#Synopsis In this project, we investigate the effect of many different types weather events on resulting population health (through injuries and fatalities) and on the economy (through property damage and crop damage). We found that tornados are the most harmful weather event in terms of both injuries and fatalities. Hurricanes had the greatest economic consequences in terms of property damage and crop damage. The method of how this information was acquired is shown below along with some helpful figures.

Loading Libraries and Data + Tidying Data

We first load all useful libraries, the data, and subset based on population health and economic consequences.

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(ggplot2)
stormdata <- read.csv("repdata_data_StormData.csv")
tidySD <- stormdata[,c('EVTYPE','FATALITIES','INJURIES', 'PROPDMG', 'PROPDMGEXP', 'CROPDMG', 'CROPDMGEXP')] #population damage and economic consequences

Population Health

Aggregating and Ordering Data

x <- as.data.frame(aggregate(INJURIES ~ EVTYPE,tidySD,sum)) 
y <- as.data.frame(aggregate(FATALITIES ~ EVTYPE, tidySD, sum))

x <- x %>% arrange(desc(x$INJURIES)) %>% mutate(EVTYPE=factor(EVTYPE, levels=EVTYPE))
y <- y %>% arrange(desc(y$FATALITIES)) %>% mutate(EVTYPE=factor(EVTYPE, levels=EVTYPE))

Plots

Here we plot both top ten event types resulting in the highest injuries and fatalities.

#top ten observations for plotting
ggplot(x[1:10,],aes(x=EVTYPE,y=INJURIES)) + geom_bar(stat="identity", fill= " light pink") + theme(axis.text.x = element_text(angle = 90, hjust=1)) 

ggplot(y[1:10,],aes(x=EVTYPE,y=FATALITIES)) + geom_bar(stat="identity", fill= " light green") + theme(axis.text.x = element_text(angle = 90, hjust=1))

Economic Consequences

Processing Data

Processing data such that the property damage and crop damage value have the exponents accounted for.

tidySD[tidySD$PROPDMGEXP == "H", ]$PROPDMG <- tidySD[tidySD$PROPDMGEXP == "H", ]$PROPDMG * 100
tidySD[tidySD$PROPDMGEXP == "K", ]$PROPDMG <- tidySD[tidySD$PROPDMGEXP == "K", ]$PROPDMG * 1000
tidySD[tidySD$PROPDMGEXP == "M", ]$PROPDMG <- tidySD[tidySD$PROPDMGEXP == "M", ]$PROPDMG * 10^6
tidySD[tidySD$PROPDMGEXP == "B", ]$PROPDMG <- tidySD[tidySD$PROPDMGEXP == "B", ]$PROPDMG * 10^9

tidySD[tidySD$CROPDMGEXP == "H", ]$PROPDMG <- tidySD[tidySD$CROPDMGEXP == "H", ]$CROPDMG * 100
tidySD[tidySD$CROPDMGEXP == "K", ]$PROPDMG <- tidySD[tidySD$CROPDMGEXP == "K", ]$CROPDMG * 10^3
tidySD[tidySD$CROPDMGEXP == "M", ]$PROPDMG <- tidySD[tidySD$CROPDMGEXP == "M", ]$CROPDMG * 10^6
tidySD[tidySD$CROPDMGEXP == "B", ]$PROPDMG <- tidySD[tidySD$CROPDMGEXP == "B", ]$CROPDMG * 10^9

Aggregating and Ordering Data

a <- as.data.frame(aggregate(PROPDMG ~ EVTYPE,tidySD,sum))
b <- as.data.frame(aggregate(CROPDMG ~ EVTYPE, tidySD, sum))

totaldamages <- merge(a,b, by = intersect(names(a),names(b)))
totaldamages <- totaldamages %>% mutate(Total = PROPDMG + CROPDMG) %>% arrange(desc(Total)) %>% mutate(EVTYPE=factor(EVTYPE, levels=EVTYPE))

Plotting total damages based on event type.

ggplot(totaldamages[1:10,],aes(x=EVTYPE,y=Total)) + geom_bar(stat="identity", fill= " light pink") + theme(axis.text.x = element_text(angle = 90, hjust=1))

Results

Quick view on top five events for public health and economic effects.

head(x)
##           EVTYPE INJURIES
## 1        TORNADO    91346
## 2      TSTM WIND     6957
## 3          FLOOD     6789
## 4 EXCESSIVE HEAT     6525
## 5      LIGHTNING     5230
## 6           HEAT     2100
head(y)
##           EVTYPE FATALITIES
## 1        TORNADO       5633
## 2 EXCESSIVE HEAT       1903
## 3    FLASH FLOOD        978
## 4           HEAT        937
## 5      LIGHTNING        816
## 6      TSTM WIND        504
head(totaldamages)
##              EVTYPE     PROPDMG   CROPDMG       Total
## 1 HURRICANE/TYPHOON 45173417800   4798.48 45173422598
## 2       STORM SURGE 43320626000      5.00 43320626005
## 3           TORNADO 41173842157 100018.52 41173942176
## 4             FLOOD 17483189207 168037.88 17483357245
## 5           DROUGHT 14784951000  33898.62 14784984899
## 6              HAIL 10761317275 579596.28 10761896871