daymetr

A programmatic interface to the Daymet web
services. Allows for easy downloads of Daymet
climate data directly to your R workspace or your computer. Routines for
both single pixel data downloads and gridded (netCDF) data are provided.
Please use the below citation when using the package.

We received news from Dr. Michele Thornton at the Oak Ridge National Laboratory (ORNL) that the DAYMET API they host will be decommissioned. This change will be effective within weeks (late March 2025) and affect first and foremost the spatial (gridded/tiled) data products, before most likely covering the whole THREDDS data server setup including point based data by the end of the year. We suggest that users of our {daymetr} R package migrate to the NASA EarthData Appeears based API as covered by our {appeears} R package.

How to cite this package

Hufkens K., Basler J. D., Milliman T. Melaas E., Richardson A.D. 2018
An integrated phenology modelling framework in R: Phenology modelling
with phenor. Methods in Ecology &
Evolution, 9: 1-10. https://doi.org/10.1111/2041-210X.12970

Installation

stable release

To install the current stable release use a CRAN repository:

install.packages("daymetr")
library("daymetr")

development release

To install the development releases of the package run the following
commands:

if(!require(remotes)){install.packages("remotes")}
remotes::install_github("bluegreen-labs/daymetr")
library("daymetr")

Vignettes are not rendered by default, if you want to include additional
documentation please use:

if(!require(remotes)){install.packages("remotes")}
remotes::install_github("bluegreen-labs/daymetr", build_vignettes = TRUE)
library("daymetr")

Use

Single pixel location download

For a single site use the following format

download_daymet(site = "Oak Ridge National Laboratories",
                lat = 36.0133,
                lon = -84.2625,
                start = 1980,
                end = 2010,
                internal = TRUE)

Batch mode uses similar parameters but you provide a comma separated
file with site names and latitude longitude which are sequentially
downloaded. The format of the comma separated file is: site name,
latitude, longitude.

download_daymet_batch(file_location = 'my_sites.csv',
                      start = 1980,
                      end = 2010,
                      internal = TRUE)

Gridded data downloads

For gridded data use either download_daymet_tiles() for individual
tiles or download_daymet_ncss() for a netCDF subset which is not bound
by tile limits (but restricted to a 6GB query size).

Tiled data

download_daymet_tiles(location = c(36.0133,-84.2625),
                      tiles = NULL,
                      start = 1980,
                      end = 2012,
                      param = "ALL")

If only the first set of coordinates is provided the tile in which these
reside is downloaded. If your region of interest falls outside the scope
of the DAYMET data coverage a warning is issued. If both top left and
bottom right coordinates are provided all tiles covering the region of
interst are downloaded. I would caution against downloading too much
data, as file sizes do add up. So be careful how you specify your region
of interest.

netCDF subset (ncss) data

download_daymet_ncss(location = c(36.61,-85.37,33.57,-81.29),
                     start = 1980,
                     end = 1980,
                     param = "tmin")

Keep in mind that the bounding box is defined by the minimum (square)
bounding box in a Lambert Conformal Conic (LCC) projection as defined by
the provided geographic coordinates. In general the query area will be
larger than the requested location. For more information I refer to
Daymet documentation on the
web service.

Acknowledgements

This project was supported by the National Science Foundation’s
Macro-system Biology Program (awards EF-1065029 and EF-1702697) and the Marie Skłodowska-Curie Action (H2020 grant 797668). Logo design elements are taken from the FontAwesome library according to these terms, where the globe element was inverted and intersected.