giulange / get_modis

Downloading MODIS data from the USGS repository

get_modis

Info:	MODIS data product granule downloader
Author:	J Gomez-Dans <[email protected]>
Date:	2013-06-17
Description:	README file

Description

This repository contains a Python script (and executable) that allows one to download MODIS data granules for different products and periods.

The code is quite simple and generic, and should work with most standard Python installations.

See more here.

Usage

This is a command line tool. It has only been tested on Linux, but should also work with Windows. There are a number of options that can be used, and you can get a list of them issuing the -h or --help commands. Also note that as of summery 2016, you must have a username and password pair to access the server. If you haven't got one, you can get it here. You will also need to allow your user account to access the USGS MODIS archive (you only need to do this once).

Useful things to bear in mind:

• The platform MUST be one of MOLA (Aqua), MOLT (Terra) or MOTA (Combined).
• The product must have an indication of the collection follwing the product name. i.e. MCD45A1.005)
• The --begin and --end flags are optional, and yu can ignore them if you just want the complete year
• Use the --proxy option to set the required proxy. It should be read from the environment variable, but this is added flexiblity

The code has some logic not to download files several times, and the overall behaviour rests on the --quick flag: if this flag is not set, then the program will look at the remote available files and skip any files that are present and have the same file size as the remote. In some cases, this could lead to duplicities are re-processing takes place. If the --quick flag is set, then when the remote list of available dates is created, any present files that match the requested product and year will be ignored, irrespective of file size. This can mean that files that failed to download half way through will not the downloaded, but it's an overall faster process if a download failed halfway through a year.