greenSD (version 0.1.1)

sample_values: Sample greenspace-realted data from Greenspace Seasonality Data Cube, ESA WorldCover 10m Annual Composites Dataset, or Sentinel-2-l2a images.

Description

Samples values by locatoins from the Greenspace Seasonality Data Cube developed by Wu et al. (2024), ESA WorldCover 10m Annual Composites Dataset by Zanaga et al. (2021), or Sentinel-2-l2a images.

Usage

sample_values(
  samples = NULL,
  time = NULL,
  source = "gsdc",
  output_bands = NULL,
  cloud_cover = 10,
  vege_perc = 0,
  select = "latest",
  method = "first",
  quiet = TRUE
)

Value

A data.frame containing greenspace values extracted at each point across all bands. Each row corresponds to a sample location; columns represent band values.

Arguments

samples

A list, matrix, data.frame, or sf object of point locations. Can be a list of length-2 numeric vectors (list(c(lon, lat))), a 2-column matrix or data.frame, or an sf object with POINT geometry in any CRS.

time

numeric or vector. The time of interest. See Detail.

source

character. The data source for extracting greenspace values: gsdc for Greenspace Seasonality Data Cube (also see get_gsdc()]), esa_ndvior esa_landcover for ESA WorldCover 10m Annual Dataset (also see get_esa_wc()]), and s2a_ndvi or s2a_bands for Sentinel-2-l2a image data (also see get_s2a_ndvi()]). The default is gsdc.

output_bands

vector. A list of band names (c('B04', 'B08')). The default is NULL. (Only required, when source = "s2a_bands") All available bands can be found here

cloud_cover

numeric. The percentage of cloud coverage for retrieving Sentinel-2-l2a images. (Only required, when source = "s2a_ndvi" or source = "s2a_bands")

vege_perc

numeric. The percentage of cloud coverage for retrieving Sentinel-2-l2a images. (Only required, when source = "s2a_ndvi" or source = "s2a_bands")

select

character. one of "latest", "earliest", "all". The default is "latest".

method

character. A method for mosaicing layers: one of "mean", "median", "min", "max", "modal", "sum", "first", "last". The default is "first".

quiet

logical. Whether show progress bars for some process.

Details

time: For the greenspace seasonality data cube, only years from 2019 to 2022 are availabe. For ESA WorldCover 10m Annual Composites Dataset, only 2020 and 2021 are available.

References

Wu, S., Song, Y., An, J. et al. High-resolution greenspace dynamic data cube from Sentinel-2 satellites over 1028 global major cities. Sci Data 11, 909 (2024). https://doi.org/10.1038/s41597-024-03746-7

Zanaga, D., Van De Kerchove, R., De Keersmaecker, W., Souverijns, N., Brockmann, C., Quast, R., Wevers, J., Grosu, A., Paccini, A., Vergnaud, S., Cartus, O., Santoro, M., Fritz, S., Georgieva, I., Lesiv, M., Carter, S., Herold, M., Li, L., Tsendbazar, N.-E., … Arino, O. (2021). ESA WorldCover 10 m 2020 v100 (Version v100). Zenodo. https://doi.org/10.5281/zenodo.5571936

Zanaga, D., Van De Kerchove, R., Daems, D., De Keersmaecker, W., Brockmann, C., Kirches, G., Wevers, J., Cartus, O., Santoro, M., Fritz, S., Lesiv, M., Herold, M., Tsendbazar, N.-E., Xu, P., Ramoino, F., & Arino, O. (2022). ESA WorldCover 10 m 2021 v200 (Version v200). Zenodo. https://doi.org/10.5281/zenodo.7254221

Examples

# see supported urban areas and their boundaries
check_available_urban()
boundary <- check_urban_boundary(uid = 11)

# sample locations with in the boundary
samples <- sf::st_sample(boundary, size = 20)

# extract values
gs_samples <- sample_values(samples,
                            # time = 2022
                           )