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Urban-Meteorology-Reading / WRF-SUEWS

WRF-SUEWS coupling project
https://wrf-suews.readthedocs.org
MIT License
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First vertical point in WRF #35

Closed hamidrezaomidvar closed 5 years ago

hamidrezaomidvar commented 5 years ago

@sunt05 : I am a bit confused about the variable we should use for the height of first grid point. There is Z variable in surface_driver, which is explained [here](Which of the following elevation should we use for this: https://www.openwfm.org/wiki/How_to_interpret_WRF_variables#Location) z_at_w is not in surface driver, but it is just staggered version of Z where velocities are stored there. I tried to look at this variables (for the lowest grid), and they change with time, and also for different domains! a little bit confusing. There is another variable which is dz8w which is dz of velocity grids which is seems is around 50m for our setup, and does not change between domains!

sunt05 commented 5 years ago

z_at_w is not in surface driver, but it is just staggered version of Z where velocities are stored there. I tried to look at this variables (for the lowest grid), and they change with time, and also for different domains! a little bit confusing.

z is what we want and it does change over time as WRF uses eta levels following pressures in the vertical discretisation. This is why it is now (when we get other parameters ready) critical for us to get the correct measurement height into SUEWS (i.e., a fixed z_meas is essentially wrong) .

hamidrezaomidvar commented 5 years ago

Ok! That's what I thought. The only confusion I couldn't solve was this fact that it seems Z also changes with domains. For example, for domain 1 and 2, for our setup, Z of lowest level is around 25, but for domain 3 is around 150 (this values also can change between domain significantly, and I am talking about the average of them)

sunt05 commented 5 years ago

Ok! That's what I thought. The only confusion I couldn't solve was this fact that it seems Z also changes with domains. For example, for domain 1 and 2, for our setup, Z of lowest level is around 25, but for domain 3 is around 150 (this values also can change between domain significantly, and I am talking about the average of them)

might be worth checking the associated pressures: if they are consistent between domains, then no worries. e.g., even though the first level is 25 m in d01 but 150 m in d03, as long as the according pressures are consistent (e.g., 100 kPa in d01 and 92 kPa in d03), then they should be fine.