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Thank you, I have already converted my temperature and dewpoint to Celsius from Kelvin if that is what you mean by "required units". I understand now after doing some more looking that the equation I provided was the same e/esat*100 equation you were talking about except I derived vapor pr...

Hello, I am trying to use measurements of humidity as control variables in a model of pollution. Currently I am using the QLML surface specific humidity measure from Surface Flux Diagnostics. I understand that this represents the ratio of the mass of water vapour in the air relative to the mass of t...

Hello, I am looking to use the monthly average of Total Precipitation (PRECTOT) from M2TMNXFLX. The current data is presented kg m^-2 s^-1 and I am wondering what the formula is for converting to other measurements of rainfall such as mm/hour or mm/day. From searching online I saw suggestions of mul...

Hello, I have been looping code to generate URLs and subsequently download MERRA2 data. I have noticed that for a number of months in the monthly data the URL is slightly different. For example MERRA2_400.tavgM_2d_flx_Nx.202008.nc4 for August 2020 MERRA2_401.tavgM_2d_flx_Nx.202009.nc4 for September ...

Hello, Manually downloading MERRA 2 files from GES DISC I appear to have identified the issue. The URL changes between decades with post 2011 files having MERRA2_400 while the 2000s uses MERRA2_300 and I believe the 1990s uses MERRA2_200 and 1980s uses MERRA2_100. Changing that in my URL generation ...

Hello, I am attempting to download a number of variables from the MERRA-2 dataset. I am using R to download using GET as I have done before however for some reason I cannot download data before January 2011. Doing so yields a status code 404. Even manually putting the URL into my web browser yields ...

Thank you very much for your answer and clarification. I am wondering where this is stated or is the usage of height above ground level implicit in the calculation of PBLH?

Apologies I should have specified I was looking at the MERRA-2 dataset. Looking at the paper you provided it seems to use geopotential height which is based on sea level.

I am currently looking at the height of the Planetary Boundary Layer in order to study its impact on pollution. I am just wondering whether the height in meters is relative to sea level or to the first observed layer? I have searched through documentation but cannot find an answer. This is important...

Hello. I apologise if this is a simple question but I am wondering whether the coordinates in MERRA-2 correspond to the centre of the 0.625° x 0.5°grid? Is there anywhere in the documentation where this is explicitly stated?