Hyper-dry conditions provide new insights into the cause of extreme floods after wildfire
Catena
Links
- More information: Publisher Index Page (via DOI)
- Download citation as: RIS | Dublin Core
Abstract
A catastrophic wildfire in the foothills of the Rocky Mountains near Boulder, Colorado provided a unique opportunity to investigate soil conditions immediately after a wildfire and before alteration by rainfall. Measurements of near-surface (< 6 cm) soil properties (temperature, volumetric soil-water content, θ; and matric suction, ψ), rainfall, and wind velocity were started 8 days after the wildfire began. These measurements established that hyper-dryconditions (θ < ~ 0.02 cm3 cm-3; ψ > ~ 3 x 105 cm) existed and provided an in-situ retention curve for these conditions. These conditions exacerbate the effects of water repellency (natural and fire-induced) and limit the effectiveness of capillarity and gravity driven infiltration into fire-affected soils. The important consequence is that given hyper-dryconditions, the critical rewetting process before the first rain is restricted to the diffusion–adsorption of water-vapor. This process typically has a time scale of days to weeks (especially when the hydrologic effects of the ash layer are included) that is longer than the typical time scale (minutes to hours) of some rainstorms, such that under hyper-dryconditions essentially no rain infiltrates. The existence of hyper-dryconditions provides insight into why, frequently during the first rain storm after a wildfire, nearly all rainfall becomes runoff causing extremefloods and debris flows.
Suggested Citation
Moody, J.A., Ebel, B.A., 2012, Hyper-dry conditions provide new insights into the cause of extreme floods after wildfire: Catena, v. 93, p. 58-63, https://doi.org/10.1016/j.catena.2012.01.006.
| Publication type | Article |
|---|---|
| Publication Subtype | Journal Article |
| Title | Hyper-dry conditions provide new insights into the cause of extreme floods after wildfire |
| Series title | Catena |
| DOI | 10.1016/j.catena.2012.01.006 |
| Volume | 93 |
| Year Published | 2012 |
| Language | English |
| Publisher | Elsevier |
| Publisher location | Amsterdam, Netherlands |
| Contributing office(s) | Branch of Regional Research-Central Region |
| Description | 6 p. |
| Larger Work Type | Article |
| Larger Work Subtype | Journal Article |
| Larger Work Title | Catena |
| First page | 58 |
| Last page | 63 |
| Country | United States |
| State | Colorado |
| City | Boulder |
| Other Geospatial | Rocky Mountains |