Title: The Most Lethal, Most Harmful and Most Destructive Climate Events in the United States.

0. Synopsis

This study examines and compare the impacts of differnet events using the date from U.S.National Oceanic and Atmosphere Administration (NOAA). From the perspectives of the lethality and the cost, this study listed and presented the most dangerous natural events. For the most lethal 10 events, the study uses the fatalities and injuries to demonstrate the lethality. For the most costly 10 events, the study uses the damage of properties and damage of crops to demonstrate the economic costs. In sum, tonado, heat, and flood are the most lethal natural disasters in the United States; tornado, TSTM wind, and flood are the events injure most people in the United States;lastly,flood, Typhoon/hurricane and Tornado led to most economic loss in the United States.

1. Preparation

a. Setup Knitr

b. Setup Library

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(reshape2)
library(ggplot2)

c. Download Data

# download process at local: 
'fileUrl <- "https://d396qusza40orc.cloudfront.net/repdata%2Fdata%2FStormData.csv.bz2"
Dest_1 <- "~/JHU_DS4/PeerProject2/repdata-data-StormData.bz2"
download.file(fileUrl, destfile = Dest_1, method = curl)

if(!file.exists(Dest_1)){download.file(FileUrl,destfile = Dest_1, method = "curl")}
if(file.exists(Dest_1)){unzip(Dest_1)}'
## [1] "fileUrl <- \"https://d396qusza40orc.cloudfront.net/repdata%2Fdata%2FStormData.csv.bz2\"\nDest_1 <- \"~/JHU_DS4/PeerProject2/repdata-data-StormData.bz2\"\ndownload.file(fileUrl, destfile = Dest_1, method = curl)\n\nif(!file.exists(Dest_1)){download.file(FileUrl,destfile = Dest_1, method = \"curl\")}\nif(file.exists(Dest_1)){unzip(Dest_1)}"
storm <- read.csv('~/JHU_DS4/PeerProject2/repdata-data-StormData.csv')

d. Examine the Data

str(storm$EVTYPE)
##  Factor w/ 985 levels "   HIGH SURF ADVISORY",..: 834 834 834 834 834 834 834 834 834 834 ...
summary(storm$EVTYPE)
##                     HAIL                TSTM WIND        THUNDERSTORM WIND 
##                   288661                   219940                    82563 
##                  TORNADO              FLASH FLOOD                    FLOOD 
##                    60652                    54277                    25326 
##       THUNDERSTORM WINDS                HIGH WIND                LIGHTNING 
##                    20843                    20212                    15754 
##               HEAVY SNOW               HEAVY RAIN             WINTER STORM 
##                    15708                    11723                    11433 
##           WINTER WEATHER             FUNNEL CLOUD         MARINE TSTM WIND 
##                     7026                     6839                     6175 
## MARINE THUNDERSTORM WIND               WATERSPOUT              STRONG WIND 
##                     5812                     3796                     3566 
##     URBAN/SML STREAM FLD                 WILDFIRE                 BLIZZARD 
##                     3392                     2761                     2719 
##                  DROUGHT                ICE STORM           EXCESSIVE HEAT 
##                     2488                     2006                     1678 
##               HIGH WINDS         WILD/FOREST FIRE             FROST/FREEZE 
##                     1533                     1457                     1342 
##                DENSE FOG       WINTER WEATHER/MIX           TSTM WIND/HAIL 
##                     1293                     1104                     1028 
##  EXTREME COLD/WIND CHILL                     HEAT                HIGH SURF 
##                     1002                      767                      725 
##           TROPICAL STORM           FLASH FLOODING             EXTREME COLD 
##                      690                      682                      655 
##            COASTAL FLOOD         LAKE-EFFECT SNOW        FLOOD/FLASH FLOOD 
##                      650                      636                      624 
##                LANDSLIDE                     SNOW          COLD/WIND CHILL 
##                      600                      587                      539 
##                      FOG              RIP CURRENT              MARINE HAIL 
##                      538                      470                      442 
##               DUST STORM                AVALANCHE                     WIND 
##                      427                      386                      340 
##             RIP CURRENTS              STORM SURGE            FREEZING RAIN 
##                      304                      261                      250 
##              URBAN FLOOD     HEAVY SURF/HIGH SURF        EXTREME WINDCHILL 
##                      249                      228                      204 
##             STRONG WINDS           DRY MICROBURST    ASTRONOMICAL LOW TIDE 
##                      196                      186                      174 
##                HURRICANE              RIVER FLOOD               LIGHT SNOW 
##                      174                      173                      154 
##         STORM SURGE/TIDE            RECORD WARMTH         COASTAL FLOODING 
##                      148                      146                      143 
##               DUST DEVIL         MARINE HIGH WIND        UNSEASONABLY WARM 
##                      141                      135                      126 
##                 FLOODING   ASTRONOMICAL HIGH TIDE        MODERATE SNOWFALL 
##                      120                      103                      101 
##           URBAN FLOODING               WINTRY MIX        HURRICANE/TYPHOON 
##                       98                       90                       88 
##            FUNNEL CLOUDS               HEAVY SURF              RECORD HEAT 
##                       87                       84                       81 
##                   FREEZE                HEAT WAVE                     COLD 
##                       74                       74                       72 
##              RECORD COLD                      ICE  THUNDERSTORM WINDS HAIL 
##                       64                       61                       61 
##      TROPICAL DEPRESSION                    SLEET         UNSEASONABLY DRY 
##                       60                       59                       56 
##                    FROST              GUSTY WINDS      THUNDERSTORM WINDSS 
##                       53                       53                       51 
##       MARINE STRONG WIND                    OTHER               SMALL HAIL 
##                       48                       48                       47 
##                   FUNNEL             FREEZING FOG             THUNDERSTORM 
##                       46                       45                       45 
##       Temperature record          TSTM WIND (G45)         Coastal Flooding 
##                       43                       39                       38 
##              WATERSPOUTS    MONTHLY PRECIPITATION                    WINDS 
##                       37                       36                       36 
##                  (Other) 
##                     2940
df_storm <- data.frame(summary(storm$EVTYPE))

2. Process Data

Meanwhile, it is necessary to take out the unrelated factors in this case. After examining the assignment’s questions, the following factors are extracted: Event Fatilities INJURIES PROPDMG PROPDMGEXP CROPDMG CROPDMGEXP After this extraction, ab_storm is prepared for the further analysis.

ab_storm <- data.frame(storm$EVTYPE, storm$FATALITIES,storm$INJURIES,storm$PROPDMG, storm$PROPDMGEXP, storm$CROPDMG, storm$CROPDMGEXP)

Examing the data again to see whether there is any mistake in the variables. Then, in the PROPDMGEXP and CROPDMGEXP, we found that these two parts provides the unit or the exponent of the PROPDMG and CROPDMG, the variables that vital to our analysis.

## NULL

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

a. Analysis

Let us aggregate these data into different categories

Fatality_rate <- aggregate(ab_storm$storm.FATALITIES ~ ab_storm$storm.EVTYPE, FUN = sum, rm.na = TRUE)
Injuries_rate <- aggregate(ab_storm$storm.INJURIES ~ ab_storm$storm.EVTYPE, FUN = sum, rm.na = TRUE)

By Aggregating the data into two groups and combining them under the dataframe of lifecost, we are able to use plots to demonstrate the possible answers to this question. Lets us recognize 10 type of events leading to the most fatalities and injuries.

b. Plots

Based on the conditions, we are making two plots side by side.

fatal10 <- Fatality_rate[order(-Fatality_rate$`ab_storm$storm.FATALITIES`), ][1:10, ]

Injuries10 <- Injuries_rate[order(-Injuries_rate$`ab_storm$storm.INJURIES`), ][1:10, ]

The most lethal disaster event is Tornado based on the fatalities.

fatal10
##     ab_storm$storm.EVTYPE ab_storm$storm.FATALITIES
## 834               TORNADO                      5634
## 130        EXCESSIVE HEAT                      1904
## 153           FLASH FLOOD                       979
## 275                  HEAT                       938
## 464             LIGHTNING                       817
## 856             TSTM WIND                       505
## 170                 FLOOD                       471
## 585           RIP CURRENT                       369
## 359             HIGH WIND                       249
## 19              AVALANCHE                       225
#Fatalities
fatality<-ggplot(fatal10, aes(x=reorder(`ab_storm$storm.EVTYPE`, -`ab_storm$storm.FATALITIES`), y= `ab_storm$storm.FATALITIES`))+ geom_bar(stat="identity", fill = 'Maroon', color = 'Maroon') + theme(axis.text.x = element_text(angle=90, vjust=0.5, hjust=1))+ggtitle("Top 10 Events Led to Most Fatalities") +labs(x="EVENT TYPE", y="Total Fatality")
fatality

Based on the plot, we can detect that in both categories, the Tonado is the most destructive disaster, which kills most people and hurts most citizens in the United States.

#Injuries
Injuries10
##     ab_storm$storm.EVTYPE ab_storm$storm.INJURIES
## 834               TORNADO                   91347
## 856             TSTM WIND                    6958
## 170                 FLOOD                    6790
## 130        EXCESSIVE HEAT                    6526
## 464             LIGHTNING                    5231
## 275                  HEAT                    2101
## 427             ICE STORM                    1976
## 153           FLASH FLOOD                    1778
## 760     THUNDERSTORM WIND                    1489
## 244                  HAIL                    1362
injuries<- ggplot(Injuries10, aes(x=reorder(`ab_storm$storm.EVTYPE`, -`ab_storm$storm.INJURIES`), y= `ab_storm$storm.INJURIES`))+ geom_bar(stat="identity",fill = 'Orange', color = 'Orange') + theme(axis.text.x = element_text(angle=90, vjust=0.5, hjust=1))+ggtitle("Top 10 Events Led to Most Injuries") +labs(x="EVENT TYPE", y="Total Injuries")
injuries

Based on the plot, we can detect that in both categories, the Tonado is the most destructive disaster, which kills most people and hurts most citizens in the United States.

c. Result

Based on the data frame and plots, we can detect that in both categories, the Tonado is the most destructive disaster, which kills most people and hurts most citizens in the United States.

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

a. Analysis

For question 2, here two major variables that we are dealing with are the destruction over the properties and crops, which could be find in the PROPDMG and CROPDMG. Similar to the previous example, I will use the graph and table to compile the two costs side by side.

Using the value of the property damage (PDMG) and crop damagae (CDMG), I can compare and test.

b. Plots

library(ggplot2)
# Selecting 10 events cause most Property Damage 
econ_storm <- ab_storm[,c(1,9,11)]
econ_storm$EDMG <- econ_storm$PDMG + econ_storm$CDMG

EDMG_a <- aggregate(econ_storm$EDMG ~ econ_storm$storm.EVTYPE, FUN = sum)

EDMG10 <- EDMG_a[order(-EDMG_a$`econ_storm$EDMG`), ][1:10,]


# Plot
edmg<-ggplot(EDMG10, aes(x=reorder(`econ_storm$storm.EVTYPE`, -`econ_storm$EDMG`), y= `econ_storm$EDMG`))+ geom_bar(stat="identity") + theme(axis.text.x = element_text(angle=90, vjust=0.5, hjust=1))+ggtitle("Top 10 Events Caused Most Economic Damage of Properties and Crops") +labs(x="EVENT TYPE", y="Total Economic Loss")

edmg

c. Result

Based on the result, it can be tell that the flood, hurricane and Tornada are the most economical destructive events happened in the United States.

5. Summary

Based on the data of NOAA, after comparing the economic damage and life costs, the tornado/typhoon/hurricane remain as the most deadly and destructive events that happening in the United States, which fits the expectation and history. Hence, the governors, government staffs, and scientists should continue establish advance climate systems for detecting, preventing and relieving the impacts of these extreme weathers.