Recipe: Retrieve (global) data from FTP server

Back to G5NR Data Access Guide.

Problem

We want to access G5NR data by downloading files from the ftp server using either a web browser or the command line tool wget.

Solution

NOTE: If you are bookmarking an ftp location you may need to manually add G5NR@ to the bookmarked url.

The base url for G5NR data is

ftp://G5NR@ftp.nccs.nasa.gov/Ganymed/7km/c1440_NR/

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:

DATA
|   resolution
|   |   type
|   |   |   collection
|   |   |   |   year
|   |   |   |   |   month
|   |   |   |   |   |   day

[some details on what the types are etc.]

Download using a web browser

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/Ganymed/7km/c1440_NR/DATA/0.5000_deg/inst/inst01hr_3d_T_Cv/Y2006/M09/D18.

At this location, a file may be downloaded by simply clicking on the file name.

Download file(s) using the command line tool wget

The command line tool wget can be used to retrieve the same files as

wget ftp://G5NR:@ftp.nccs.nasa.gov/Ganymed/7km/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, we can use

wget ftp://G5NR:@ftp.nccs.nasa.gov/Ganymed/7km/c1440_NR/DATA/0.5000_deg/inst/inst01hr_3d_T_Cv/Y2006/M09/D18/c1440_NR.inst01hr_3d_T_Cv.20060918_0900z.nc4

See Also

1. File Spec: File:G5NR-Ganymed-7km FileSpec-ON6-V1.0.pdf