sfbay {wql}

San Francisco Bay water quality data

Description

Selected observations and variables from U.S. Geological Survey water quality stations in south San Francisco Bay. Data include CTD and nutrient measurements.

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 variable names. sfbayChla was constructed from the entire downloaded sfbay dataset and encompasses the period 1969–2009.

Source

Downloaded from https://sfbay.wr.usgs.gov/water-quality-database/ on 2009-11-17.

Examples

data(sfbay)
str(sfbay)
str(sfbayStns)
str(sfbayVars)
plot(sfbayChla[, 1:10], main = "SF Bay Chl-a")