Acoustic Ecology 08 & 09
Soundscape & Quiet Atlas
National Park Service acoustic monitoring records sound pressure levels across 33 one-third-octave frequency bands, measuring weather, biophony, and human noise. Time-scrub 24-hour diurnal acoustic clocks from Olympic National Park to the sub-threshold silence of Haleakalā Crater.
Acoustic EcologyNational Park Service Natural Sounds Program
The Soundscape & Quiet Atlas
Quiet Atlas StatusPristine Natural Quiet
Station Code: OLYM-HOH-001 // Elevation 180m
Hoh Rain Forest (Upper River Basin)
Temperate Coniferous Rainforest · 47.8603° N, 123.9348° W
Natural Sound Audibility: 86.4%
Diurnal State: 06:00 // Dawn Chorus & Canopy AwakeningSound Pressure Level: 28.5 dBA
Complex polyphonic bird vocalizations echoing between ancient Sitka spruce trunks, cushioned by damp moss absorption.
Biophony & Geophony (99.2%)
- Pacific wren (Troglodytes pacificus)
- Varied thrush
- Conifer needle water dripping
- Distant Hoh River bedload
Anthrophony (Incursion)
- None detected
Calibrated 1/3-Octave Acoustic Spectrum (20 Hz – 20 kHz):
25
50
100
200
400
800
1.25k
2k
3.15k
5k
8k
12.5k
16k
20k
Topographic Acoustic Profile
“Glacial valley topography and temperate rainforest precipitation contours shape how dense epiphyte moss blankets act as natural broad-spectrum acoustic absorbers.”