Selected observations and variables from U.S. Geological Survey water quality stations in south San Francisco Bay. Data include CTD and nutrient measurements.
Usage
sfbay
Format
sfbay is a data frame with 23207 observations (rows) of 12 variables (columns):
[, 1]
date
date
[, 2]
time
time
[, 3]
stn
station code
[, 4]
depth
measurement depth
[, 5]
chl
chlorophyll a
[, 6]
dox.pct
dissolved oxygen
[, 7]
spm
suspended particulate matter
[, 8]
ext
extinction coefficient
[, 9]
sal
salinity
[, 10]
temp
water temperature
[, 11]
nox
nitrate + nitrite
[, 12]
nhx
ammonium
sfbayStns is a data frame with 16 observations of 6 variables:
[, 1]
site
station code
[, 2]
description
station description
[, 3]
lat
latitude
[, 4]
long
longitude
[, 5]
depthMax
maximum depth, in m
[, 6]
distFrom36
distance from station 36, in km
sfbayVars is a data frame with 7 observations of 3 variables:
[, 1]
variable
water quality variable code
[, 2]
description
description
[, 3]
units
measurement units
sfbayChla is a time series matrix (380 months x 16 stations) of average 0-5 m chlorophyll a concentrations calculated from the data in sfbay.
Details
The original downloaded dataset was modified by taking a subset of six well-sampled stations and the period 1985–2004. Variable names were also simplified. The data frames sfbayStns and sfbayVars describe the stations and water quality variables in more detail; they were created from information at the same web site. Note that the station numbers in sfbayStns have been prefixed with s to make station codes into legal R variable names. sfbayChla was constructed from the entire downloaded sfbay dataset and encompasses the period 1969–2009.