Analysis of NOAA Storm Database: impact of severe weather events on U.S. public health and economics

L.M. 15-10-2024

Synopsis

Storms and other severe weather events can cause both public health and economic problems for communities and municipalities.

This project involves exploring the U.S. National Oceanic and Atmospheric Administration’s (NOAA) storm database, which 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.

In particularly, we are going to address which types of events are most harmful with respect to population health and which types of events have the greatest economic consequences across the United States.

Data processing

Loading, visualising and selecting the data

data <- read.csv("repdata_data_StormData.csv", 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

We identify the names of the column to be able to select the relevant ones with the dplyr package for further analysis

colnames(data)
##  [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"
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
sub_data <-  data%>% select (EVTYPE, FATALITIES, INJURIES, contains("DMG"))
head(sub_data)
##    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

Results

Which types of events are the most harmful with respect to population health?

We calculate the sum of the fatalities and injuries caused by each event and the total sum. We then arrange the data based on the most harmful events for the population health. We finally select the top 10.

sub_data2 <-  sub_data %>% group_by(EVTYPE) %>% summarize(Tot_fat= sum(FATALITIES), Tot_inj= sum(INJURIES), TOT= sum(FATALITIES, INJURIES)) %>% filter(Tot_fat > 0 |Tot_inj > 0 | TOT> 0 ) %>% arrange(desc(TOT))
head(sub_data2)
## # A tibble: 6 × 4
##   EVTYPE         Tot_fat Tot_inj   TOT
##   <chr>            <dbl>   <dbl> <dbl>
## 1 TORNADO           5633   91346 96979
## 2 EXCESSIVE HEAT    1903    6525  8428
## 3 TSTM WIND          504    6957  7461
## 4 FLOOD              470    6789  7259
## 5 LIGHTNING          816    5230  6046
## 6 HEAT               937    2100  3037
sub_data2 <- sub_data2[, c("EVTYPE", "TOT", "Tot_inj", "Tot_fat")]
head(sub_data2)
## # A tibble: 6 × 4
##   EVTYPE           TOT Tot_inj Tot_fat
##   <chr>          <dbl>   <dbl>   <dbl>
## 1 TORNADO        96979   91346    5633
## 2 EXCESSIVE HEAT  8428    6525    1903
## 3 TSTM WIND       7461    6957     504
## 4 FLOOD           7259    6789     470
## 5 LIGHTNING       6046    5230     816
## 6 HEAT            3037    2100     937
TOP10_ph <- sub_data2[1:10, ]
TOP10_ph
## # A tibble: 10 × 4
##    EVTYPE              TOT Tot_inj Tot_fat
##    <chr>             <dbl>   <dbl>   <dbl>
##  1 TORNADO           96979   91346    5633
##  2 EXCESSIVE HEAT     8428    6525    1903
##  3 TSTM WIND          7461    6957     504
##  4 FLOOD              7259    6789     470
##  5 LIGHTNING          6046    5230     816
##  6 HEAT               3037    2100     937
##  7 FLASH FLOOD        2755    1777     978
##  8 ICE STORM          2064    1975      89
##  9 THUNDERSTORM WIND  1621    1488     133
## 10 WINTER STORM       1527    1321     206

First we use the package “reshape2” to assign the columns to variables. Then, we plot the ten most harmful events for the population health. The barplot is created with ggplot2 package and includes the total fatalities, the total injuries and the sum of those (TOT)

library(ggplot2)
library(RColorBrewer)
library(reshape2)

public_health<- melt(TOP10_ph, id.vars = "EVTYPE")

BP <- ggplot(public_health, aes(reorder(EVTYPE, -value), value, fill = variable))
BP + geom_bar(stat = "identity", position = "dodge") + labs(x = "Event Type", y = "Harmful Event Counts", title = "Top 10 Harmful Events for Population Health") +  scale_fill_brewer(palette = "Accent") + theme_light() + theme(axis.text.x = element_text(angle = 90, vjust = 0.5))

Which types of events have the greatest economic consequences?

We analyse the total property damage and total crop damage separately. We calculate the total damage and then we merge the results by event type. We rearrange the columns and select the TOP 10.

PROP.STORM_1 <-  sub_data%>% select(EVTYPE, starts_with("PROP")) %>% group_by(EVTYPE, PROPDMGEXP) %>% summarize(DAMAGE=sum(PROPDMG))
## `summarise()` has grouped output by 'EVTYPE'. You can override using the
## `.groups` argument.
PROP.STORM_2 <- PROP.STORM_1 %>%  mutate(PROP_DAMAGE= ifelse(PROPDMGEXP=="K", DAMAGE*(10^3), ifelse(PROPDMGEXP=="M", DAMAGE*(10^6), ifelse(PROPDMGEXP=="B", DAMAGE*(10^9), DAMAGE))))

PROP_STORM <- summarise(PROP.STORM_2, TOT_PROP_DMG= sum(PROP_DAMAGE))

CROP.STORM_1 <-  sub_data%>% select(EVTYPE, starts_with("CROP")) %>% group_by(EVTYPE, CROPDMGEXP) %>% summarize(DAMAGE=sum(CROPDMG))
## `summarise()` has grouped output by 'EVTYPE'. You can override using the
## `.groups` argument.
CROP.STORM_2 <- CROP.STORM_1 %>%  mutate(CROP_DAMAGE= ifelse(CROPDMGEXP=="K", DAMAGE*(10^3), ifelse(CROPDMGEXP=="M", DAMAGE*(10^6), ifelse(CROPDMGEXP=="B", DAMAGE*(10^9), DAMAGE))))

CROP_STORM <- summarise(CROP.STORM_2, TOT_CROP_DMG= sum(CROP_DAMAGE))

Eco_damage <- merge(PROP_STORM, CROP_STORM, by= "EVTYPE")
Eco_damage_TOT <- Eco_damage %>% group_by(EVTYPE) %>% summarize(TOT_ECO= sum(TOT_PROP_DMG, TOT_CROP_DMG))
Economic_Cons <- merge(Eco_damage, Eco_damage_TOT, by= "EVTYPE")

Economic_Cons <- Economic_Cons[, c("EVTYPE", "TOT_ECO", "TOT_PROP_DMG", "TOT_CROP_DMG")]
Economic_Cons <- arrange(Economic_Cons, desc(TOT_ECO))
TOP10_ec <- Economic_Cons[1:10, ]

First we use the package “reshape2” to assign the columns to variables. Then, we plot the ten events that have the greatest economic consequences. The barplot is created with ggplot2 package and includes the total property damages (TOT_PROP_DMG), the total crop damages (TOT_CROP_DMG) and the sum of those (TOT_ECO)

library(ggplot2)
library(RColorBrewer)
library(reshape2)
 
economic_consequences<- melt(TOP10_ec, id.vars = "EVTYPE")
 
EC <- ggplot(economic_consequences, aes(reorder(EVTYPE, -value), value, fill = variable))
EC + geom_bar(stat = "identity", position = "dodge") + labs(x = "Event Type", y = "Event Counts", title = "Top 10 Events for Economic Consequences") +  scale_fill_brewer(palette = "Set2") + theme_light() + theme(axis.text.x = element_text(angle = 90, vjust = 0.5))

Conclusions

From the analysis above, Tornado results as the most harmful event for population health, while Flood results as the worst event in terms of economic consequences.