NOAA Storm Database Analysis

Synopsis

This report analyzes the U.S. National Oceanic and Atmospheric Administration (NOAA) storm database. The objective is to determine which weather events are most harmful to population health and which weather events have the greatest economic consequences across the United States. Population health impact is measured using fatalities and injuries, while economic impact is measured using property and crop damage.

Data Processing

storm <- read.csv("repdata_data_StormData.csv.bz2")

Health Impact Analysis

storm$HealthDamage <- storm$FATALITIES + storm$INJURIES

health <- aggregate(HealthDamage ~ EVTYPE,
                    data = storm,
                    sum)

health <- health[order(-health$HealthDamage), ]

topHealth <- head(health, 10)

topHealth

##                EVTYPE HealthDamage
## 834           TORNADO        96979
## 130    EXCESSIVE HEAT         8428
## 856         TSTM WIND         7461
## 170             FLOOD         7259
## 464         LIGHTNING         6046
## 275              HEAT         3037
## 153       FLASH FLOOD         2755
## 427         ICE STORM         2064
## 760 THUNDERSTORM WIND         1621
## 972      WINTER STORM         1527

Economic Impact Analysis

storm$EconomicDamage <- storm$PROPDMG + storm$CROPDMG

economic <- aggregate(EconomicDamage ~ EVTYPE,
                      data = storm,
                      sum)

economic <- economic[order(-economic$EconomicDamage), ]

topEconomic <- head(economic, 10)

topEconomic

##                 EVTYPE EconomicDamage
## 834            TORNADO      3312276.7
## 153        FLASH FLOOD      1599325.1
## 856          TSTM WIND      1445168.2
## 244               HAIL      1268289.7
## 170              FLOOD      1067976.4
## 760  THUNDERSTORM WIND       943635.6
## 464          LIGHTNING       606932.4
## 786 THUNDERSTORM WINDS       464978.1
## 359          HIGH WIND       342014.8
## 972       WINTER STORM       134699.6

Results

Events Most Harmful to Population Health

barplot(topHealth$HealthDamage,
        names.arg = topHealth$EVTYPE,
        las = 2,
        col = "red",
        main = "Top 10 Weather Events Harmful to Population Health",
        ylab = "Fatalities + Injuries")

Interpretation

The figure shows that tornado-related events are among the most harmful weather events with respect to population health. The ranking is based on the combined total of fatalities and injuries.

Events with Greatest Economic Consequences

barplot(topEconomic$EconomicDamage,
        names.arg = topEconomic$EVTYPE,
        las = 2,
        col = "blue",
        main = "Top 10 Weather Events with Greatest Economic Consequences",
        ylab = "Property Damage + Crop Damage")

Interpretation

The figure shows the weather event types responsible for the greatest economic losses. Floods, storms, and other major weather disasters account for the largest property and crop damage totals.

Conclusion

This analysis of the NOAA Storm Database indicates that several severe weather event types have major impacts on population health and economic outcomes. Tornadoes contribute heavily to fatalities and injuries, while flood and storm-related events contribute significantly to economic damage.

Events Most Harmful to Population Health

The event type that causes the greatest harm to population health is Tornado. Tornadoes account for the highest combined total of fatalities and injuries across the United States.

Events with Greatest Economic Consequences

Tornadoes cause the greatest overall economic damage, followed by flash floods, thunderstorms, hail, and floods. These events account for the largest combined property and crop damage totals.