Synopsis

This report analyzes the consequences of severe weather events in the United States, focusing on their impacts on population health and the economy. Using data from the NOAA Storm Database, we identify the most harmful storm types in terms of fatalities, injuries, property damage, and crop damage. The findings aim to inform disaster preparedness and mitigation strategies to reduce the adverse effects of severe weather events.

Data Processing

The dataset used in this analysis is sourced from the NOAA Storm Database, which contains detailed information about severe weather events in the United States. It includes data on event types, dates, locations, and associated consequences such as fatalities, injuries, and property damage. The dataset spans several decades, providing a comprehensive view of storm impacts over time. This rich dataset enables us to identify patterns and trends, assess the severity of different storm types, and evaluate their effects on public health and the economy. However, it is important to note that the dataset may have limitations, such as inconsistencies in event reporting and missing values, which are addressed during the data preprocessing stage.

# Load necessary libraries
library(dplyr)

# Decompress and load the data
file_path <- "repdata_data_StormData1.csv"
data <- read.csv(file_path)

# View summary of the data
summary(data)
##     STATE__       BGN_DATE           BGN_TIME          TIME_ZONE        
##  Min.   : 1.0   Length:902297      Length:902297      Length:902297     
##  1st Qu.:19.0   Class :character   Class :character   Class :character  
##  Median :30.0   Mode  :character   Mode  :character   Mode  :character  
##  Mean   :31.2                                                           
##  3rd Qu.:45.0                                                           
##  Max.   :95.0                                                           
##                                                                         
##      COUNTY       COUNTYNAME           STATE              EVTYPE         
##  Min.   :  0.0   Length:902297      Length:902297      Length:902297     
##  1st Qu.: 31.0   Class :character   Class :character   Class :character  
##  Median : 75.0   Mode  :character   Mode  :character   Mode  :character  
##  Mean   :100.6                                                           
##  3rd Qu.:131.0                                                           
##  Max.   :873.0                                                           
##                                                                          
##    BGN_RANGE          BGN_AZI           BGN_LOCATI          END_DATE        
##  Min.   :   0.000   Length:902297      Length:902297      Length:902297     
##  1st Qu.:   0.000   Class :character   Class :character   Class :character  
##  Median :   0.000   Mode  :character   Mode  :character   Mode  :character  
##  Mean   :   1.484                                                           
##  3rd Qu.:   1.000                                                           
##  Max.   :3749.000                                                           
##                                                                             
##    END_TIME           COUNTY_END COUNTYENDN       END_RANGE       
##  Length:902297      Min.   :0    Mode:logical   Min.   :  0.0000  
##  Class :character   1st Qu.:0    NA's:902297    1st Qu.:  0.0000  
##  Mode  :character   Median :0                   Median :  0.0000  
##                     Mean   :0                   Mean   :  0.9862  
##                     3rd Qu.:0                   3rd Qu.:  0.0000  
##                     Max.   :0                   Max.   :925.0000  
##                                                                   
##    END_AZI           END_LOCATI            LENGTH              WIDTH         
##  Length:902297      Length:902297      Min.   :   0.0000   Min.   :   0.000  
##  Class :character   Class :character   1st Qu.:   0.0000   1st Qu.:   0.000  
##  Mode  :character   Mode  :character   Median :   0.0000   Median :   0.000  
##                                        Mean   :   0.2301   Mean   :   7.503  
##                                        3rd Qu.:   0.0000   3rd Qu.:   0.000  
##                                        Max.   :2315.0000   Max.   :4400.000  
##                                                                              
##        F               MAG            FATALITIES          INJURIES        
##  Min.   :0.0      Min.   :    0.0   Min.   :  0.0000   Min.   :   0.0000  
##  1st Qu.:0.0      1st Qu.:    0.0   1st Qu.:  0.0000   1st Qu.:   0.0000  
##  Median :1.0      Median :   50.0   Median :  0.0000   Median :   0.0000  
##  Mean   :0.9      Mean   :   46.9   Mean   :  0.0168   Mean   :   0.1557  
##  3rd Qu.:1.0      3rd Qu.:   75.0   3rd Qu.:  0.0000   3rd Qu.:   0.0000  
##  Max.   :5.0      Max.   :22000.0   Max.   :583.0000   Max.   :1700.0000  
##  NA's   :843563                                                           
##     PROPDMG         PROPDMGEXP           CROPDMG         CROPDMGEXP       
##  Min.   :   0.00   Length:902297      Min.   :  0.000   Length:902297     
##  1st Qu.:   0.00   Class :character   1st Qu.:  0.000   Class :character  
##  Median :   0.00   Mode  :character   Median :  0.000   Mode  :character  
##  Mean   :  12.06                      Mean   :  1.527                     
##  3rd Qu.:   0.50                      3rd Qu.:  0.000                     
##  Max.   :5000.00                      Max.   :990.000                     
##                                                                           
##      WFO             STATEOFFIC         ZONENAMES            LATITUDE   
##  Length:902297      Length:902297      Length:902297      Min.   :   0  
##  Class :character   Class :character   Class :character   1st Qu.:2802  
##  Mode  :character   Mode  :character   Mode  :character   Median :3540  
##                                                           Mean   :2875  
##                                                           3rd Qu.:4019  
##                                                           Max.   :9706  
##                                                           NA's   :47    
##    LONGITUDE        LATITUDE_E     LONGITUDE_       REMARKS         
##  Min.   :-14451   Min.   :   0   Min.   :-14455   Length:902297     
##  1st Qu.:  7247   1st Qu.:   0   1st Qu.:     0   Class :character  
##  Median :  8707   Median :   0   Median :     0   Mode  :character  
##  Mean   :  6940   Mean   :1452   Mean   :  3509                     
##  3rd Qu.:  9605   3rd Qu.:3549   3rd Qu.:  8735                     
##  Max.   : 17124   Max.   :9706   Max.   :106220                     
##                   NA's   :40                                        
##      REFNUM      
##  Min.   :     1  
##  1st Qu.:225575  
##  Median :451149  
##  Mean   :451149  
##  3rd Qu.:676723  
##  Max.   :902297  
## 
# Display structure of the data
str(data)
## 'data.frame':    902297 obs. of  37 variables:
##  $ STATE__   : num  1 1 1 1 1 1 1 1 1 1 ...
##  $ BGN_DATE  : chr  "4/18/1950 0:00:00" "4/18/1950 0:00:00" "2/20/1951 0:00:00" "6/8/1951 0:00:00" ...
##  $ BGN_TIME  : chr  "0130" "0145" "1600" "0900" ...
##  $ TIME_ZONE : chr  "CST" "CST" "CST" "CST" ...
##  $ COUNTY    : num  97 3 57 89 43 77 9 123 125 57 ...
##  $ COUNTYNAME: chr  "MOBILE" "BALDWIN" "FAYETTE" "MADISON" ...
##  $ STATE     : chr  "AL" "AL" "AL" "AL" ...
##  $ EVTYPE    : chr  "TORNADO" "TORNADO" "TORNADO" "TORNADO" ...
##  $ BGN_RANGE : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ BGN_AZI   : chr  "" "" "" "" ...
##  $ BGN_LOCATI: chr  "" "" "" "" ...
##  $ END_DATE  : chr  "" "" "" "" ...
##  $ END_TIME  : chr  "" "" "" "" ...
##  $ 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   : chr  "" "" "" "" ...
##  $ END_LOCATI: chr  "" "" "" "" ...
##  $ 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: chr  "K" "K" "K" "K" ...
##  $ CROPDMG   : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ CROPDMGEXP: chr  "" "" "" "" ...
##  $ WFO       : chr  "" "" "" "" ...
##  $ STATEOFFIC: chr  "" "" "" "" ...
##  $ ZONENAMES : chr  "" "" "" "" ...
##  $ 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   : chr  "" "" "" "" ...
##  $ REFNUM    : num  1 2 3 4 5 6 7 8 9 10 ...

Results

Population Health Consequences

Population health is the most important aspect of storm consequences, as it directly affects the well-being of individuals and communities. There are many factors that contribute to the impact of storms on population health, including fatalities and injuries. In this section, we will analyze the data to identify the most harmful storm types in terms of their effects on public health.

library(dplyr)
# Summarize fatalities and injuries by event type
health_data <- data %>%
  group_by(EVTYPE) %>%
  summarise(
    total_fatalities = sum(FATALITIES, na.rm = TRUE),
    total_injuries = sum(INJURIES, na.rm = TRUE)
  ) %>%
  arrange(desc(total_fatalities + total_injuries))
# Display top 10 event types harmful to population health
head(health_data, 10)
## # A tibble: 10 x 3
##    EVTYPE            total_fatalities total_injuries
##    <chr>                        <dbl>          <dbl>
##  1 TORNADO                       5633          91346
##  2 EXCESSIVE HEAT                1903           6525
##  3 TSTM WIND                      504           6957
##  4 FLOOD                          470           6789
##  5 LIGHTNING                      816           5230
##  6 HEAT                           937           2100
##  7 FLASH FLOOD                    978           1777
##  8 ICE STORM                       89           1975
##  9 THUNDERSTORM WIND              133           1488
## 10 WINTER STORM                   206           1321
# Plotting the top 10 event types harmful to population health
library(ggplot2)
ggplot(
    health_data[1:10, ], 
    aes(
        x = reorder(EVTYPE, total_fatalities + total_injuries), 
        y = total_fatalities + total_injuries
    )
) +
  geom_bar(stat = "identity", fill = "steelblue") +
  labs(title = "Top 10 Event Types Harmful to Population Health",
       x = "Event Type",
       y = "Total Fatalities and Injuries") +
  theme_minimal() +
  coord_flip()

As the results show, tornadoes are the most harmful storm type in terms of population health, causing the highest number of fatalities and injuries. Other significant storm types include excessive heat, tstm wind, and flood. These findings highlight the need for targeted interventions and preparedness measures to mitigate the impacts of these severe weather events on public health.

Economic Consequences

In the other hand, economic consequences of storms are also significant, as they can lead to substantial financial losses for individuals, businesses, and governments. The economic impact of storms can be measured in terms of property damage and crop damage. In this section, we will analyze the data to identify the storm types that cause the most economic damage.

library(dplyr)
# Summarize property and crop damage by event type
economic_data <- data %>%
  group_by(EVTYPE) %>%
  summarise(
    total_property_damage = sum(PROPDMG, na.rm = TRUE),
    total_crop_damage = sum(CROPDMG, na.rm = TRUE)
  ) %>%
  arrange(desc(total_property_damage + total_crop_damage))
# Display top 10 event types causing economic damage
head(economic_data, 10)
## # A tibble: 10 x 3
##    EVTYPE             total_property_damage total_crop_damage
##    <chr>                              <dbl>             <dbl>
##  1 TORNADO                         3212258.           100019.
##  2 FLASH FLOOD                     1420125.           179200.
##  3 TSTM WIND                       1335966.           109203.
##  4 HAIL                             688693.           579596.
##  5 FLOOD                            899938.           168038.
##  6 THUNDERSTORM WIND                876844.            66791.
##  7 LIGHTNING                        603352.             3581.
##  8 THUNDERSTORM WINDS               446293.            18685.
##  9 HIGH WIND                        324732.            17283.
## 10 WINTER STORM                     132721.             1979.
# Plotting the top 10 event types causing economic damage
library(scales)

ggplot(
    economic_data[1:10, ], 
    aes(
        x = reorder(EVTYPE, total_property_damage + total_crop_damage), 
        y = total_property_damage + total_crop_damage
    )
) +
  geom_bar(stat = "identity", fill = "darkgreen") +
  labs(title = "Top 10 Event Types Causing Economic Damage",
       x = "Event Type",
       y = "Total Property and Crop Damage") +
  scale_y_continuous(labels = scales::label_number_si()) +
  theme_minimal() +
  coord_flip()

The results indicate that the most economically damaging storm type is same as the most harmful to population health, which is tornadoes. However, flash flood and tstm wind also contribute significantly to economic losses. These findings underscore the importance of disaster preparedness and resource allocation to minimize the economic impacts of severe weather events.