Landscape response to climate change and its role in infrastructure protection and management at Mount Rainier National Park
Beason SR, Kennard PM, Abbe TB, Walkup LC. 2011. Landscape response to climate change and its role in infrastructure protection and management at Mount Rainier National Park. Park Science. 28(2):31–35
Mount Rainier is a 4,392 m (14,410 ft) volcano that presents considerable risks from numerous natural hazards. While most of the spectacular hazards associated with volcanoes happen infrequently and are usually preceded by warning signs, flooding and debris flows occur more often and sometimes without warning. Devastating floods at Mount Rainier National Park, Washington, have increased in frequency in the last decade and have led to tens of millions of dollars’ worth of damage to park infrastructure. Major rivers at Mount Rainier are fed by glaciers and are aggrading, or filling in with sediment, at rates of up to 1.8 m (6 ft) per decade whereas historically they were aggrading at 7–13 cm (3–5 in) per decade. As a consequence of regional climate warming, all of the 25 glaciers in the park are retreating and thinning; as glaciers retreat, unconsolidated and unstable sediment is exposed and mobilized into rivers, which causes aggradation downstream. This tremendous increase in aggradation is filling in stream channels and enlarging floodplains, which leads to more frequent catastrophic shifts (avulsions) in the location of river channels. Avulsions tend to destroy park infrastructure and disturb riparian forest habitat. Future climate warming scenarios published by the University of Washington’s Climate Impacts Group anticipate increased year-round temperatures with no significant change in yearly precipitation. These factors favor glacial retreat, decreased snowpack, increased debris flows, and a much larger variation in the occurrence and magnitude of regional flooding. For infrastructure management and planning, protection of natural resources, appreciation of riparian processes, and overall employee and visitor safety, we need to understand the changing river hydraulics because of excess sediment supply and its ties to climate change.
- Type
- Journal Article
- Authors
- Beason, Scott; Kennard, Paul; Abbe, Tim; Walkup, Laura
- Units
- MORA , NRSS
- Keywords
- Aggradation, Climate Change, Debris Flows, Floods, Glacial retreat, landscape maintenance, Mount Rainier NP, PWR-toolkit, PWR-Toolkit-Facilities, Rivers