I am relatively new to R studio and I was instructed to draw a graph showing seasonality using daily rainfall over a number of years. I need help more in interpreting the graph than in plotting it.

There is an example already in r using mscdata that i was able to replicate using my own data, the code for the example is as below. Any help with what this graph means or explains will be greatly appreciated.Thank you

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install.packages(seas)

library(seas)

data(mscdata)

dat <- mksub(mscdata, id=1108447)

dat.ss <- seas.sum(dat, width="mon")

x<-mscdata

# Structure in R

str(dat.ss)

tail(mscdata)

# Annual data

dat.ss$ann

# Demonstrate how to slice through a cubic array

dat.ss$seas["1990",,]

dat.ss$seas[,2,] # or "Feb", if using English locale

dat.ss$seas[,,"precip"]

# Simple calculation on an array

(monthly.mean <- apply(dat.ss$seas[,,"precip"], 2, mean,na.rm=TRUE))

barplot(monthly.mean, ylab="Mean monthly total (mm/month)",

main="Un-normalized mean precipitation in Vancouver, BC")

text(6.5, 150, paste("Un-normalized rates given 'per month' should be",

"avoided since ~3-9% error is introduced",

"to the analysis between months", sep="\n"))

# Normalized precip

norm.monthly <- dat.ss$seas[,,"precip"] / dat.ss$days

norm.monthly.mean <- apply(norm.monthly, 2, mean,na.rm=TRUE)

print(round(norm.monthly, 2))

print(round(norm.monthly.mean, 2))

barplot(norm.monthly.mean,

ylab="Normalized mean monthly total (mm/day)",

main="Normalized mean precipitation in Vancouver, BC")

# Better graphics of data

dat.ss <- seas.sum(dat, width=11)

image(dat.ss)

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