LowerMysticLake

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Comparision of 5 hypsometric curvesFor Lower Mystic Lake(blue points are average of 3)

Kalff, Ch. 11Highlights

Heat and Stratification

Key ideasThe Heat budget of a lakeDefinitionsThe components of the heat budget: (1-A) Rs +RLd –Rlup-LE-H +Qin-Qout-Qsed+M = rate of change in storageIndividual fluxes:

Shortwave radiation (from last class, mostly)Longwave radiation: Boltzmann eqn, Wein displacement law, emissivityLongwave back radiation: sky, clouds, canopyEvaporative heat fluxSensible HeatIce formation and melting

StratificationDefinitionsLocal stabilityWater column stabilityRelationships with lake morphometry and size

Vertical Mixing and entrainmentQuantitative modelsEmpirical: mass tracer or heat as a tracer

In Eagleson, 1970

Ragotzkie, in Lerman et al. 1979

In: Eagleson, 1970

In: Ragotzkie, 1978

From Kalff, 2002

From Kalff, 2002

From Charu Varadharajan thesis, 2009

Upper Mystic Lake Data, October 1, 1984

Depth Temp deg C DO mg/L Light Intensity (uE/(m2s)0 18.3 9.1 6600.5 5401 18.3 3002 18.2 1053 18.2 96 18.2 8.37 18 7.68 16.5 0.79 17 0.510 14 0.07511 11.712 11.713 10.914 9.815 9.8

Secchi Depth = 2 m

In Ragotzkie, 1978

In Lerman, 1978

In Fischer et al., 1979

In Kalff, 2002

In Fischer et al, 1979

From Kalff, 2002