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[LDM #VIU-792449]: How to find incoming direct radiation data

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  • Subject: [LDM #VIU-792449]: How to find incoming direct radiation data
  • Date: Wed, 09 Mar 2016 08:54:45 -0700
> Hello Jeff

Hi Wonsook, 

> 
> Thank you very much for your email. Although there is no incoming direct 
> radiation, I find out that the good news is I can still get what I need from 
> Unidata. The reason I originally asked about incoming direct radiation is to 
> calculate net incoming solar radiation (Rn). But, another way to calculate 
> this Rn is using other four radiation products, i.e. incoming shortwave and 
> longwave radiation at the surface (DSWRF, DLWRF) & outgoing shortwave and 
> longwave radiation at the surface (USWRF, ULWRF). Those were found at
> 
> http://rapidrefresh.noaa.gov/GRIB2Table_GSDrap_2d.txt
> 
> (This is the website you provided!)


Yes, these parameters are generated for the model output, but I am NOT seeing 
them being transmitted. My thought is that they are used for other "derived" 
parameters, such as CAPE and CINS. I "sniffed" the feed of NCEP model output 
and did not find any radiation fields coming over the IDD feed for HRRR, RAP, 
GFS, NAM....

I am contacting NOAA GSD, the folks who developed the HRRR, and will see how we 
get these radiation fields.


> 
> I have more questions. May I?
> 
> 1. Are those data from this website having spatial resolution coarser than 3 
> km, I believe? Is it 13 km? If I am wrong, what is the spatial resolutions of 
> these products? I read about the resolution somewhere, but couldn't find it 
> at Rapid Refresh's homepage at http://rapidrefresh.noaa.gov/. Are these 
> available using NGRID or EXP?
> 

HRRR would be 3km, RAP would be 13km, .25 GFS would be ~28km...

> 2. You mentioned about net shortwave radiation surface (NSWRS). Is that 
> product specified for incoming or outgoing? There is the third way to 
> calculate Rn is using incoming net shortwave radiation at surface and 
> outgoing net longwave radiation at surface. Are you able to find these two as 
> well? If abailable which feed provides these two?
> 

Yes, many ways to get to the desired value, but we need to see what is 
available.


> 3. I  assume that incoming direct radiation (that I originally look for) is 
> same as Rs (incoming total solar radiation). Am I correct? If not, would 
> there still be a possibility of having "incoming total solar radiation" from 
> Unidata? Have you encountered with this term "incoming total solar radiation"?

I ~believe incoming total solar radiation is both short and long wave 
downwelling flux.

> 
> 
> Thank you very much for your help again.

Sorry for the delay, will get back asap regarding how we get the radiation 
fields from the HRRR...



> 
> Best,
> Wonsook
> 


Jeff
Jeff Weber
Unidata User Support
http://www.unidata.ucar.edu

Ticket Details
===================
Ticket ID: VIU-792449
Department: Support IDD
Priority: Normal
Status: Open