wq (version 0.2-2)

sfbay: 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.

Usage

sfbay

Rdversion

1.1

docType

data

format

sfbay is a data frame with 23207 observations (rows) of 12 variables (columns):

rll{ [, 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:

rll{ [, 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:

rll{ [, 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.

source

Downloaded from http://sfbay.wr.usgs.gov/access/wqdata on 2009-11-17.

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

Examples

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