Title: “StormData Analysis using NOAA Data to analyse about severe weather Events
Author: “Suganthi M”
Date: “January 15, 2017”

Synopsis

This project involves analysis of the stormdata from 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 events in the database start in the year 1950 and end in November 2011.

The analysis involves fetching the data from NOAA, processing it ,cleaning it and computing the Events that cause the most harm impacts to the population with respect to their health and also the Events that causes the most economic consequences.From the Analysis we determine that Tornado causes the most fatalties and Injuries while Flood and Drought causes the most ecnomic damages.

Data Processing

The Data is downloaded from here and placed in the working directory.

library(ggplot2)
library(dplyr)
## 
## Attaching package: 'dplyr'
## The following objects are masked from 'package:stats':
## 
##     filter, lag
## The following objects are masked from 'package:base':
## 
##     intersect, setdiff, setequal, union
library(knitr)
library(reshape2)
library(gridExtra)
## 
## Attaching package: 'gridExtra'
## The following object is masked from 'package:dplyr':
## 
##     combine
stormdata<-read.csv("repdataFdataStormData.csv.bz2")

Analysis

Once the data is loaded in R, lets look at the data set

str(stormdata)
## 'data.frame':    902297 obs. of  37 variables:
##  $ STATE__   : num  1 1 1 1 1 1 1 1 1 1 ...
##  $ BGN_DATE  : Factor w/ 16335 levels "1/1/1966 0:00:00",..: 6523 6523 4242 11116 2224 2224 2260 383 3980 3980 ...
##  $ BGN_TIME  : Factor w/ 3608 levels "00:00:00 AM",..: 272 287 2705 1683 2584 3186 242 1683 3186 3186 ...
##  $ TIME_ZONE : Factor w/ 22 levels "ADT","AKS","AST",..: 7 7 7 7 7 7 7 7 7 7 ...
##  $ COUNTY    : num  97 3 57 89 43 77 9 123 125 57 ...
##  $ COUNTYNAME: Factor w/ 29601 levels "","5NM E OF MACKINAC BRIDGE TO PRESQUE ISLE LT MI",..: 13513 1873 4598 10592 4372 10094 1973 23873 24418 4598 ...
##  $ STATE     : Factor w/ 72 levels "AK","AL","AM",..: 2 2 2 2 2 2 2 2 2 2 ...
##  $ EVTYPE    : Factor w/ 985 levels "   HIGH SURF ADVISORY",..: 834 834 834 834 834 834 834 834 834 834 ...
##  $ BGN_RANGE : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ BGN_AZI   : Factor w/ 35 levels "","  N"," NW",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ BGN_LOCATI: Factor w/ 54429 levels "","- 1 N Albion",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ END_DATE  : Factor w/ 6663 levels "","1/1/1993 0:00:00",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ END_TIME  : Factor w/ 3647 levels ""," 0900CST",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ COUNTY_END: num  0 0 0 0 0 0 0 0 0 0 ...
##  $ COUNTYENDN: logi  NA NA NA NA NA NA ...
##  $ END_RANGE : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ END_AZI   : Factor w/ 24 levels "","E","ENE","ESE",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ END_LOCATI: Factor w/ 34506 levels "","- .5 NNW",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ LENGTH    : num  14 2 0.1 0 0 1.5 1.5 0 3.3 2.3 ...
##  $ WIDTH     : num  100 150 123 100 150 177 33 33 100 100 ...
##  $ F         : int  3 2 2 2 2 2 2 1 3 3 ...
##  $ MAG       : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ 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: Factor w/ 19 levels "","-","?","+",..: 17 17 17 17 17 17 17 17 17 17 ...
##  $ CROPDMG   : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ CROPDMGEXP: Factor w/ 9 levels "","?","0","2",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ WFO       : Factor w/ 542 levels ""," CI","$AC",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ STATEOFFIC: Factor w/ 250 levels "","ALABAMA, Central",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ ZONENAMES : Factor w/ 25112 levels "","                                                                                                                               "| __truncated__,..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ LATITUDE  : num  3040 3042 3340 3458 3412 ...
##  $ LONGITUDE : num  8812 8755 8742 8626 8642 ...
##  $ LATITUDE_E: num  3051 0 0 0 0 ...
##  $ LONGITUDE_: num  8806 0 0 0 0 ...
##  $ REMARKS   : Factor w/ 436781 levels "","-2 at Deer Park\n",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ REFNUM    : num  1 2 3 4 5 6 7 8 9 10 ...

The analysis requires us to find answers for the following two questions:

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

  2. Across the United States, which types of events have the greatest economic consequences?

Most Harmful Effects with respect to Population Health

Fatalities and Injuries are the columns that provides the data pertaining to the population health.

First summarize the data Fatalities based on Event type

stormFatalities<-aggregate(FATALITIES~EVTYPE,stormdata, sum)

Arrange the dataset in descending order to find the most impact

stormFatalities<-arrange(stormFatalities,desc(FATALITIES))

The total observations are

dim(stormFatalities)
## [1] 985   2

Fetch the top 10 events

stormtopFatalities<-stormFatalities[1:10,]

Lets take a look at the top 10 events to health

stormtopFatalities
##            EVTYPE FATALITIES
## 1         TORNADO       5633
## 2  EXCESSIVE HEAT       1903
## 3     FLASH FLOOD        978
## 4            HEAT        937
## 5       LIGHTNING        816
## 6       TSTM WIND        504
## 7           FLOOD        470
## 8     RIP CURRENT        368
## 9       HIGH WIND        248
## 10      AVALANCHE        224

We need to do the same steps to calculate the Injuries. Summarize Injuries by event type

stormInjuries<-aggregate(INJURIES~EVTYPE,stormdata, sum)

Sort the Injuries data in Descending order

stormInjuries<-arrange(stormInjuries,desc(INJURIES))

Pick the Top 10

stormtopInjuries<-stormInjuries[1:10,]

Lets look at the data

stormtopInjuries
##               EVTYPE INJURIES
## 1            TORNADO    91346
## 2          TSTM WIND     6957
## 3              FLOOD     6789
## 4     EXCESSIVE HEAT     6525
## 5          LIGHTNING     5230
## 6               HEAT     2100
## 7          ICE STORM     1975
## 8        FLASH FLOOD     1777
## 9  THUNDERSTORM WIND     1488
## 10              HAIL     1361

Events with the greatest economic consequences

The second part of the assignment is to see which events causes the greatest economic consequnces. To Analyse this, we need to look at the Property Damages and crop damages.

names(stormdata)
##  [1] "STATE__"    "BGN_DATE"   "BGN_TIME"   "TIME_ZONE"  "COUNTY"    
##  [6] "COUNTYNAME" "STATE"      "EVTYPE"     "BGN_RANGE"  "BGN_AZI"   
## [11] "BGN_LOCATI" "END_DATE"   "END_TIME"   "COUNTY_END" "COUNTYENDN"
## [16] "END_RANGE"  "END_AZI"    "END_LOCATI" "LENGTH"     "WIDTH"     
## [21] "F"          "MAG"        "FATALITIES" "INJURIES"   "PROPDMG"   
## [26] "PROPDMGEXP" "CROPDMG"    "CROPDMGEXP" "WFO"        "STATEOFFIC"
## [31] "ZONENAMES"  "LATITUDE"   "LONGITUDE"  "LATITUDE_E" "LONGITUDE_"
## [36] "REMARKS"    "REFNUM"

From the above, we notice that there are four columns related to Damages in the data set–> PROPDMG,PROPDMGEXP,CROPDMG and CROPDMGEXP

In order to calculate the damages,we need to convert PROPDMG and CROPDMG based on the exponent values represented in columns PROPDMGEXP and CROPDMGEXP respectively,

unique(stormdata$PROPDMGEXP)
##  [1] K M   B m + 0 5 6 ? 4 2 3 h 7 H - 1 8
## Levels:  - ? + 0 1 2 3 4 5 6 7 8 B h H K m M

Values B means Billion(100000000), M - Million(1000000) , K- Thousands(1000), numbers 1 to 8 denotes the number of zeroes to be added after 1 .

The transformation for property damages based on the exponent would be as below:

stormdata[stormdata$PROPDMGEXP == "K"|stormdata$PROPDMGEXP == "3", ]$PROPDMG<- stormdata[stormdata$PROPDMGEXP == "K"|stormdata$PROPDMGEXP == "3", ]$PROPDMG*1000
stormdata[stormdata$PROPDMGEXP == "M"|stormdata$PROPDMGEXP == "m" |stormdata$PROPDMGEXP == "6", ]$PROPDMG<- stormdata[stormdata$PROPDMGEXP == "M"|stormdata$PROPDMGEXP == "m"|stormdata$PROPDMGEXP == "6", ]$PROPDMG*1000000
 stormdata[stormdata$PROPDMGEXP == "B", ]$PROPDMG<-stormdata[stormdata$PROPDMGEXP == "B",]$PROPDMG*1000000000
 stormdata[stormdata$PROPDMGEXP == "8", ]$PROPDMG<-stormdata[stormdata$PROPDMGEXP == "8",]$PROPDMG*100000000
 stormdata[stormdata$PROPDMGEXP == "7", ]$PROPDMG<-stormdata[stormdata$PROPDMGEXP == "7",]$PROPDMG*10000000
 stormdata[stormdata$PROPDMGEXP == "5", ]$PROPDMG<- stormdata[stormdata$PROPDMGEXP == "5",]$PROPDMG*100000
 stormdata[stormdata$PROPDMGEXP == "4", ]$PROPDMG<- stormdata[stormdata$PROPDMGEXP == "4",]$PROPDMG*10000
 stormdata[stormdata$PROPDMGEXP == "2", ]$PROPDMG<- stormdata[stormdata$PROPDMGEXP == "2",]$PROPDMG*100
 stormdata[stormdata$PROPDMGEXP == "1", ]$PROPDMG<- stormdata[stormdata$PROPDMGEXP == "1",]$PROPDMG*10

Lets take a look at Crop damages exponent

unique(stormdata$CROPDMGEXP)
## [1]   M K m B ? 0 k 2
## Levels:  ? 0 2 B k K m M

Apply the exponent convertion on crop damages, the transformation would be as below

stormdata[stormdata$CROPDMGEXP == "B",]$CROPDMG<- stormdata[stormdata$CROPDMGEXP == "B",]$CROPDMG*1000000000
stormdata[stormdata$CROPDMGEXP == "K"|stormdata$CROPDMGEXP == "k",]$CROPDMG<- stormdata[stormdata$CROPDMGEXP == "K"|stormdata$CROPDMGEXP == "k",]$CROPDMG*1000
stormdata[stormdata$CROPDMGEXP == "M"|stormdata$CROPDMGEXP == "m",]$CROPDMG<- stormdata[stormdata$CROPDMGEXP == "M"|stormdata$CROPDMGEXP == "m",]$CROPDMG*1000000
 stormdata[stormdata$PROPDMGEXP == "2", ]$PROPDMG<- stormdata[stormdata$PROPDMGEXP =="2",]$PROPDMG*100

Lets Summarize the Property Damages by Event types

propdamages<-aggregate(PROPDMG~EVTYPE,stormdata, sum)

Sort it by the most damaged

propdamages<-arrange(propdamages, desc(PROPDMG))

Pick the top 10 events that cause the most damages

propdamagestop <- propdamages[1:10,]
propdamagestop
##               EVTYPE      PROPDMG
## 1              FLOOD 144657709807
## 2  HURRICANE/TYPHOON  69305840000
## 3            TORNADO  56947380677
## 4        STORM SURGE  43323536000
## 5        FLASH FLOOD  16822673979
## 6               HAIL  15735267018
## 7          HURRICANE  11868319010
## 8     TROPICAL STORM   7703890550
## 9       WINTER STORM   6688497251
## 10         HIGH WIND   5270046295

Lets Summarize the Crop damages by Event types

cropdamages<-aggregate(CROPDMG~EVTYPE,stormdata, sum)

Sort it by the most damaged

cropdamages<-arrange(cropdamages, desc(CROPDMG))

Pick the top 10 events that cause the most damages

cropdamagestop<-cropdamages[1:10,]
cropdamagestop
##               EVTYPE     CROPDMG
## 1            DROUGHT 13972566000
## 2              FLOOD  5661968450
## 3        RIVER FLOOD  5029459000
## 4          ICE STORM  5022113500
## 5               HAIL  3025954473
## 6          HURRICANE  2741910000
## 7  HURRICANE/TYPHOON  2607872800
## 8        FLASH FLOOD  1421317100
## 9       EXTREME COLD  1292973000
## 10      FROST/FREEZE  1094086000

Results

Plot the Graph to show the top events that cause the most Fatalities and Injuries

Fatalitiesplot<-ggplot(stormtopFatalities, aes(x=reorder(EVTYPE,-FATALITIES), y=FATALITIES/1000,fill=FATALITIES,label = round(FATALITIES/1000,2 )))+
    geom_bar(stat='identity')+
xlab("Event Type") +
    ylab("Fatalities in Thousands") +
    theme(axis.text.x = element_text(size=7,angle=45, vjust=1, hjust=1))+
    guides(fill=FALSE)+
geom_label (aes(fill = FATALITIES), size=3,colour = "white", fontface = "bold")
Injuriesplot<-ggplot(stormtopInjuries,aes(reorder(EVTYPE,-INJURIES),INJURIES/1000, fill=INJURIES,label = round(INJURIES/1000,2 )))+
    geom_bar(stat='identity')+  xlab("Event Type") +
    ylab("Injuries In Thousands") +
    theme(axis.text.x = element_text(size=7,angle=45, vjust=1, hjust=1))+
guides(fill=FALSE)+
geom_label (aes(fill = INJURIES), size=3,colour = "white", fontface = "bold")

Arrange the plots

grid.arrange(Fatalitiesplot,Injuriesplot,ncol=2, top="Top Harmful Events with respect to population health in Thousands")

From the Graph it shows that Tornado is the most harmful event that causes the most impacts with respect to the population Health

Plot the graph for the top most consequences to Economy

propdamageplot<-ggplot(propdamagestop, aes(x=reorder(EVTYPE,-PROPDMG), y=PROPDMG/1000000000,fill=PROPDMG ,label = round(PROPDMG/1000000000,2 )))+
geom_bar(stat='identity')+
xlab("Event Type") +
ylab("Property Damages in Billions") +
theme(axis.text.x = element_text(size=7,angle=45, vjust=1, hjust=1))+
guides(fill=FALSE)+
geom_label (aes(fill = PROPDMG), size=3,colour = "white", fontface = "bold")
cropdamageplot<-ggplot(cropdamagestop,aes(reorder(EVTYPE,-CROPDMG),CROPDMG/1000000000, fill=CROPDMG,label = round(CROPDMG/1000000000,2 )))+
geom_bar(stat='identity')+  xlab("Event Type") +
ylab("Crop Damages in Billions") +
theme(axis.text.x = element_text(size=7,angle=45, vjust=1, hjust=1))+
guides(fill=FALSE)+
geom_label (aes(fill = CROPDMG), size=3,colour = "white", fontface = "bold")

Arrange the plots

grid.arrange(propdamageplot,cropdamageplot,ncol=2, top=" Top Economic Consequences by Event Types in Billions")

From the graph it is understood that Flood causes the most Property Damages while Drought causes the most Crop Damages.