SEACOOS CDL v2.0 December 9, 2004 14 water_v:standard_name = "northward_current" ; water_v:units = "cm s-1" ; water_v:z = -5. ; If a vertical current component is measured then this can be provided with an upward current component variable (water_w). float water_w(time) ; water_w:standard_name = "upward_current" ; water_w:units = "m s-1" ; water_w:z = -5. ; 8. Filename The file name extension of each netCDF file should be .nc. To promote easy real-time aggregation, netCDF files with real-time observations should have latest as part of the filename proceeding the suffix .nc. The most general filename form is latest.nc.   In addition, while it is not mandatory, it is recommended that a partner acronym, platform identification, and instrument package type be added to the filename to distinguish the source of the data by virtue of just a directory listing. The general form that is recommended is partner- platform-package-latest.nc. For example, the most recent 48 hours of data from University of South Florida meteorological buoy (CMP4) at Pasco County, Florida, should be stored in the netCDF file named usf-CMP4-met-latest.nc. 9. Global Attributes In this section the required and recommended global attributes are described. An example entry is provided for each description. These attributes provide information about where the data came from and what has been done to them. Whenever an attribute is present as both a global and variable attribute, the variable attribute takes precedence. The CDL notation for defining a global attribute is :attribute_name = list_of_values; 9.1 Required Global Attributes The following required global attributes must be present in each netCDF file.  If an attribute does not have a value, still include it in the file but with some “not applicable” statement.      :title   Text. A succinct description for what is in the file.   Example: "SABSOON data for US Navy Tower R2" :institution   Text. The name of the institution responsible for creating the file.