Recipe: Retrieve (global) data from FTP server

Problem

We want to access G5NR data by downloading files by ftp/wget.

Solution

The base url for G5NR data is ftp://G5NR@:ftp.nccs.nasa.gov/c1440_NR/DATA.

At this location, the data is organized by resolution (0.5000_deg/0.0625_deg), type (const/inst/tavg/tdav), collection name, year, month and day as follows:

|-- resolution
|   |-- type
|   |   |-- collection
|   |   |   |-- year
|   |   |   |   |-- month
|   |   |   |   |   |-- day

[some details on what the types are etc.]

A web browser can be used to browse directories, read and retrieve files. To retrieve the collection inst01hr_3d_T_Cv for the day 2006-09-18, one needs to point to: ftp://G5NR:@ftp.nccs.nasa.gov/c1440_NR/DATA/0.5000_deg/inst/inst01hr_3d_T_Cv/Y2006/M09/D18. Alternately, one can use the command line tool wget to retrieve the same files as: wget ftp://G5NR:@ftp.nccs.nasa.gov/c1440_NR/DATA/0.5000_deg/inst/inst01hr_3d_T_Cv/Y2006/M09/D18/* The * at the end would retrieve all (24) files for the given day. To download a file for a specific time, say 0900z, try wget ftp://G5NR:@ftp.nccs.nasa.gov/c1440_NR/DATA/0.5000_deg/inst/inst01hr_3d_T_Cv/Y2006/M09/D18/c1440_NR.inst01hr_3d_