurrence, it was more likely a harbinger of things to come, according to U-M researchers and other.