Robert Edmonds
EF5
Hi all,
While it is usually for stated for nexrad that the velocity error is ~m/s for a spectrum width of 4m/s (correct me if I'm wrong), I've been trying to figure out how to actually determine what the errors for the radar are, especially when it comes to the velocity information.
While doing some digging to try and come up with an answer I found this plot from the Federal Meteorological Handbook.
While this plot is helpful, I've been trying to determine what this plot would look like for different actual velocities(Va on the plot). For instance how does this plot scale or look with a actual velocity of a few m/s or for say 50 m/s. There are some sources listed in the handbook but the few I could find made me a little lost. Also, I have a feeling this plot looks allot different if you take into account that your measurement of the width has an error too.
Also, a m/s for a width of 4m/s is quoted but it seems some from what I've gathered tend to think the error is larger, and that 2-3 m/s error for velocity measurements might more appropriately account for the error...
Some researchers seem to circumvent this and take an rms of the velocity field but I'm trying to avoid doing this.
All in all, I'm basically asking how can the error for a velocity measurement be determined? Is there an equation which is typically involved taking into account width and/or signal strength and/or any other necessary variables? Even if the functions are a minimum or maximum error estimate, this would be great of you to share too.
Any help would be greatly appreciated...
While it is usually for stated for nexrad that the velocity error is ~m/s for a spectrum width of 4m/s (correct me if I'm wrong), I've been trying to figure out how to actually determine what the errors for the radar are, especially when it comes to the velocity information.
While doing some digging to try and come up with an answer I found this plot from the Federal Meteorological Handbook.
While this plot is helpful, I've been trying to determine what this plot would look like for different actual velocities(Va on the plot). For instance how does this plot scale or look with a actual velocity of a few m/s or for say 50 m/s. There are some sources listed in the handbook but the few I could find made me a little lost. Also, I have a feeling this plot looks allot different if you take into account that your measurement of the width has an error too.
Also, a m/s for a width of 4m/s is quoted but it seems some from what I've gathered tend to think the error is larger, and that 2-3 m/s error for velocity measurements might more appropriately account for the error...
Some researchers seem to circumvent this and take an rms of the velocity field but I'm trying to avoid doing this.
All in all, I'm basically asking how can the error for a velocity measurement be determined? Is there an equation which is typically involved taking into account width and/or signal strength and/or any other necessary variables? Even if the functions are a minimum or maximum error estimate, this would be great of you to share too.
Any help would be greatly appreciated...
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