add two new vars for GLDAS

[jordansread]

psurf is atm pressure (Pa) swnet_tavg is short wave radiation

Blocked by https://github.com/USGS-CIDA/stream_metab_usa/issues/84, so we want to make sure that works before putting in the effort here

[aappling-usgs]

i think swnet_tavg has become swdown, is that right, @jread-usgs ? and would you consider this the best link to include in the metadata: http://hydro1.sci.gsfc.nasa.gov/dods/GLDAS_NOAH025SUBP_3H.info?

[aappling-usgs]

and this one for NLDAS? http://hydro1.sci.gsfc.nasa.gov/dods/NLDAS_FORA0125_H.002.info

[jordansread]

yes for GLDAS. It is swdown and that is the right link. Link for NLDAS is good too

[aappling-usgs]

ok, great.

> mda.streams::get_var_src_codes(var %in% c('sw','baro'), src %in% c('nldas','gldas'))
   var   src  units                     var_descrip data_type metab_var priority
1 baro nldas     Pa             barometric pressure        ts      <NA>        2
2 baro gldas     Pa             barometric pressure        ts      <NA>        3
3   sw nldas W m^-2 downwelling shortwave radiation        ts      <NA>        1
4   sw gldas W m^-2 downwelling shortwave radiation        ts      <NA>        2
                                                             url
1 http://hydro1.sci.gsfc.nasa.gov/dods/NLDAS_FORA0125_H.002.info
2 http://hydro1.sci.gsfc.nasa.gov/dods/GLDAS_NOAH025SUBP_3H.info
3 http://hydro1.sci.gsfc.nasa.gov/dods/NLDAS_FORA0125_H.002.info
4 http://hydro1.sci.gsfc.nasa.gov/dods/GLDAS_NOAH025SUBP_3H.info
                     src_descrip r_package r_function src_type     p_code    var_src
1 Land Data Assimilation Systems  geoknife   geoknife     data    pressfc baro_nldas
2 Land Data Assimilation Systems  geoknife   geoknife     data      psurf baro_gldas
3 Land Data Assimilation Systems  geoknife   geoknife     data   dswrfsfc   sw_nldas
4 Land Data Assimilation Systems  geoknife   geoknife     data swnet_tavg   sw_gldas

[aappling-usgs]

whoops! didn't change swnet_tavg to swdown 3 weeks ago. I think the p_codes are all correct now:

> mda.streams::get_var_src_codes(var %in% c('sw','baro'), src %in% c('nldas','gldas'))
   var   src  units                     var_descrip data_type metab_var priority
1 baro nldas     Pa             barometric pressure        ts      <NA>        2
2 baro gldas     Pa             barometric pressure        ts      <NA>        3
3   sw nldas W m^-2 downwelling shortwave radiation        ts      <NA>        1
4   sw gldas W m^-2 downwelling shortwave radiation        ts      <NA>        2
                                                             url
1 http://hydro1.sci.gsfc.nasa.gov/dods/NLDAS_FORA0125_H.002.info
2 http://hydro1.sci.gsfc.nasa.gov/dods/GLDAS_NOAH025SUBP_3H.info
3 http://hydro1.sci.gsfc.nasa.gov/dods/NLDAS_FORA0125_H.002.info
4 http://hydro1.sci.gsfc.nasa.gov/dods/GLDAS_NOAH025SUBP_3H.info
                     src_descrip r_package r_function src_type   p_code    var_src
1 Land Data Assimilation Systems  geoknife   geoknife     data  pressfc baro_nldas
2 Land Data Assimilation Systems  geoknife   geoknife     data    psurf baro_gldas
3 Land Data Assimilation Systems  geoknife   geoknife     data dswrfsfc   sw_nldas
4 Land Data Assimilation Systems  geoknife   geoknife     data   swdown   sw_gldas