Ibrahim N. Mohammed

NASAaccess is a software application in the form of a R package, a conda package, and a Tethys web application. NASAaccess software can generate gridded ascii tables of climate CMIP5, CMIP6, and earth observation remote sensing data (GPM, TRMM, GLDAS) needed to drive various hydrological models (e.g., SWAT, VIC, RHESSys, …etc.). The NASAaccess Tethys web-based application can be used for accessing, reformatting, and visualizing climate and earth observation remote sensing gridded time series data as well.

• R package can be downloaded from GitHub at https://github.com/nasa/NASAaccess.

• Conda package can be installed directly from Anaconda by searching for r-nasaaccess.

• Tethys web-based application can directly installed from GitHub at https://github.com/imohamme/tethys_nasaaccess.

NASAaccess is an open-source software package under NASA Open Source Agreement v1.3.

On a local machine the user should have installed the following programs as well as setting up a user account. The list below gives a summary of what is needed to be done prior to work with NASAaccess software on any local machine:

• Installing R software

• Installing Rstudio software (OPTIONAL)

• NASAaccess R package needs a user registration access with Earthdata. Users should set up a registration account(s) with Earthdata login as well as well as authorizing NASA GES DISC data access. Please refer to https://disc.gsfc.nasa.gov/information/documents Data Access section for further details.

• curl software . Since Mac users have curl as part of macOS build, Windows users should make sure that their local machines build have curl installed properly.

  • Checking if you can run curl from your command prompt. Type curl --help and you should see the help pages for the curl program once everything is defined correctly.

• Within Rstudio or R terminal run the following commands to install NASAaccess:

  • library(devtools)

  • install_github("nasa/NASAaccess", build_vignettes = TRUE)

  • library(NASAaccess)

Within the Rstudio help tab the user can verify that the package has been installed and browse the help pages of the various functions of NASAaccess. The GES DISC user registration access logging information will be processed by masking (i.e., not displaying the lieteral typed text as input) on most but not all platforms. Without providing GES DISC user registration access logging information, the user will receive ‘You need to provide your Earthdata GES DISC login to proceed…’ message.

• NASAaccess conda package needs a user registration access with Earthdata. Users should set up a registration account(s) with Earthdata login as well as well as authorizing NASA GES DISC data access. Please refer to https://disc.gsfc.nasa.gov/information/documents Data Access section for further details.

  • Creating the .netrc file at the user machine Home directory and storing the user NASA GES DISC logging information in it is done automatically to execute the NASAaccess package commands. Accessing data from NASA servers is further explained at Here. The GES DISC user registration access logging information will be processed by masking in the terminal on any major OS. Without providing GES DISC user registration access logging information, the user will receive ‘You need to provide your Earthdata GES DISC login to proceed…’ message.

• To install NASAaccess package in a conda environment run the following:

conda install -c conda-forge r-nasaaccess

Full details on installing the web-based application of NASAaccess on single machines and local servers can be found at readthedocs.

Software users are encouraged to visit (https://imohamme.github.io/NASAaccess/) to learn more on NASAaccess functionality and capabilities.

citation(package = 'NASAaccess')
#> To cite package 'NASAaccess' in publications use:
#> 
#>   Mohammed I (2023). _NASAaccess: Downloading and Reformatting Tool for
#>   NASA Earth Observation Data Products_. R package version 3.4.3,
#>   <https://github.com/nasa/NASAaccess>.
#> 
#> A BibTeX entry for LaTeX users is
#> 
#>   @Manual{,
#>     title = {{NASAaccess}: Downloading and Reformatting Tool for NASA Earth Observation Data Products},
#>     author = {Ibrahim Mohammed},
#>     year = {2023},
#>     institution = {National Aeronautics and Space Administration, Goddard Space Flight Center},
#>     address = {Greenbelt, Maryland},
#>     note = {R package version 3.4.3},
#>     url = {https://github.com/nasa/NASAaccess},
#>   }

Mohammed, I.N., Bustamante, E.G.R., Bolten, J.D., Nelson, E.J., 2023. Technical note: NASAaccess – a tool for access, reformatting, and visualization of remotely sensed earth observation and climate data. Hydrol. Earth Syst. Sci. 27, 3621-3642, https://doi.org/10.5194/hess-27-3621-2023