Exploring the NOAA Strom Database about sever weather events

Synopsis

Severe weather events like storm can cause damage to properties and living beings on earth.

This project involves exploring the U.S. National Oceanic and Atmospheric Administration’s (NOAA) storm database. This database tracks characteristics of major storms and weather events in the United States, including when and where they occur, as well as estimates of any fatalities, injuries, and property damage.

The analysis of data should address the following * Across the United States, which types of events (as indicated in the EVTYPE variable) are most harmful with respect to population health ? * Across the United States, which types of events have the greatest economic consequences ?

Libraries

library(knitr)
library(ggplot2)

Data Processing

if(!file.exists("stormData.csv.bz2")) {
  download.file("https://d396qusza40orc.cloudfront.net/repdata%2Fdata%2FStormData.csv.bz2",
  destfile = "stormData.csv.bz2")
}

# Loading data
data <- read.csv(bzfile("stormData.csv.bz2"), sep=",", header=T)
head(data)
##   STATE__           BGN_DATE BGN_TIME TIME_ZONE COUNTY COUNTYNAME STATE  EVTYPE
## 1       1  4/18/1950 0:00:00     0130       CST     97     MOBILE    AL TORNADO
## 2       1  4/18/1950 0:00:00     0145       CST      3    BALDWIN    AL TORNADO
## 3       1  2/20/1951 0:00:00     1600       CST     57    FAYETTE    AL TORNADO
## 4       1   6/8/1951 0:00:00     0900       CST     89    MADISON    AL TORNADO
## 5       1 11/15/1951 0:00:00     1500       CST     43    CULLMAN    AL TORNADO
## 6       1 11/15/1951 0:00:00     2000       CST     77 LAUDERDALE    AL TORNADO
##   BGN_RANGE BGN_AZI BGN_LOCATI END_DATE END_TIME COUNTY_END COUNTYENDN
## 1         0                                               0         NA
## 2         0                                               0         NA
## 3         0                                               0         NA
## 4         0                                               0         NA
## 5         0                                               0         NA
## 6         0                                               0         NA
##   END_RANGE END_AZI END_LOCATI LENGTH WIDTH F MAG FATALITIES INJURIES PROPDMG
## 1         0                      14.0   100 3   0          0       15    25.0
## 2         0                       2.0   150 2   0          0        0     2.5
## 3         0                       0.1   123 2   0          0        2    25.0
## 4         0                       0.0   100 2   0          0        2     2.5
## 5         0                       0.0   150 2   0          0        2     2.5
## 6         0                       1.5   177 2   0          0        6     2.5
##   PROPDMGEXP CROPDMG CROPDMGEXP WFO STATEOFFIC ZONENAMES LATITUDE LONGITUDE
## 1          K       0                                         3040      8812
## 2          K       0                                         3042      8755
## 3          K       0                                         3340      8742
## 4          K       0                                         3458      8626
## 5          K       0                                         3412      8642
## 6          K       0                                         3450      8748
##   LATITUDE_E LONGITUDE_ REMARKS REFNUM
## 1       3051       8806              1
## 2          0          0              2
## 3          0          0              3
## 4          0          0              4
## 5          0          0              5
## 6          0          0              6
#Creating a tidy data by subsetting the required values
tidydata <- data[,c('EVTYPE','FATALITIES','INJURIES', 'PROPDMG', 'PROPDMGEXP', 'CROPDMG', 'CROPDMGEXP')]
head(tidydata,10)
##     EVTYPE FATALITIES INJURIES PROPDMG PROPDMGEXP CROPDMG CROPDMGEXP
## 1  TORNADO          0       15    25.0          K       0           
## 2  TORNADO          0        0     2.5          K       0           
## 3  TORNADO          0        2    25.0          K       0           
## 4  TORNADO          0        2     2.5          K       0           
## 5  TORNADO          0        2     2.5          K       0           
## 6  TORNADO          0        6     2.5          K       0           
## 7  TORNADO          0        1     2.5          K       0           
## 8  TORNADO          0        0     2.5          K       0           
## 9  TORNADO          1       14    25.0          K       0           
## 10 TORNADO          0        0    25.0          K       0
str(tidydata)
## 'data.frame':    902297 obs. of  7 variables:
##  $ EVTYPE    : chr  "TORNADO" "TORNADO" "TORNADO" "TORNADO" ...
##  $ FATALITIES: num  0 0 0 0 0 0 0 0 1 0 ...
##  $ INJURIES  : num  15 0 2 2 2 6 1 0 14 0 ...
##  $ PROPDMG   : num  25 2.5 25 2.5 2.5 2.5 2.5 2.5 25 25 ...
##  $ PROPDMGEXP: chr  "K" "K" "K" "K" ...
##  $ CROPDMG   : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ CROPDMGEXP: chr  "" "" "" "" ...

Inorder to find out the damage caused We have to make use of

PROPDMG and CROPDMG which indicates the amount of property and crop damage

PROPDMGEXP and CROPDMGEXP have Unit expressed in power of 10 of the above variables (H,K,M B means Hundreds, Thousands, Millions and Billions respectively)

So have to convert them into proper units

#Converting H,K,M,B units in Property damage

tidydata$PROPDMGNUM = 0

# fill in the data with correct units
tidydata[tidydata$PROPDMGEXP == "H", ]$PROPDMGNUM = tidydata[tidydata$PROPDMGEXP == "H", ]$PROPDMG * 10^2
tidydata[tidydata$PROPDMGEXP == "K", ]$PROPDMGNUM = tidydata[tidydata$PROPDMGEXP == "K", ]$PROPDMG * 10^3
tidydata[tidydata$PROPDMGEXP == "M", ]$PROPDMGNUM = tidydata[tidydata$PROPDMGEXP == "M", ]$PROPDMG * 10^6
tidydata[tidydata$PROPDMGEXP == "B", ]$PROPDMGNUM = tidydata[tidydata$PROPDMGEXP == "B", ]$PROPDMG * 10^9

head(tidydata, 10)
##     EVTYPE FATALITIES INJURIES PROPDMG PROPDMGEXP CROPDMG CROPDMGEXP PROPDMGNUM
## 1  TORNADO          0       15    25.0          K       0                 25000
## 2  TORNADO          0        0     2.5          K       0                  2500
## 3  TORNADO          0        2    25.0          K       0                 25000
## 4  TORNADO          0        2     2.5          K       0                  2500
## 5  TORNADO          0        2     2.5          K       0                  2500
## 6  TORNADO          0        6     2.5          K       0                  2500
## 7  TORNADO          0        1     2.5          K       0                  2500
## 8  TORNADO          0        0     2.5          K       0                  2500
## 9  TORNADO          1       14    25.0          K       0                 25000
## 10 TORNADO          0        0    25.0          K       0                 25000
#Converting H,K,M,B units in Crop damage

tidydata$CROPDMGNUM = 0

# fill in the data with correct units
tidydata[tidydata$CROPDMGEXP == "H", ]$CROPDMGNUM = tidydata[tidydata$CROPDMGEXP == "H", ]$CROPDMG * 10^2
tidydata[tidydata$CROPDMGEXP == "K", ]$CROPDMGNUM = tidydata[tidydata$CROPDMGEXP == "K", ]$CROPDMG * 10^3
tidydata[tidydata$CROPDMGEXP == "M", ]$CROPDMGNUM = tidydata[tidydata$CROPDMGEXP == "M", ]$CROPDMG * 10^6
tidydata[tidydata$CROPDMGEXP == "B", ]$CROPDMGNUM = tidydata[tidydata$CROPDMGEXP == "B", ]$CROPDMG * 10^9

Results

Question 1: Across the United States, which types of events (as indicated in the EVTYPE variable) are most harmful with respect to population health ?

# ploting number of fatalities with the most harmful event type

fatalities <- aggregate(FATALITIES ~ EVTYPE, data=tidydata, sum)

fatalities <- fatalities[order(-fatalities$FATALITIES), ][1:10, ]
fatalities$EVTYPE <- factor(fatalities$EVTYPE, levels = fatalities$EVTYPE)

ggplot(fatalities, aes(x = EVTYPE, y = FATALITIES)) + 
    geom_bar(stat = "identity", fill = "pink", las = 3) + 
    theme(axis.text.x = element_text(angle = 90, hjust = 1)) + 
    xlab("Event Type") + ylab("Fatalities") + ggtitle("Number of fatalities by top 10 Weather Events")
## Warning: Ignoring unknown parameters: las

# ploting number of injuries with the most harmful event type

injuries <- aggregate(INJURIES ~ EVTYPE, data=tidydata, sum)
injuries <- injuries[order(-injuries$INJURIES), ][1:10, ]
injuries$EVTYPE <- factor(injuries$EVTYPE, levels = injuries$EVTYPE)

ggplot(injuries, aes(x = EVTYPE, y = INJURIES)) + 
    geom_bar(stat = "identity", fill = "pink", las = 3) + 
    theme(axis.text.x = element_text(angle = 90, hjust = 1)) + 
    xlab("Event Type") + ylab("Injuries") + ggtitle("Number of injuries by top 10 Weather Events")
## Warning: Ignoring unknown parameters: las

So from this we can conclude that the weather event that causes the most harm to public is Tornadoes. Because most injuries and fatalities are caused by it in United States

Question 2: Across the United States, which types of events has the greatest economic consequences?

# ploting number of damages with the most harmful event type

damages <- aggregate(PROPDMGNUM + CROPDMGNUM ~ EVTYPE, data=tidydata, sum)
names(damages) = c("EVTYPE", "TOTALDAMAGE")
damages <- damages[order(-damages$TOTALDAMAGE), ][1:10, ]
damages$EVTYPE <- factor(damages$EVTYPE, levels = damages$EVTYPE)

ggplot(damages, aes(x = EVTYPE, y = TOTALDAMAGE)) + 
    geom_bar(stat = "identity", fill = "pink", las = 3) + 
    theme(axis.text.x = element_text(angle = 90, hjust = 1)) + 
    xlab("Event Type") + ylab("Damages ($)") + ggtitle("Property & Crop Damages by top 10 Weather Events")
## Warning: Ignoring unknown parameters: las

So from this we can conclude that flood causes the greatest economic consequences