GLEON Physics/Climate Update

• Jordan Read, Kohji Muraoka, David Hamilton, Evelyn Gaiser, Ian Jones etc

Plan

• Collect water temperature (full depth) and wind data (preferably hourly)

• Automate calculation of stability parameters (Schmidt Stability, Wedderburn Number, Lake Number) – a number of steps required in this

• Analyse for a plethora of questions on stability and episodic events (detection and severity, controls, frequency, timescales….)

Data set

• 15 lakes

• Other lakes available

• Denmark, Germany, Ireland, New Zealand, United Kingdom, US of A

• 0.09 – 600 km2

• 5 – 253 m depth

• Different dates from ‘05 – ’09 (approx 1 yr)

Date Time temp0 Temp1.0 temp2.0 temp3.5 temp5.0 Temp7.0 Temp9.0 temp11.0

7/5/2007 18:00 23.84 23.68 23.46 23.1 23.04 22.89 22.72 22.35

7/5/2007 19:00 23.9 23.685 23.465 23.32 23.1275 22.88 22.73 22.3975

7/5/2007 20:00 23.9733 23.7975 23.732 23.46 23.2825 22.9467 22.78 22.42

7/5/2007 21:00 23.898 23.79 23.7567 23.415 23.314 22.892 22.7333 22.35

7/5/2007 22:00 23.738 23.73 23.6967 23.41 23.21 22.855 22.72 22.398

7/5/2007 23:00 23.65 23.68 23.6167 23.406 23.1525 22.865 22.72 22.325

7/5/2007 24:00 23.535 23.61 23.698 23.35 23.18 22.85 22.6967 22.252

7/6/2007 1:00 23.465 23.545 23.655 23.4 23.17 22.85 22.712 22.3575

7/6/2007 2:00 23.39 23.492 23.59 23.465 23.2775 22.8525 22.716 22.4

°C

Temp2Density

(Hours assumed to be void of surface heat)NightTimeHours = [23 24 1 2 3 4 5 6 7 8 9]

splineFit findThermoCl

Max d/dz

The

rmoc

line

dept

h (m

)

time

findOutliers

NightTimeHours

The

rmoc

line

dept

h (m

)

Replace with running ave

Full thermocline time series

if d/dz < slopeCriteriabreak

Themocline estimate

metaTopSearch

metaBotSearch

Met

alim

nion

dep

th (

m)

time

findOutliers

Met

alim

nion

dep

th (

m)

Replace with running ave

Met

alim

nion

dep

th (

m)

Calc 6hr running ave

Lake Taupo

Lake Annie

Lake Castle