In bsmity13/snowdl: Download Various Sources of Snow Data

knitr::opts_chunk$set(
  collapse = TRUE,
  comment = "#>",
  fig.path = "man/figures/README-",
  out.width = "100%"
)

# Use 'badger' to place badges
library(badger)

# Data sources
ERA5 <- data.frame(Dataset = "ERA5-Land Hourly",
                   Source = "ECMWF",
                   Link = "<a href = 'https://cds.climate.copernicus.eu/cdsapp#!/dataset/10.24381/cds.e2161bac?tab=overview' target='_blank' rel='noopener noreferrer'>ERA5-Land</a>",
                   Citation = "DOI: <a href = 'https://doi.org/10.24381/cds.e2161bac' target='_blank' rel='noopener noreferrer'>10.24381/cds.e2161bac</a>")

SNODAS <- data.frame(Dataset = "SNODAS",
                     Source = "NOAA",
                     Link = "<a href = 'https://nsidc.org/data/g02158' target='_blank' rel='noopener noreferrer'>NSIDC</a>",
                     Citation = "DOI: <a href = 'https://doi.org/10.7265/N5TB14TC' target='_blank' rel='noopener noreferrer'>10.7265/N5TB14TC</a>")

Daymet <- data.frame(Dataset = "Daymet v4",
                     Source = "NASA",
                     Link = "<a href = 'https://daac.ornl.gov/DAYMET/guides/Daymet_Daily_V4.html' target='_blank' rel='noopener noreferrer'>ORNL DAAC</a>",
                     Citation = "<a href = 'https://daymet.ornl.gov/files/Thornton_Daymet_V4_submitted_2021-01-20.pdf' target='_blank' rel='noopener noreferrer'>Thornton et al. 2020</a>")

# Combine
data_sources <- rbind(ERA5, SNODAS, Daymet)

# Sort
data_sources <- data_sources[order(data_sources$Dataset), ]

snowdl

r badge_license("GPL-3") r badge_custom("repo status", "WIP", "yellow", "https://www.repostatus.org/#wip") r badge_devel("bsmity13/snowdl", "blue")

The goal of snowdl is to make it easy to download snow data (e.g., snow depth, snow density, snow-water equivalent) from various sources (see below).

Installation

Install the development version from GitHub with:

# install.packages("devtools")
devtools::install_github("bsmity13/snowdl")

This package is not yet operational. Check back soon for progress!

Available data sources

Sorted alphabetically by dataset name

r knitr::kable(data_sources, row.names = FALSE, escape = TRUE)

Important Notes

• Daymet is probably not a great source for SWE. Based on my reading, they treat it more like a nuisance parameter than a quanity of interest. See this link for their Snow Water Equivalent Clarification. Note, this clarification was made in reference to V3, but still applies based on newest literature for V4.

• Further, Daymet has (apparently) different units for SWE than other sources (but not really). Daymet uses kg/m^2, while other sources use m (depth if snow was melted). To convert, multiply by area of the pixel (kg/m^2 * m^2/1 = kg) to get mass of water, convert to cubic meters (1 kg = 1 L H2O = 0.001 m^3), and then get depth by dividing by area (m^3/1 * 1/m^2 = m). Perhaps more useful to have units in mm, so again multiply by 0.001 m = 1 mm.

  • Note Daymet comes with lcc projection and units = m. Resolution is 1000 x 1000, so area is 1e6 m^2.
  • Therefore, conversion becomes x * 1e6 * 0.001 * 0.001. All conversions cancel and resulting units are mm.
  • To be clear, kg/m^2 = mm in this case.

Package Status/To-dos

• [x] Basic functionality
  • [x] Download Daymet and process
  • [x] Download ERA5 and process
  • [x] Download SNODAS and process
• [ ] User-friendly wrappers
  • [ ] Iterate over dates
  • [ ] Complete entire workflow in tempdir()
• [ ] Other data sources?
• [ ] Vignettes
  • [ ] Overview/Quickstart using wrapper functions
  • [ ] In-depth using basic functionality

bsmity13/snowdl documentation built on Feb. 24, 2024, 9:03 p.m.