The Center for Snow and Avalanche Studies (CSAS) is home to “CODOS”, the Colorado Dust-on-Snow program, an applied science effort on behalf of Colorado and regional water management agencies. CSAS operates the Senator Beck Basin study area at Red Mountain Pass as the primary sentry site for the CODOS program. With direct funding from stakeholders, CSAS monitors the presence/absence of dust layers at 11 mountain pass locations throughout Colorado. Using those observations, data from nearby Snotel sites, and weather forecasts, the CODOS program issues a series of “Update” analyses of how dust-on-snow is likely to influence snowmelt timing and rates during the runoff season.
Data
About CODOS
In our WY 2016 Summary report, and in presentations during Fall 2015, we introduced a refined approach to understanding the impacts of dust-on-snow on Colorado snowmelt runoff ‘patterns’, as reflected in headwater hydrographs. CODOS has observed dust conditions and snowmelt behaviors in Colorado since 2006. It has become apparent, in that period, that the interactions of three primary factors – March 1 SWE, spring dust intensity, and spring weather (precipitation) – comprise a “dust enhanced snowmelt runoff space” (Figure 1). First and foremost among those factors, snowcover water content (i.e., snow water equivalence, or SWE) in Colorado watersheds dictates snowmelt runoff yields and a basin hydrograph’s overall magnitude. March 1 SWE conditions offer a meaningful benchmark in seasonal snowpack formation that also coincides with the onset of ‘dust season’, as 80% of the dust-on-snow events observed by CODOS since 2005 have occurred in March, April and May.
Then, although the presence of dark mineral dust at or near the snowcover surface during daytime always accelerates snowmelt rates by reducing snow albedo and increasing absorption of solar radiation, dust-on-snow does not automatically result in an early runoff cycle. Considerable variation in the overall timing and rates of snowmelt from equivalent snowpacks containing equivalent dust can occur as a result of differences in the number and size of March, April, and May snowfalls. A dry spring, with fewer and smaller spring snowfalls, prolongs dust layer exposure and maximizes dust impacts on snowmelt. A wet spring with frequent, large spring snowfalls results in repeatedly burying exposed dust and restoring high snow albedo, delaying the full impact of dust until a later period of prolonged dust emergence. Hence, besides contributing additional snow to the seasonal total, March, April and May precipitation plays a key role in determining the timing and rate of dust-enhanced snowmelt runoff, from a given snowpack containing dust.
CODOS has now observed twelve seasons of dust-enhanced snowmelt runoff behavior throughout the Colorado mountains (WY 2006-2017). Hydrographs at headwater stream gauges have been evaluated and classified within the framework of this dust enhanced snowmelt runoff space utilizing a 3 x 3 x 3 cell matrix corresponding to general characterizations of SWE, dust intensity, and spring weather, as shown in Figure 1.
Figure 1: a conceptual dust enhanced snowmelt runoff model integrating the interactions of March 1 SWE, dust intensity, and spring precipitation.
In this approach, March 1 SWE classifications are based on NRCS 1981-2010 statistics for Snotel stations proximal to the eleven sites monitored by CODOS. “Average SWE” is defined as a Snotel site’s 1981-2010 median value for March 1, +/- 10%. Values outside that 90-110% of median condition are classified as either High or Low March 1 SWE.
Dust intensity classification is based on dust conditions observed since 2005 at CSAS’s Senator Beck Basin Study Area (SBB). Dust intensity characterization at SBB represents a difficult challenge since dust deposition intensity has, overall, increased during the period of CODOS observations. As such, the notion of “average” dust intensity has changed over that period and may not yet have stabilized. During the past four seasons, in collaboration with USGS, CODOS has collected and analyzed dust mass loading samples and quantified dust loading at SBB. Those measurements have enabled calibration, from snowpit observations and photographs, of prior seasons at SBB using this three-part classification scheme.
Although still a short period of record, during a period of rapidly changing conditions, these characterizations may be sufficient to distinguish one season from another in this tree-part classification scheme. Within this period of record (2006-2016) Water Year 2007 is classified as “Min+” dust intensity and WY 2006 and WY 2010 are considered “Max-“. (Prior WY’s 2004 and 2005 might also be classified as “Min” dust seasons at SBB, relative to subsequent years, but are not included in these analyses due to incomplete observations.) It is further understood that dust intensity at SBB is typically stronger than observed at sites farther downwind, to the north and east. (CODOS resources have not enabled the collection of dust mass loading samples comparable in quality and frequency to those collected at SBB.) Dust intensity characterizations at sites beyond SBB are, in this classification, both tied to “Min”, “Avg”, and “Max” conditions at SBB as well as being site specific and relative to observed “all layers merged” intensity near the end of the season at the given site (i.e., of generally lower ‘absolute’ intensity than SBB).
Spring precipitation classifications are also based on NRCS 1981-2010 statistics for Snotel stations proximal to the eleven sites monitored by CODOS. Average precipitation is defined as a Snotel site’s 1981-2010 median total of March, April, and May measured precipitation, +/- 15%. Values outside that 85-115% of median condition are classified either Wet or Dry. This more generous range in Average precipitation values is utilized in order to capture the larger spatial variation in spring precipitation from convective sources. Given the generally high elevations of these Snotel sites, March, April, and May precipitation is assumed to be snow and no parsing of rain precipitation was attempted. Analyses of annual variances in total March/April/May precipitation since 2006 have been performed and are now posted on all CODOS site webpages.
Using these rules and procedures, the following table classifies WY 2017 conditions at 19 headwater stream gauges associated with the twelve CODOS monitoring sites (including Senator Beck Basin) and associated Snotels that CODOS monitors:
All other Water Years have been similarly classified in the Excel workbook Runoff_Space_by_Region_and_WY.xlsx. Also, similar classifications were performed for each of the headwater stream gauges, by Water Year in Runoff_Space_by_Watershed.xlsx. Finally, links to presentations of these individual stream gauge classification matrices are listed below. They can also be found in the Dust Enhanced Runoff Classification discussion of each CODOS site.
Wind rose for dust-on-snow event #12 (D12) of WY 2012
Click on each date in the table below for a wind rose image during the dust event (reduced-size example on right). We have estimated beginning and end times of each event based on observations from Silverton, CO. It is reasonable to assume that our skill at detecting dust-on-snow events has improved over time and that we may have failed to observe very small events during the early years of this work. Custom wind roses can be created using our wind rose tool.
D1 |
D2 |
D3 |
D4 |
D5 |
D6 |
D7 |
D8 |
D9 |
D10 |
D11 |
D12 |
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WY 2018 | |||||||||||||||
WY 2017 | |||||||||||||||
WY 2016 | |||||||||||||||
WY 2015 | |||||||||||||||
WY 2014 | |||||||||||||||
WY 2013 | |||||||||||||||
WY 2012 |
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WY 2011 | |||||||||||||||
WY 2010 | |||||||||||||||
WY 2009 | |||||||||||||||
WY 2008 | |||||||||||||||
WY 2007 | |||||||||||||||
WY 2006 | 12/23 |
02/15 |
03/26 |
04/05 |
04/15 |
04/17 |
05/22 |
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WY 2005 | 03/23 |
04/04 |
04/08 |
05/09 |
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WY 2004 | 04/17 |
04/28 |
05/11 |
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WY 2003 | 02/03 |
02/22 |
04/02 |
Dust-on-Snow Events Documented per Month, by Winter Senator Beck Basin Study Area at Red Mountain Pass – San Juan Mountains |
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Oct | Nov | Dec | Jan | Feb | Mar | Apr | May | Jun | Total | Wet | Dry | |
WY 2018 | 0 | 0 | 1 | 0 | 1 | 1 | 4 | |||||
WY 2017 | 0 | 0 | 0 | 0 | 0 | 3 | 1 | 0 | 0 | 4 | 3 | 1 |
WY 2016 | 0 | 0 | 1 | 0 | 1 | 2 | 2 | 0 | 0 | 6 | 6 | 0 |
WY 2015 | 0 | 0 | 0 | 0 | 0 | 0 | 3 | 0 | 0 | 3 | 1 | 2 |
WY 2014 | 0 | 0 | 0 | 0 | 1 | 3 | 3 | 1 | 2 | 10 | 6 | 4 |
WY 2013 | 0 | 1 | 0 | 0 | 1 | 3 | 4 | 1 | 0 | 10 | 6 | 4 |
WY 2012 | 0 | 2 | 1 | 0 | 0 | 3 | 2 | 4 | 0 | 12 | 3 | 9 |
WY 2011 | 0 | 0 | 0 | 0 | 1 | 3 | 3 | 4 | 0 | 11 | 7 | 4 |
WY 2010 | 1 | 0 | 0 | 0 | 0 | 1 | 4 | 3 | 0 | 9 | 5 | 4 |
WY 2009 | 1 | 0 | 1 | 0 | 1 | 4 | 5 | 0 | 0 | 12 | 7 | 5 |
WY 2008 | 0 | 0 | 0 | 0 | 0 | 3 | 3 | 1 | 0 | 7 | 2 | 5 |
WY 2007 | 0 | 0 | 1 | 0 | 1 | 1 | 3 | 1 | 1 | 8 | 7 | 1 |
WY 2006 | 0 | 0 | 1 | 0 | 1 | 1 | 3 | 2 | 0 | 8 | 6 | 2 |
WY 2005 | 0 | 0 | 0 | 0 | 0 | 1 | 2 | 1 | 0 | 4 | 3 | 1 |
WY 2004 | 2 | 1 | 3 | na | na | |||||||
WY 2003 | 2 | 1 | 3 | na | na |
Below are windroses of all dust-on-snow events observed at Senator Beck Basin beginning WY 2007. The most recent is at the end.
July 25: CODOS WY 2014 Summary
June 15: CODOS Dust Alert - Event D9-WY2014
June 10: CODOS Update - Dust forcing high snowmelt rates statewide
May 29: CODOS Alert for imminent, dust-enhanced surging in snowmelt runoff
May 26: CODOS Update - Upper Gunnison River and North Fork of the Gunnison
May 22: CODOS Update – Senator Beck Basin and Western San Juan Mountains
May 12: CODOS Dust Alert - D8
April 28: CODOS Update - Tour Summary April 23-26
April 28: CODOS Alert for events D6 and D7
April 23: Dust event averted
April 18: Dust event D6-WY2014 is increasingly likely next Tues/Weds
Berthoud | Grand Mesa | Loveland Pass | Hoosier | McClure | Senator Beck Basin | Park Cone | Spring Creek | Willow Creek | Wolf Creek
June 17, 2013: Colorado Dust-on-Snow Program WY 2013 Final Report
May 24, 2013: CODOS Update - D10, North to South Variation in Snowmelt
May 12, 2013: CODOS Update for Northern, Front Range, and Grand Mesa CODOS sites
May 7, 2013: CODOS Update for early May conditions at Senator Beck Basin
May 6, 2013: Dust-induced snow surface roughness: time lapse photography and more
April 30-May 1 CODOS Tour of southern sites:
April 30: Swamp Angel Study Plot
: McClure Pass
: Park Cone
May 1 : Spring Creek Pass
: Wolf Creek Pass
April 30, 2013: CODOS Dust Alert - D9, a very minor event at Senator Beck Basin
April 26, 2013: Dust-induced Snow Surface Roughness
April 24, 2013: CODOS Update - D6 and D8 Dust Near Top of Snowpacks Statewide
April 18, 2013: CODOS Dust Alert - D8 event finally over
April 16, 2013: CODOS Dust Alert - D8 now in 36th hour and ongoing
April 14, 2013: CODOS Dust-on-Snow Event Alert - D7-WY 2013, April 13-14
April 10-13 CODOS Tour: Summary
April 10: Swamp Angel Study Plot
April 11: Grand Mesa Study Plot
: Park Cone
April 12: Rabbit Ears Pass
: Willow Creek Pass
: Berthoud Summit
: Spring Creek Pass
: Wolf Creek Pass
April 13: Hoosier Pass
: Grizzly Peak
: McClure Pass
April 9, 2013: D6 A Major Deposition, Many Reports
April 8, 2013: CODOS Alert - Dust-on-Snow Event D6-WY2013
March 25, 2013: CODOS Tour Summary
March 22-23, 2013: CODOS Tour (part 2):
March 22: Swamp Angel Study Plot
March 22: Grand Mesa Study Plot
March 23: Spring Creek Pass
March 23: Wolf Creek Pass
March 22, 2013: Alert for event D5-2013
March 18-21, 2013 CODOS Tour (part 1):
March 19: Berthoud Summit
March 19: Grizzly Peak
March 18: Hoosier Pass
March 20: McClure Pass
March 18: Park Cone
March 20: Rabbit Ears Pass
March 19: Willow Creek Pass
March 21, 2013: Alert for event D4-WY2013
March 8, 2013: D3 Alert and new research on dust enhancement of precipitation
March 1, 2013: Conditions at Senator Beck Basin
February 19, 2013: Update - D2 had limited extent, approaching winter storm to blanket Colorado Plateau
February 9, 2013: D2 Alert
January 25, 2013: Update
January 1, 2013: CODOS Update for New Years 2013
November 30, 2012: Dry start to Water Year 2013
November 9, 2012: 1st dust event of the season (D1)
November 4, 2012: Dry October; Weather and climate websites
Sept 14, 2012: Another important new dust science article just out
September 5, 2012: Recent dust science articles
2012 Final Report: A Case Study in Interannual Variability of Colorado Snowpack and the Role of Desert Dust
Berthoud Summit: WY 2012 Summary | May 2 | April 10 | March 28 | March 15
Grand Mesa: WY 2012 Summary | May 1 | April 5 | March 28 | March 16
Grizzly Peak: WY 2012 Summary | April 27 | April 10 | March 28 | March 15
Hoosier Pass: WY 2012 Summary | May 2 | April 9 | March 28 | March 14
McClure Pass: WY 2012 Summary | April 27 | April 11 | March 28 | March 16
Park Cone: WY 2012 Summary | April 27 | April 9 | March 28 | March 14
Rabbit Ears Pass: WY 2012 Summary | May 2 | April 10 | March 28 | March 15
Senator Beck Basin: WY 2012 Summary | April 23 | April 7-8 | March 26-27 | March 5-16
Spring Creek Pass: WY 2012 Summary | April 9 | March 28 | March 17
Willow Creek Pass: WY 2012 Summary | April 27 | April 10 | March 28 | March 15
Wolf Creek Pass: WY 2012 Summary | May 1 | April 9 | March 28 | March 17
Prior Year Updates:
Water Year 2012 CODOS Updates (pdf, 9.5 mb)
Water Year 2011 CODOS Updates (pdf, 5.4mb)
Water Year 2010 CODOS Updates (pdf, 5.4mb)
Water Year 2009 CODOS Updates (pdf, 2.3mb)
Water Year 2008 CODOS Updates (pdf, 0.8mb)
Using the NRCS SNOTEL data, CSAS has assembled datasets presenting Peak SWE and subsequent snowmelt rates at 16 SNOTEL sites distributed throughout Colorado, 11 of which are near a CODOS monitoring site. The remaining 4 SNOTEL sites are in locations between CODOS sites, representing additional terrain. Water Year 2006-2017 Snotel data were examined since this period spans our efforts to monitor dust-on-snow deposition and its effects on Colorado snowmelt behavior. Mean values are calculated for annual datasets representing all fifteen sites, but those averages are intended to be merely descriptive of those years, and not predictive of past or future years. The datasets include:
This workbook contains individual spreadsheets for Water Years 2006-2017 and also includes summaries of all 11 years:
WY_SNOTEL_Summaries.xls
Each of these workbooks contain spreadsheets for each year, including a summary aggregating all years for each site:
Beartown | Berthoud Summit | Grizzly Peak | Hoosier Pass | Independence Pass | Lizard Head Pass | McClure Pass | Mesa Lakes | Park Cone | Rabbit Ears Pass | Red Mountain Pass | Schofield Pass | Slumgullion Pass | Upper San Juan | Willow Creek Pass | Wolf Creek Pass
We invite you to submit your own dust-on-snow observations. Observations of "no dust" are also welcome. If you have photos, please include a link here or email as attachments to jderry@snowstudies.org
For more details, see the CODOS site atlas (pdf) and our Google Earth KMZ file. Contact jderry@snowstudies.org for more information. The first image below is a spring 2009 MODIS satellite image of Colorado's mountain ranges. The cloud tops in the bottom right of the image approximate the color of clean snow.
Senator Beck Basin is outlined in red, with the locations of the four study plots in yellow (from left to right): Senator Beck Study Plot (SBSP), Swamp Angel Study Plot (SASP), Senator Beck Stream Gauge (SBSG), Putney Study Plot (PTSP)
Scholarly Dust-on-Snow Related Publications (assisted by CSAS/CODOS):
Painter, T. H,S. M. Skiles, J. S. Deems, W. T. Brandt, and J. Dozier (2017), Variation in rising limb of Colorado River snowmelt runoff hydrograph controlled by dust radiative forcing in snow, Geophys. Res. Lett.,doi: 10.1002/2017GL075826
Skiles, S.M. and Painter, T. (2017) ‘Daily evolution in dust and black carbon content, snow grain size, and snow albedo during snowmelt, Rocky Mountains, Colorado’, Journal of Glaciology, 63(237), pp. 118–132. doi: 10.1017/jog.2016.125.
Skiles, S.M., Painter, T. and Okin, G.S. (2017) ‘A method to retrieve the spectral complex refractive index and single scattering optical properties of dust deposited in mountain snow’, Journal of Glaciology, 63(237), pp. 133–147. doi: 10.1017/jog.2016.126.
Guy, Z.M., Deems, J. (2016), Unusual Dry Slab Avalanche Releases Involving Dust-on-Snow Layers in Colorado, Proceedings, International Snow Science Workshop, Breckenridge, Colorado.
Axson, J. L., H. Shen, A. L. Bondy, C. C. Landry, J. Welz, J. M. Creamean, A. P. Ault (2016), Transported Mineral Dust Deposition Case Study at a Hydrologically Sensitive Mountain Site: Size and Composition Shifts in Ambient Aerosol and Snowpack, Aerosol and Air Quality Res., 16: 555-567, doi:10.4209/aaqr.2015.05.0346
Oaida, C. M., Y. Xue, M. G. Flanner, S. M. Skiles, F. De Sales, and T. H. Painter (2015), Improving snow albedo processes in WRF/SSiB regional climate model to assess impact of dust and black carbon in snow on surface energy balance and hydrology over western U.S., J. Geophys. Res. Atmos., 120, 3228–3248, doi:10.1002/2014JD022444
Landry, C. C., K. A. Buck, M. S. Raleigh, and M. P. Clark (2014), Mountain system monitoring at Senator Beck Basin, San Juan Mountains, Colorado: A new integrative data source to develop and evaluate models of snow and hydrologic processes, Water Resour. Res., 50, doi:10.1002/2013WR013711.
Bryant, A. B., T. H. Painter, J. S. Deems, and S. M. Bender (2013), Impact of dust radiative forcing in snow on accuracy of operational runoff prediction in the Upper Colorado River Basin, Geophys. Res. Lett., 40, doi: 10.1002/grl.50773, 2013.
J. Brahney, A.P. Ballantyne, C. Sievers, J.C. Neff. Increasing Ca2+ deposition in the western US: the role of mineral aerosols. Aeolian Research (2013), http://dx.doi.org/10.1016/j.aeolia.2013.04.003
Deems, J. S., T.H. Painter, J.J. Barsugli, J. Belnap, and B. Udall (2013), Combined impacts of current and future dust deposition and regional warming on Colorado River Basin snow dynamics and hydrology, Hydrol. Earth Syst. Sci., 17, 4401-4413, doi:10.5194/hess-17-4401-2013.
Painter, T. H., A. C. Bryant, and S. M. Skiles (2012), Radiative forcing by light absorbing impurities in snow from MODIS surface reflectance data, Geophys. Res. Lett., 39, L17502, doi:10.1029/2012GL052457.
Skiles, S. M., T. H. Painter, J. S. Deems, A. C. Bryant, and C. Landry (2012), Dust radiative forcing in snow of the Upper Colorado River Basin: Part II. Interannual variability in radiative forcing and snowmelt rates, Water Resour. Res., doi:10.1029/2012WR011986.
Painter, T. H., S. M. Skiles, J. S. Deems, A. C. Bryant, and C. Landry (2012), Dust radiative forcing in snow of the Upper Colorado River Basin: Part I. A 6 year record of energy balance, radiation, and dust concentrations, Water Resour. Res., doi:10.1029/2012WR011985.
Painter, T. H., J. Deems, J. Belnap, A. Hamlet, C. C. Landry, and B. Udall (2010), Response of Colorado River runoff to dust radiative forcing in snow, Proceedings of the National Academy of Sciences, published ahead of print September 20, 2010,doi:10.1073/pnas.0913139107.
Lawrence, C. R., T. H. Painter, C. C. Landry, and J. C. Neff (2010), Contemporary geochemical composition and flux of aeolian dust to the San Juan Mountains, Colorado, United States, Journal of Geophysical Research, 115, G03007, doi:10.1029/2009JG001077.
Steltzer, H., C. Landry, T. H. Painter, J. Anderson, and E. Ayres. 2009.Biological consequences of earlier snowmelt from desert dust deposition in alpine landscapes. Proceedings of the National Academy of Sciences. 106: 11629-11634, doi_10.1073_pnas.0900758106.
Neff, J.C., A.P. Ballantyne, G.L. Farmer, N.M. Mahowald, J.L. Conroy, C.C. Landry, J.T. Overpeck, T.H. Painter, C.R. Lawrence and R.L. Reynolds. 2008. Increasing eolian dust deposition in the western United States linked to human activity, Nature Geoscience, Vol. 1, No. 3, pp. 189-195, March 2008, doi: 10.1038/ngeo136
Painter, T. H., A. P. Barrett, C. C. Landry, J. C. Neff, M. P. Cassidy, C. R. Lawrence, K. P. Thatcher, L. Farmer. (2007) Impact of disturbed desert soils on duration of mountain snow cover. Geophysical Research Letters. V34, 12, L12502, 10.1029/2007GL030208.
Student Theses:
McKenzie Skiles, Dust and Black Carbon Radiative Forcing Controls on Snowmelt in the Colorado River Basin, Department of Geography, University of California-Los Angeles, (PhD 2014).
Please contact Jeff Derry (jderry@snowstudies.org ) if your agency/organization is interested in joining the CODOS stakeholders.
CODOS Funders | ||||||||||
WY '07 |
WY '08 |
WY '09 |
WY '10 |
WY '11 |
WY '12 |
WY '13 |
WY '14 |
WY '15 |
WY '16 |
|
Animas-La Plata Water Conservancy District | 500 |
600 |
600 |
400 |
500 |
|||||
Bureau of Rec., Western Colorado Area Office | 5,000 |
8,000 |
7,500 |
|||||||
Bureau of Rec., Lower Colorado Region | 7,000 |
10,000 |
10,000 |
10,000 |
10,000 |
10,000 |
10,000 |
|||
Bureau of Rec., Eastern Colorado Area Office | 2,500 |
2,500 |
2,500 |
2,500 |
2,500 |
2,500 |
||||
City of Grand Junction | 2,500 |
2,500 |
2,500 |
2,500 |
2,500 |
2,500 |
||||
Colorado River Water Conservation District | 8,000 |
8,000 |
8,000 |
10,000 |
10,000 |
10,000 |
15,000 |
15,000 |
20,000 |
20,000 |
Colorado Water Conservation Board | 28,034 |
15,000 |
50,000 |
50,000 |
40,000 |
25,000 |
||||
Denver Water | 2,500 |
2,500 |
2,500 |
5,000 |
5,000 |
5,000 |
6,000 |
6,000 |
6,000 |
6,000 |
Dolores Water Conservancy District | 600 |
600 |
750 |
750 |
1,000 |
1,000 |
1,000 |
|||
Northern Colorado Water Conservancy District | 1,500 |
2,500 |
2,000 |
|||||||
Rio Grande Water Conservation District | 3,000 |
4,000 |
5,000 |
5,000 |
5,000 |
5,000 |
5,000 |
5,000 |
5,000 |
|
Southwestern Water Conservation District | 5,000 |
5,000 |
4,000 |
5,000 |
5,000 |
5,000 |
5,000 |
5,000 |
5,000 |
5,000 |
Tri-County Water Conservancy District | 1,000 |
1,000 |
1,500 |
2,500 |
2,500 |
2,500 |
2,500 |
2,500 |
2,500 |
2,500 |
Upper Gunnison River Water Conservancy District | 5,000 |
7,500 |
7,500 |
7,500 |
7,500 |
7,500 |
5,000 |
7,500 |
7,500 |
|
Western Water Assessment – Univ. of Colorado | 20,072 |
The Center for Snow and Avalanche Studies is home to “CODOS”, the Colorado Dust-on-Snow program, an applied science effort funded directly by a collaboration of Colorado and regional water management agencies. Research funded in 2004 by National Science Foundation Grant #ATM0431955 showed that winter and spring depositions of desert dust from the Colorado Plateau onto Colorado’s mountain snowpacks can dramatically reduce snowcover albedo, advance snowmelt timing, enhance snowmelt runoff intensity, and decrease snowmelt runoff yields (see Geophysical Research Letter, 2007 and Proceedings of the National Academy of Sciences, 2010).
CSAS engaged Colorado’s water management community during the summer of 2006 and has been presenting these findings ever since, at quarterly board meetings of local water districts, Colorado Water Congress and Colorado Water Workshop sessions, regional IBCC Colorado Roundtable sessions, and other technical meetings hosted by the Bureau of Reclamation. With direct funding support from those stakeholders, CODOS monitors the presence/absence of dust layers at ten mountain pass locations throughout the State. With those data, and data from nearby Snotel sites, and given the weather forecasts for those watersheds, CODOS provides its funders and their agency partners with a series of “Update” analyses of how dust-on-snow is likely to influence snowmelt timing and rates during the snowmelt runoff season. That information assists reservoir operators, municipal and agricultural water providers, flood risk managers, and others at local, State, and Federal agencies responsible for managing the spring runoff water that is so vital to Colorado and to states downstream on the Colorado, Rio Grande, North and South Platte, and Arkansas rivers.
Below are links to a selection of CODOS images. Photos for the additional CODOS sites are available on each site page. Displayed is a selection of photos spanning several years of the CODOS program at Senator Beck Basin. All Photos © Center for Snow and Avalanche Studies. Contact Amy Dickinson for more information.
Click each photo for a larger version and for captions. Mouse over the large images to display captions, including the date of the photo.