Search found 10 matches

by mbosilov
Mon May 20, 2024 10:27 am America/New_York
Forum: Home
Question: 2-meter temperatures in MERRA-2 derivation
Replies: 2

Re: 2-meter temperatures in MERRA-2 derivation

The 2m data is computed from a Monin-Obukov type surface layer parameterization. See Molod et al. (2015) for some description and references to the derivations, linked from the MERRA-2 documentation pages.
https://gmao.gsfc.nasa.gov/reanalysis/MERRA-2/docs/
by mbosilov
Fri Apr 05, 2024 2:04 pm America/New_York
Forum: Home
Question: unit conversion of MERRA2 variabless
Replies: 2

Re: unit conversion of MERRA2 variabless

As the variable name states, this is a concentration, not a flux or tendency. If you need the total time rate of change you can take the difference of the concentration at two points in time, then divide by the amount of time between the two points.
by mbosilov
Tue Mar 12, 2024 2:37 pm America/New_York
Forum: Home
Question: PM 2.5 unit conversion from kg/m3 to kg/m2
Replies: 4

Re: PM 2.5 unit conversion from kg/m3 to kg/m2

I have data from merra 2 for sea salt mass concentration, the unit is kg/m3 , i need it in kg/m2 for my application. I like value for length scale which needs to multipled to it. How to find a length scale for specific location. Hi, I am assuming that you are using a variable SSSMASS25. The surface...
by mbosilov
Tue Mar 12, 2024 2:33 pm America/New_York
Forum: Home
Question: PM 2.5 unit conversion from kg/m3 to kg/m2
Replies: 4

Re: PM 2.5 unit conversion from kg/m3 to kg/m2

dinesh_5497 wrote: Sat Mar 09, 2024 10:55 am America/New_York I have data from merra 2 for sea salt mass concentration, the unit is kg/m3 , i need it in kg/m2 for my application. I like value for length scale which needs to multipled to it. How to find a length scale for specific location.
by mbosilov
Mon Dec 11, 2023 10:04 am America/New_York
Forum: Home
Question: Merra2
Replies: 4

Re: Merra2

If you read that carefully, you'll see that 60m is an approximate value. This is because the model uses a terrain following coordinate so that the thickness of the layers is a function of pressure. The variable HLML varies in latitude, longitude and time (space and time). This is why we provide the ...
by mbosilov
Fri Dec 08, 2023 8:42 am America/New_York
Forum: Home
Question: Merra2
Replies: 4

Re: Merra2

Well, I'm not a chemistry expert either, but I learned unit conversions quite some time ago. Kg to mg, assuming that the constituent is the same in the conversion, then should just be a multiple of 10. I don't know how many powers of ten to tell you because its not clear if you want, milligram or mi...
by mbosilov
Fri Oct 27, 2023 1:33 pm America/New_York
Forum: Home
Question: Atmospheric enthalpy flux
Replies: 4

Re: Atmospheric enthalpy flux

Take a look at this paper, it has a complete total energy budget discussion, with equations and also variable names in the appendix. The paper is MERRA, but most of that still holds for what is included in MERRA-2.
by mbosilov
Thu Sep 10, 2020 8:06 am America/New_York
Forum: Home
Question: Weather data
Replies: 4

Re: Weather data

Hi, and thanks for your interest in MERRA-2 If you are not familiar with reanalyses methodology, please refer to our documentation and papers here: https://gmao.gsfc.nasa.gov/reanalysis/MERRA-2/docs/ In particular, while observations are used to guide the system, the reason we have data every where ...
by mbosilov
Mon Jun 15, 2020 4:36 pm America/New_York
Forum: Home
Question: MERRA-2 model vertical grid
Replies: 1

Re: MERRA-2 model vertical grid

please email merra-questions@lists.nasa.gov and I can reply with the table of Ak/Bk coefficients.
by mbosilov
Thu Apr 16, 2020 9:15 am America/New_York
Forum: Home
Question: MERRA-2 wind speed data
Replies: 4

Re: MERRA-2 wind speed data

Hi, Just to be sure you have the appropriate information, MERRA-2 Documentation is at: https://gmao.gsfc.nasa.gov/reanalysis/MERRA-2/docs/. Also, be aware that the GMAO maintains a help email for science and technical questions regarding the MERRA-2 data. merra-questions@lists.nasa.gov 1 The pressur...