Monthly Pacific Decadal Oscillation (PDO) index values from January 1900 to February 2017. Includes download_pdo() to scrape the latest values from < http://research.jisao.washington.edu/pdo/PDO.latest>.
rpdo is an R data package of Monthly Pacific Decadal Oscillation (PDO) index values from January 1900 to present.
library(rpdo)library(ggplot2)ggplot(data = subset(rpdo::pdo, pdo$Month == 1), aes(x = Year, y = PDO)) +geom_smooth(span = 0.1, se = FALSE, color = "black") + geom_point() + ylab("January PDO Index")
Pacific Decadal Oscillation (PDO) Index for January by year.
rpdo also provides the function
download_pdo() to scrape the most recent data from the website http://research.jisao.washington.edu/pdo/PDO.latest.
To install and load the most recent release from CRAN
To install and load the development version from GitHub
The PDO index values are derived as the leading PC of monthly SST anomalies in the North Pacific Ocean, poleward of 20N. The monthly mean global average SST anomalies are removed to separate this pattern of variability from any "global warming" signal that may be present in the data.
For more details, see:
Zhang, Y., J.M. Wallace, D.S. Battisti, 1997: ENSO-like interdecadal variability: 1900-93. J. Climate, 10, 1004-1020.
Mantua, N.J. and S.R. Hare, Y. Zhang, J.M. Wallace, and R.C. Francis,1997: A Pacific interdecadal climate oscillation with impacts on salmon production. Bulletin of the American Meteorological Society, 78, pp. 1069-1079.
Data sources for this index are: UKMO Historical SST data set for 1900-81; Reynold's Optimally Interpolated SST (V1) for January 1982-Dec 2001 and OI SST Version 2 (V2) beginning January 2002.
download_pdoto allow users to get most recent data from web.
vignette("rpdo")information to README.