I was looknig at the gravitational data provided in JGMRO_110C_SHA.TAB and I could not understand how to use the uncertainties provided.
I see that for example the third column of the first line provides a value of 1.9E-05 and the description of this number is "For a gravity field model the uncertainty in the gravitational constant GM in kilometers cubed per seconds squared for the planet"
I wanted to generate a "perturbed" gravity field based on this uncertainty. How would you recommend to do it? Shall I assume a uniform distribution and compute the
Real_GM = Nominal_GM + uniform(-1,1)*uncertainty
Or do you recomend using a gaussian distribution using the uncertainty as 1-sigma value?
In a similar way, the file also provides uncertainties for the coefficients Cmn and Smn.
How shall understand this uncertainties if I want to create a perturbed (non-nominal) gravity field using all the coefficients and uncertainties provided in the file? Should I use a similar formulation of the one presented above?
Use of uncertainties in gravity model
in For data users
Posted
Good morning
I was looknig at the gravitational data provided in JGMRO_110C_SHA.TAB and I could not understand how to use the uncertainties provided.
I see that for example the third column of the first line provides a value of 1.9E-05 and the description of this number is "For a gravity field model the uncertainty in the gravitational constant GM in kilometers cubed per seconds squared for the planet"
I wanted to generate a "perturbed" gravity field based on this uncertainty. How would you recommend to do it? Shall I assume a uniform distribution and compute the
Real_GM = Nominal_GM + uniform(-1,1)*uncertainty
Or do you recomend using a gaussian distribution using the uncertainty as 1-sigma value?
In a similar way, the file also provides uncertainties for the coefficients Cmn and Smn.
How shall understand this uncertainties if I want to create a perturbed (non-nominal) gravity field using all the coefficients and uncertainties provided in the file? Should I use a similar formulation of the one presented above?
Many thanks in advance
Kind regards,
Alvaro