Get_all_Ocean_Prod2: Download multiple SeaWiFS or MODIS HDF4 file from Ocean...

In chihlinwei/OceanData: Tools to download and extract oceanographic data from various sources

Download multiple SeaWiFS or MODIS HDF4 file from Ocean Productivity Web page using ncdf4 package

Description

Download multiple SeaWiFS or MODIS HDF4 file from Ocean Productivity Web page and then convert to a raster object

Usage

Get_all_Ocean_Prod2(url_list, ts, outdir = NULL)

Arguments

url_list	A list string for each variable naming the time-series URLs of HDF4 file to be downloaded. The names of the url_list (names(url_list)) should be given as a vector of variable names.
ts	The number of urls to be download in url_list to be retrived. If not provide, returning full data set.
outdir	output directory to write raster file

Details

This is an R wrapper for the Get_Ocean_Prod2 functions. This function downloads multiple HDF4 files from Ocean Productivity Web page http://www.science.oregonstate.edu/ocean.productivity/

Value

a raster object

Author(s)

Chih-Lin Wei <[e-mail]>

Examples

#### Get chl & vgpm from 2002-07 to 2021-12 (using MODIS) 
# Create a folder to output raster bricks 
folder <- "Mothly_Ocean_Productivity_MODIS_Standard_VGPM_2002_2021"
dir.create(folder)
# Year and day of year by month from 2002-07-01 to 2021-12-01
modis <- Year_Day("2002-07-01", "2021-12-01", by="month") # MODIS time series

# URLs for each variable
# The url path may change depending on the NASA Ocean Color reprocessing version
# Check http://www.science.oregonstate.edu/ocean.productivity/ before using the following examplea

# Chlorophyll concentration
chl <- paste("http://orca.science.oregonstate.edu/data/2x4/monthly/chl.modis.r2018/hdf/chl", modis, "hdf.gz", sep=".")

# Vertical General Production model
vgpm <- paste("http://orca.science.oregonstate.edu/data/2x4/monthly/vgpm.r2018.m.chl.m.sst/hdf/vgpm", modis, "hdf.gz", sep=".")

url_list <- list(chl, vgpm)
names(url_list) <- c("chl", "vgpm")

# No data in August and September 2020
for(i in c(1:217, 220:234)) Get_all_Ocean_Prod2(url_list, ts=i, outdir=folder)

chihlinwei/OceanData documentation built on Jan. 17, 2025, 4:24 a.m.