The LSM error model provides sampling accuracy, error biases and representativeness errors
depending upon which horizontal wind model (High Resolution model, Grid Area - MPA,
Grid Area - Least Squares) is used. Each error type is identified with indicators
for error, data level, error type and error attribute. ERROR DEFINITION The data level corresponds to a specific LSM Level product. The error levels are defined
as follows... DATA LEVEL 00 - error with respect to analog/digitization 01 - error with respect to Line of sight velocities 2A - error with respect to Grid area winds 2B - error with respect to High Resolution winds 03 - error with respect to Model/other assisted winds. ERROR TYPE 0 - estimation with respect to the actual winds at the shot locations 1 - estimation with respect to the actual winds as the assigned location 2 - estimation with respect to the subgrid averaged winds. ERROR ATTRIBUTE E - actual average error R - weighted root mean square error or goodness of fit B - weighted bias. For example, take E 2B 0 E, where E - error indicator 2B - data level 0 - data level E - error attribute HORIZONTAL WIND MODEL ERRORS High Resolution mode E2BOE = Ve(m)i - Va(a:f)i E2BOB = E2BOE E2BOR = 0.0 E2B1E = Ve(m)i - Va(m)i
E2B1B = E2B1E
E2B1R = 0
Grid Area Resolution mode (MPA)
E2AOE = ( SiN (Ve(m)i × wf(i)) / SiNwf(i) ) - ( SiNVa(a:f)i ) / N
E2AOB = ( SiN (Ve(m)i - Va(a:f)i) × wf(i) ) / SiN wf(i)
E2AOR = Ö(( SiN (Ve(m)i - Va(a:f)i)2 × wf(i) ) / SiN wf(i) )
E2A1E = ( SiN Ve(m)i × wf(i) ) / SiN wf(i) - ( SiN Va(m)i ) / N
E2A1B = ( SiN (Ve(m)i - Va(m)i) × wf(i) ) / SiN wf(i)
E2A1R = Ö (( SiN (Ve(m)i - Va(m)i)2 × wf(i) ) / SiN wf(i) )
E2A2E = ( SiN Ve(m)i × wf(i) ) / SiN wf(i) - Vg
E2A2B = ( SiN (Ve(m)i - Vg) × wf(i) ) / SiN wf(i)
E2A2R = Ö (( SiN (Ve(m)i - Vg)2 × wf(i) ) / SiN wf(i) )
Grid Area Resolution mode (Least Squares)
E2A0E = VeLS - SiN Va(a:f)i/N
E2AOR = X2
E2A2E = VeLS - Vg
where
N - represents the number of shots
Va(a:f)i - represents the average error of the actual winds at the for the i'th pair
Ve(m)i - represents the estimated velocity at the weighted measurement location for the i'th pair
Va(m)i - represents the actual wind velocity at the weighted measurement location for the i'th pair
Vg - represents the average of all winds within the global grid domain
VeLS - represents the least squares velocity
| This page managed by Sidney A. Wood | Last modified: 21 Feb. 1998 |