Guy F. Atkinson Distinguished Lecture Series: "Where Deserts and Mountains Collide: the Implications of Accelerated Snowmelt by Desert Dust"
| What | Event |
|---|---|
| When |
2009-04-30 from 15:30 to 17:00 |
| Where | 295 FASB Auditorium |
| Contact Phone | 801-581-7162 |
Guest Speaker:
Thomas Painter
University of Utah
Department of Geography
Director - Snow Optics Lab
Abstract: Dust emitted from natural and disturbed lands frequently deposits to mountain snow cover through dry and wet deposition, particularly in spring when synoptic scale storms entrain material from recently dried surfaces. Dust decreases snow spectral albedo, primarily in the visible wavelengths where the imaginary parts of the complex refractive indices of dust and ice have the greatest contrast. This surface radiative forcing accelerates melt and contributes to the snow-albedo feedback. With in situ and remotely sensed measurements, we have shown that snow cover duration in the Colorado River Basin is shortened by order 1 month. In turn, the snow-albedo feedback is enhanced through a 2nd indirect effect of 150 W/m2 when the darker substrate is exposed. Most critically though, we find that the water yield from the Upper Colorado River has been decreased by ~5% due to this shortening of the snowmelt season.
Thomas Painter
University of Utah
Department of Geography
Director - Snow Optics Lab
Abstract: Dust emitted from natural and disturbed lands frequently deposits to mountain snow cover through dry and wet deposition, particularly in spring when synoptic scale storms entrain material from recently dried surfaces. Dust decreases snow spectral albedo, primarily in the visible wavelengths where the imaginary parts of the complex refractive indices of dust and ice have the greatest contrast. This surface radiative forcing accelerates melt and contributes to the snow-albedo feedback. With in situ and remotely sensed measurements, we have shown that snow cover duration in the Colorado River Basin is shortened by order 1 month. In turn, the snow-albedo feedback is enhanced through a 2nd indirect effect of 150 W/m2 when the darker substrate is exposed. Most critically though, we find that the water yield from the Upper Colorado River has been decreased by ~5% due to this shortening of the snowmelt season.
