frank0434 / Master

repo for the master project - water stress for APSIMX lucerne model
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parameter optimisaion via factorial #22

Open frank0434 opened 3 years ago

frank0434 commented 3 years ago
frank0434 commented 3 years ago

image

frank0434 commented 3 years ago

Actual soil evaporation is equal to potential evaporation up to a specified limit u (stage I) after which the evaporation rate becomes proportional to the square root of time (stage II):

*$cumulative_second_stage = cona t^0.5$**

Methodology in soil-water-solute balance modelling: An evaluation of the APSIM-SoilWat and SWIMv2 models

frank0434 commented 3 years ago

A conservative estimate of 2 is recommended for U as a modelling parameter. This is lower than most values commonly in use (3-8), however in agreement with recommendations from Yunusa et al. (1994) for Australian conditions.

ConA - winter: 3.0(±1.3) to 3.7(±1.4) ConA - summer: 4.6(±0.4) to 5.3(±0.4)

SOIL EVAPORATION – HOW MUCH WATER IS LOST FROM NORTHERN CROP SYSTEMS AND DO AGRONOMIC MODELS ACCURATELY REPRESENT THIS LOSS?

frank0434 commented 3 years ago

In New Zealand U and α are soil texture properties of 9 mm and 4.4 mm/day-1/2 reported for a silt loam soil (Jamieson et al., 1995a), similar

ES occurred when the SWC content of the top layer was greater than the lower limit. from Richard's thesis

frank0434 commented 3 years ago

How to calculate Evaporation? water balance? ConA must be smaller than U? No ConA is in charge of the 2nd stage. U is the amount of water control when to go to the 2nd stage.

Solutions - CompositeFactor? image

How can I check if the simulation use the correct values? report only show the name of the value, not the exact values

frank0434 commented 3 years ago

2430 simulations if using a setup like the snapshot Simulations complete [824.97 sec]

frank0434 commented 3 years ago

[Soil].SoilWater.SummerU = 1 to 9 step 1 [Soil].SoilWater.SummerCona = 1 to 6 step 0.5

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Seems we can remove the combination below simulation ID 2000

Remove 2000 image

Seems ok to remove 3000

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U ranges from 1 to 9 ConA ranges from 4 to 6 This reduced the number of simulations down to 2430 from 5346

The mismatch in the red circle could be caused by Winter u and cona what is the definition of summer and winter here? Answers:

 [Description("Start date for switch to winter parameters for soil water evaporation")]
        public string WinterDate { get; set; } = "1-Apr";
[Description("Start date for switch to summer parameters for soil water evaporation")]
        public string SummerDate { get; set; } = "1-Nov";
frank0434 commented 3 years ago

with an arbitrary combination parameters: U = 4 Cona = 4 Gsmax = 0.006 and the 54 KLR with RFV and 0.06 SKL image image

frank0434 commented 3 years ago

with an arbitrary combination parameters: U = 4 Cona = 4 Gsmax = 0.006 winterU = 1, 10 wintercona = 9, 0 and the 54 KLR with RFV and 0.06 SKL

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lower the U and cona during winter definitely improve that funny bit in the red circle. but guess the definition of summer of winter need to be tested as well?

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change the summer definition from 1-Nov to 1-Sep

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