Climate Change in the Mid-Coast Region

The natural resources and community infrastructure of the Mid-Coast region of Oregon may be susceptible to vulnerabilities caused by climate change stressors that are affecting temperature, precipitation, hydrology, sea level, and coastal ocean conditions in the Mid-Coast. The following projections are based on the 2019 study conducted by the Oregon Climate Change Research Institute (Dalton et al. 2019), the USACE 2020 Hydroclimate Vulnerability Assessment, and other resources. 

The following online resources are available for visualizing past and projected climate and hydrology:

(Summary from USACE 2020 Hydroclimate Vulnerability Assessment):

In general, changes in climate variables will likely lead to increased risk of more frequent and extreme climate driven phenomena such as droughts, floods, and/or fires. Rising ambient temperatures are projected to add a direct stress to ecological resources in the Mid-Coast’s natural areas. The warming temperature regimes will most likely lead to altered hydrologic patterns as well. Wet seasons will likely become wetter, and the dry seasons will experience even less precipitation and, more importantly, lower base flows in the surrounding tributary creeks and rivers. Drier conditions in the summertime will drive increased chance and severity of wildfires as exemplified in the recent historic fires experienced by the Mid-Coast in September 2020. Wetter conditions in the winter are likely to increase flooding in the flat lowland areas of the Mid-Coast. Areas denuded by increased wildfire will experience higher runoff and will likely lead to increased sediment transport in the rivers, as well as mudslides from unstable hills and escarpments. Changes in future hydroclimate metrics, such as lower summer streamflow, are likely to have direct and adverse impacts on Mid-Coast water quality and supply infrastructure. Future projections (see bullets below) point to increased summertime temperatures as well as less available streamflow. These conditions are likely to lead to future water supply shortfalls are likely to become more common, and there will be less water to replenish lakes and recharge ground water.

Climate Change Projections for the Mid-Coast of Oregon
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© 2020 Oregon Mid-Coast Water Planning Partnership