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Lake-Effect over Lakes Smaller than the Great Lakes Image:18 Jan. 2003 Burlington, VT Neil Laird Associate Professor Department of Geoscience, Hobart & William Smith Colleges, Geneva , NY Acknowledgement:
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Lake-Effect over Lakes Smaller than the Great Lakes Image:18 Jan. 2003 Burlington, VT Neil Laird Associate Professor Department of Geoscience, Hobart & William Smith Colleges, Geneva, NY Acknowledgement: Jared Desrochers, Indiana Univ. Melissa Payer, Univ. at Albany Ryan Sobash, Oklahoma Univ. Natasha Hodas, Rutgers Univ. Jessica Popp, William Smith College Benjamin Albright, Penn State Univ. Sara Ganetis, Univ. at Albany Andrew Stieneke, N. C. State Univ. Alicia Bentley, Univ. at Albany Samantha Santeiu, Iowa State Univ. Portions of this research were completed as part of the 2005, 2006, 2007, 2009 and 2010 undergraduate summer research program at Hobart & William Smith Colleges. Funding for these projects were provided by the National Science Foundation and the Provost's Office of Hobart & William Smith Colleges. Image courtesy of CAMNET operated by the Northeast States for Coordinated Air Use Management
Lake-Effect over Small Lakes – Why should we care? • Few studies have investigated lake-effect snow storms associated with lakes smaller than the Great Lakes • Studies have shown lake-effect storms on small lakes can be significantExamples include: • Great Salt Lake 15-hr event resulted in 36 cm (14 inches)Steenburgh and Onton (2001) • Lake Tahoe 2-day event produced 53 cm (23 inches) Cairns et al. (2001) • Lake Champlain 12-hr event lead to 33 cm (13 inches) and less than ¼ mile visibilityTardy (2000) • Are there differences between small- and large-lake lake-effect processes or the parameter space of necessary conditions? Does scale matter? • Do lake-effect events over small lakes have different challenges in predictability when compared to large lake events? • Small lake environment likely more sensitive to climate variations than large lake systems (mesoscale - climate connection)
Comparing Lake Spatial Scales – Idealized Model Simulations Lake Area = 31, 416 km2 Lake Area = 7,854 km2 Quasi-steady state circulation after 36 hour simulations U = 12.5 m s-1; DT = 22.5°C; dq /dZ = 1.0 K km-1 below 1.5 km Laird, Kristovich and Walsh (2003)
Past Lake-Effect Studies of Small Lakes Tardy, 2000: Lake effect and lake enhanced snow in the Champlain Valley of Vermont. NWS/NOAA technical attachment (NO. 2000-05). 27 pp. Watson et al., 1998: High resolution numerical simulations of Finger Lakes snow bands. Preprints, 16th Conf. on Wea. Anal. and Forecasting Cosgrove et al., 1996: Lake effect snow in the Finger Lakes region. Preprints, 15th Conf. on Wea. Anal. and Forecasting. Carpenter, D.M., 1993: The Lake Effect of the Great Salt Lake: Overview and Forecast Problems. Wea. Forecasting, 8, 181–193. Steenburgh et al., 2000: Climatology of lake-effect snowstorms of the Great Salt Lake. Mon. Wea. Rev., 128, 709–727. Steenburgh and Onton, 2001: Multiscale Analysis of the 7 December 1998 Great Salt Lake–Effect Snowstorm. Mon. Wea. Rev., 129, 1296–1317. Onton and Steenburgh, 2001: Diagnostic and Sensitivity Studies of the 7 December 1998 Great Salt Lake–Effect Snowstorm. Mon. Wea. Rev., 129, 1318–1338. Wilken, 1997: A lake-effect snow in Arkansas. NWS/NOAA technical attachment (SR/SSD 97-21). 3 pp. Schultz et al., 2004: Snowbands during the cold-air outbreak of 23 January 2003. Mon. Wea. Rev., 132, 827-842. Huggins et al., 2001: A lake effect snowfall in Western Nevada - Part II: Radar Characteristics and quantitative precipitation estimates. Preprints, 18th Conf. on Weather Analysis and Forecasting/14th Conf. on Numerical Weather Prediction. Sikora and Halverson, 2002: Multiyear observations of cloud lines associated with the Chesapeake and Delaware Bays. J. Appl. Meteor., 41, 825-831.
Comparing Lake Spatial Scales Lake Ontario (18,960 km2) Great Salt Lake (4,400 km2) Lake Champlain (1,127 km2) Lake Tahoe (490 km2) Seneca Lake (175 km2)
Lake Champlain & New York State Finger Lakes Lake Champlain Eastern Lake Ontario Eastern NYS Finger Lakes satellite map courtesy of Google Maps
(a) 1347 UTC 08 Mar 1996 (b) 0605 UTC 09 Mar 2005 (c) 1203 UTC 03 Dec 2003 Lake-Effect Event Types – NYS Finger Lakes & Lake Champlain SYNOP LOenh NYSFL SYNOP LC LC-South Lake Champlain NYS Finger Lakes
N of NYS Finger Lakes N of Champlain Lake-Effect Frequency – Lake Champlain & NYS Finger Lakes NYS Finger Lakes Lake Champlain (11 winters) (9 winters) 3.9 2.9 2.7 1.9 2.0 1.5 1.3 1.0 0.9 Laird, Desrochers and Payer (2009) Laird, Sobash and Hodas (2009)
Start Time Event Duration 75% End Time 90% Lake-Effect Event Duration & Timing NYS Finger LakesLake Champlain Duration Start Time End Time 75% Mean: 9.4 hrs Mean: 12.1 hrs
Lake-Effect Event – Finger Lakes – SLP composites H NYSFL LOenh SYNOP L L L H H
Lake-Effect Event – Lake Champlain – SLP composites H L L H L H
CHYU Lake Champlain & New York State Finger Lakes PLB VMCR BTV Lake Champlain Eastern Lake Ontario ROC SYR Eastern NYS Finger Lakes PEO ITH satellite map courtesy of Google Maps
Surface Temperatures (based on hourly observations during events) NYS Finger LakesLake Champlain
Lake – Air Temperature Difference NYS Finger LakesLake Champlain
Dew Point Temperature NYS Finger LakesLake Champlain
Sea-Level Pressure NYS Finger LakesLake Champlain
Surface Wind Speed NYS Finger LakesLake Champlain
(a) 1347 UTC 08 Mar 1996 (b) 0605 UTC 09 Mar 2005 (c) 1203 UTC 03 Dec 2003 Finger Lakes Lake-Effect: Depth of Stable Layer SYNOP LOenh NYSFL
Finger Lakes Lake-Effect North South
Great Salt Lake, Lake Tahoe, & Pyramid Lake Great Salt Lake Pyramid Lake Lake Tahoe satellite map courtesy of Google Maps
N of NYS Finger Lakes N of Champlain Lake-Effect Frequency: Small Lakes vs. Large Lake Finger LakesLake Champlain N of Ontario 80 60 40 20 0 Lake Ontario Tahoe / Pyramid
Summary • Lake-effect occurs on NYS Finger Lakes with an average of 11 events per winter • Lake Champlain - 7 events per winter • Lake Tahoe / Pyramid Lake - 4 events per winter • Although NYS Finger Lakes are smaller than Lake Champlain, favorable lake-effect forcing conditions are more easily reached more events • Attribute to Lake Ontario being upstream providing source of heat, moisture and pre-existing lake-effect circulations • Lake-effect type and associated conditions linked to evolutional stage of synoptic pattern and southward establishment of polar air mass • SYNOP LOenh NYSFL(NYS Finger Lakes) • SYNOP LC-North LC-South(Lake Champlain) • Narrow set of conditions necessary for lake-effect on small lakesOpen question: How do these compare to Great Lakes lake-effect conditions?Open question: What is the predictability of small lake LE events? Null cases? • Link between mesoscale events and regional climate variabilityOpen question: Given the narrow set of conditions for lake-effect on small lakes, can the frequency and variability of these events be an indicator for changes in climate or demonstrate what might happen with regional climate changes?