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MeteoNet's toolbox and documentation
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Questions about Radar data in MeteoNet. #19

Open zhangfuhan opened 3 years ago

zhangfuhan commented 3 years ago

We wanted to ask a question in Slack Workspace “https://tinyurl.com/meteonet-slack”, but it couldn't be accessed.

https://meteofrance.github.io/meteonet/english/data/rain-radar/

We want to ask what is the height of the radar data in the old product. Is it radar echo data representing a fixed altitude? For example, 850hPa and 600hPa. Or is it an accumulation of radar echo data from multiple altitudes?

Looking forward to your reply!

larvorg commented 3 years ago

Hello, sorry for the answer delay, I did not see your issue.

the invitation link has been updated here is the new : https://tinyurl.com/meteonet-slack0421

The height is about the selected radar measure height (in meters). So it is not about radar echo data, but only the measure height.

I have no other information today, but let me search to know more on what does mean that parameter.

larvorg commented 3 years ago

Hello, I had more information. It is about the height against the radar beam. It can be used to estimate the quality of reflectivity estimation close to ground. A high height value can be caused for several reasons. For example, the measure is not come from a height close to ground (because we have water drops high in altitude, so the reflectivity is maximum in altitude). Other example, we do not have measure close to ground with a sufficient quality (so we under-estimate the reflectivities close to ground).

I hope it is clearest now.