Benthic stack

The benthic d18O LR4 stack spans 5.3Ma. It is based on an average of 57 benthic d18O records (which measure global ice volume and deep ocean temperature), globally distributed sites along the Earth. Among with the ice cores (from Antartida and Greenland), the benthic stack provides an independent proxy, as a template for global clima and a stratrigraphic tool for paleoceanographers. For example, using the benthic stack we can identify the glacial cycles, climate cycles from Martrat et al. (2004) or marine isotopic stages (so called MIS).

References:
Lisiecki, L. E., and M. E. Raymo (2005), A Pliocene-Pleistocene stack of 57 globally distributed benthic d18O records,
Paleoceanography, 20, PA1003, doi:10.1029/2004PA001071

Here I show a simple code to download it directly from the internet (don't forget to cite), so we can use it in R. No extra packages needed. The plot shown is just a simple example for the first 500 ka (note also the way to write the legend, where d18O is on a correct syntax, I hope :) which I was unable to do in blogger).



# Benthic stack 

 # database created with 1000 corers around the world. 
 # http://lorraine-lisiecki.com/stack.html

 # Please cite: Lisiecki, L. E., and M. E. Raymo (2005), A Pliocene-
 # Pleistocene stack of 57 globally distributed benthic d18O records, 
 # Paleoceanography,20, PA1003, doi:10.1029/2004PA001071.  
 # readLines("http://lorraine-lisiecki.com/LR04stack.txt")
 benthic.stack=read.table("http://lorraine-lisiecki.com/LR04stack.txt", skip=5, col.names=c("age","d18O","se")); 
 benthic.stack$d18O=benthic.stack$d18O*-1
 plot(d18O~c(age), benthic.stack[benthic.stack$age<450,], typ="l", col=4, xlab="Age (ka)", ylab=expression(paste(delta^18~O," Benthic stack")))
 abline(v=seq(round(min(benthic.stack$age)),round(max(benthic.stack$age)), by=20), col=8, lty=3)

Created by Pretty R at inside-R.org

Eccentricity, Obliquity and Precession

The Earth climate is primarily influenced by the Sun,
thus changes in the orbital variations are generally
considered in paleoceanographic studies. Thus,
my first step was to download this data.
In this code, you download the data directly from the net,
and plot it in R. No extra packages required.

#  Orbital Variations and Insolation Database: Insolation.readme file
 orbit=read.table("ftp://ftp.ncdc.noaa.gov/pub/data/paleo/insolation/orbit91", 
      skip=3, col.names=c("age", "ECC","OMEGA","OBL","PREC","I65NJul","I65SJan","I15NJul","I15SJan"))
 #summary(orbit)
 orbit$age=abs(orbit$age)
 par(mfrow=c(2,2), mar=c(4,4,1,1), cex=.7)
 plot(ECC~age, orbit[orbit$age<450,], typ="l", col=4, main="Eccentricity")
 plot(OMEGA~age, orbit[orbit$age<450,], typ="l", col=2)
 plot(OBL~age, orbit[orbit$age<450,], typ="l", col=3, main="Obliquity")
 plot(PREC~age, orbit[orbit$age<450,], typ="l", col=5, main="Precession")

Created by Pretty R at inside-R.org

 And than you get something like this: