Simulated One Point Mode

Simulated One Point Mode

This mode is only verified for Mars but is now supported for other bodies.

It requires:

1: a Temperature T

2: @ a season ls

3: @ a LTST hour

 OUT = krc(lat=12.,lon=12.,T=190.,ls=0.,hour=4.)

The output is the equivalent thermal inertia in J m-2 K-1 s-1/2, in this case OUT = 334 Jm-2K-1s-1/2.

The One-Point Mode outputs a TI (SI) for an array of input temperatures with the given parameters

If no solution can be found, it can output various values that indicate why a TI was not derived for failure cases:

-500: No value was derived or returned. KRC might have failed to run all together

-400: TI value lower than look up table (~15 SI), possibly negative (non-sensical)

-300: TI value higher than look up table (~2200 SI) and extrapolation is not permitted

-200: Returned TI value doesn't meet proximity criterion (TI_Guess_PCT)

-100: Bad TI_Guess / TI_Guess_PCT combination. This is most likely a user error

Flags are only provided as a potential help for the user. Do not solely rely on them to diagnose an unexpected output.

To speed up the processing time, the user can provide a TI guess (TI_Guess), and an acceptable tolerance.

Below, the user provides a good guess (300 Jm-2K-1s-1/2 vs. 334 Jm-2K-1s-1/2). The processing time is significantly reduced.

OUT = krc(T=190,ls=0.,hour=4.,lat=12.,lon=12.,TI_Guess=300.)

If the user provides a poor guess, the output may be OK, but sometimes it will be wrong. For example:

OUT = krc(T=190,ls=0.,hour=4.,lat=12.,lon=12.,TI_Guess=600.)

...still yields an OK result.

OUT = krc(T=190,ls=0.,hour=4.,lat=12.,lon=12.,TI_Guess=900.)

...is too far off, and a flag comes out (-400, TI too low, possibly <0).

To avoid this situation, set a tolerance (TI_Guess_PCT), in % of the guess within which the solution is deemed acceptable. Here the initial guess is within 20% of the solution, so KRC returns a value (334 Jm-2K-1s-1/2).

OUT = krc(T=190,ls=0.,hour=4.,lat=12.,lon=12.,TI_Guess=300.,TI_Guess_PCT=0.2)

If the tolerance criterion is not met, a flag is retuned (-200). Here the solution is not within 5% of the guess.

OUT = krc(T=190,ls=0.,hour=4.,lat=12.,lon=12.,TI_Guess=300.,TI_Guess_PCT=0.05)

Pathological Case: the user set a tolerance but no guess. always KRC runs, sets TI_Guess to 0., and returns a flag suggesting a user error (-100).

OUT = krc(T=190,ls=0.,hour=4.,lat=12.,lon=12.,TI_Guess_PCT=0.2)

If T is below the frost point, the solution is sometimes a negative TI, and a flag comes up (-400).

OUT = krc(T=130,ls=0.,hour=4.,lat=12.,lon=12.)

If T is below the frost point, and a bad guess is provided, an ambiguous flag can come up (-400).

OUT = krc(T=130,ls=0.,hour=4.,lat=12.,lon=12.,TI_Guess=200.) 

If T is below the frost point, and a poor guess is provided, the poor tolerance flag comes up (-200).    

OUT = krc(T=130,ls=0.,hour=4.,lat=12.,lon=12.,TI_Guess=200.,TI_Guess_PCT=0.5)

 

If T is too high, a high TI flag comes up (-300.), most likely for night data.                                                           

OUT = krc(T=500,ls=0.,hour=4.,lat=12.,lon=12.)

If T is too high, and poor guess is provided, a high TI flag comes up (-300.).

OUT = krc(T=500,ls=0.,hour=4.,lat=12.,lon=12.,TI_Guess=200.)

If T is too high, and poor guess is provided, with a low tolerance (violated), the poor tolerance flag comes up (-200).

OUT = krc(T=500,ls=0.,hour=4.,lat=12.,lon=12.,TI_Guess=200.,TI_Guess_PCT=0.1)