Snowfall event characteristics in the cordillera vilcanota , peru

1. Snowfall event characteristics in the cordillera vilcanota, peru Baker Perry1, Richard Poremba1, Anton Seimon1,2, Daniel Martin1, Ginger Kelly1, and Alfredo Tupayachi3 1Department of Geography and Planning, Appalachian State University 2Climate Change Institute, University of Maine, 3Universidad Nacional de San Antonio de Abád de Cusco 71st Eastern Snow Conference Boone, NC USA 5 June 2014

2. Cordillera Vilcanota

4. Background and Significance • Cordillera Vilcanota has been the site of significant research focused on: • Paleoclimatic reconstructions from Quelccaya ice cores (e.g., Thompson et al. 1985, Seimon 2003, Thompson et al. 2006 ) • Past glaciations and climate-glacier interactions (e.g., Mark et al. 2002) • Ecological response to climate change (e.g., Seimon et al. 2007) • Precipitation variability is a fundamental influence on past and current changes in the tropical Andes (Garreaud et al. 2003) • Precipitation type, amount, and timing controls surface albedo, which is critical to glacier mass balance (e.g., Francou et al. 2003) • Precipitation processes play a dominant role in influencing stable oxygen isotope ratios (δ18O) preserved in snow/ice stratigraphy (e.g., Vuille et al. 2008, Vimeux et al. 2009) • However, considerable uncertainty remains on the timing, precipitation type, and trajectories during events

5. Descriptions of Central Andean Regional Precipitation ?

6. Research Questions • What are the predominant precipitation types at ~ 5,000 m asland how do they vary by season? • Snow, graupel (phati in Quechua), rain/snow mix, rain • Whatisthedailytiming of snowfallevents in the Cordillera Vilcanota? Whenis heavy snowfallmostlikely to occur? • Whatare thedominantwinddirections and antecedentupstream air trajectoriesassociatedwithsnowfallevents?

7. Cusco International Airport: Hourly Precip Observations SENAMHI Stations: 2x Daily Observations 0000 and 1200 UTC Perry et al. 2014, Int J Clim

9. Don Pedro Godfredo with Precipitation Gauge (At Murmurani Alto 5,050 m asl) Quelccaya Icecap August 2010 10 cm diameter manual gauge

10. Murmurani Alto (5,050 m) Temp & Relative Humidity Sonic Snow Depth Parsivel Present Weather April 2012

11. OsjolloAnante Icecap (5,540 m) RM Young 05103 Alpine Wind Sensor Vaisala WXT 510 Multisensorwith Sonic Wind, Temperature, Relative Humidity, and Pressure April 2012

12. Snow and Graupel are the Primary Precipitation Types Rain is Very Infrequent, Less than 4% of Hours

13. Rapid Snow Ablation in Murmurani Alto April 2012

14. 5.9 mm/event 68% of total =Stratiform? 3.3 mm/event 32% of total =Convective? Sunrise Day Night Perry et al. 2014, Int J Clim

15. 73% of heavy events occur at night 59% of light events occur during day Perry et al. 2014, Int J Clim

16. Sunrise Day Night

17. Composite Trajectory Clusters for All Events in Cusco, 2004-2010 Cluster 5 8% of events 3.3 mm/event Cluster 1 50% of events 4.7 mm/event Cluster 3 19% of events 4.8 mm/event 58% of precipitation events at Cusco exhibit trajectories out of the NNW Cluster 2 14% of events 3.6 mm/event 83% of events are tied to weak low-level flow out of NNW, NE, and E Cluster 4 5% of events 4.8 mm/event Cluster 6 5% of events 8.7 mm/event Infrequent, yet heavy Perry et al. 2014, Int J Clim

18. Wind Speed and Direction During All Precipitation Events: 2012-2013 Wind Observations from OsjolloAnante Precipitation Observations from Murmurani Alto

19. Wind Speed and Direction During DJF Precipitation Events: 2012-2013 Wind Observations from OsjolloAnante Precipitation Observations from Murmurani Alto

20. Descriptions of Central Andean Regional Precipitation Perry et al. 2014, Int J Clim

21. Summary and Conclusions • Precipitation primarily falls as snow above 5,000 m, with graupel and heavily rimed snow crystals common. Rain and mixed precipitation are rare, accounting for less than 5% of total precipitation hours. • How will these values change in 2014-2015, with the possibility of a major El Niño and anassociatedelevatedfreezinglevel? • There were a total of 281 events between April 2012 and July 2013, with most of the heavy events occurring at night. • No hourlyprecipitationtotalsavailable, onlypresentweather. • What are the meteorological mechanisms responsible for the heavy nighttime stratiform precipitation? • Most precipitation events are associated with W and NW flow at Murmurani Alto and NW trajectories at Cusco. • In contrast to E flow as reported at othersites in the Central Andes, includingQuelccaya.

22. Paleoclimatic Implications • Much of the inference from the nearby Quelccaya ice core record presumes that the central Andean precipitation meteorology is fairly well understood. Our findings call that into question. • A reconsideration of the climatological inferences derived from Quelccaya (and possibly other tropical Andean ice cores) may be needed. • May result in improved paleoclimatic understanding? • Improved correlation with other paleoclimatic proxy records?

23. Research Activities: July to November 2014 • Install precipitation monitoring stations on the Quelccaya Icecap and at Chacaltaya (Cordillera Real), Bolivia. • Recruit and train additional citizen science precipitation observers in the Cordilleras Vilcanota and Cordillera Real. • Investigate the vertical structure of precipitation with weather balloon releases and a vertically-pointing radar. • Categorize snow particle type and degree of riming, which may provide insight to cloud microphysical processes. Minder et al. (2012)

24. Questions? • Acknowledgments • Sandra Yuter, Doug Hardy, Nelson Quispe, Marcos Andrade, Tracie Seimon, Jon Webb, Preston Sowell, Brooks Fisher, Karina Yager, Charles Rodda, Skylar Haines, Nico Robles, Ben Boore, Paul Carr, Dan Slayback, Don Pedro Godfredo, and Crispin family • Appalachian State University Board of Trustees International Research Travel Grant (2009), Office of International Education and Development (2010, 2012), Justin Brooks Fisher Foundation (2012), College of Arts & Sciences (2012) • NSF Grant AGS-1347179 (CAREER: MultiscaleInvestigations of Tropical AndeanPrecipitation)