Synopsis:

In this report we show the analysis we have done on the NOAA data base 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.

We have mainly focused on two aspects:

To do this, we have worked with a data file that contains all the information of weather events along over 60 years, from 1950 to 2011.

After a first reading and processing the file, we perform data analysis to respond the issues raised, providing all the explanations, tables, figures and conclusions.

Prepare the Enviroment

First, we are go to load the necesary libraries and prepare the enviroment to use Knit option.

library(plyr)
library(ggplot2)
library(knitr)
opts_chunk$set(echo = TRUE, results = 'hold')
library(gridExtra)
## Loading required package: grid

Data Proccessing.

Population Health

Now we go to download and read the file

if (!file.exists("./noaa")){ 
        dir.create("./noaa")
        url <- "http://d396qusza40orc.cloudfront.net/repdata%2Fdata%2FStormData.csv.bz2"
download.file(url,destfile="./noaa/stormdata.csv.bz2",method="curl")
}

storm <- read.csv(bzfile("./noaa/stormdata.csv.bz2"))
str(storm)
## 'data.frame':    902297 obs. of  37 variables:
##  $ STATE__   : num  1 1 1 1 1 1 1 1 1 1 ...
##  $ BGN_DATE  : Factor w/ 16335 levels "1/1/1966 0:00:00",..: 6523 6523 4242 11116 2224 2224 2260 383 3980 3980 ...
##  $ BGN_TIME  : Factor w/ 3608 levels "000","0000","0001",..: 152 167 2645 1563 2524 3126 122 1563 3126 3126 ...
##  $ TIME_ZONE : Factor w/ 22 levels "ADT","AKS","AST",..: 6 6 6 6 6 6 6 6 6 6 ...
##  $ COUNTY    : num  97 3 57 89 43 77 9 123 125 57 ...
##  $ COUNTYNAME: Factor w/ 29601 levels "","5NM E OF MACKINAC BRIDGE TO PRESQUE ISLE LT MI",..: 13513 1873 4598 10592 4372 10094 1973 23873 24418 4598 ...
##  $ STATE     : Factor w/ 72 levels "AK","AL","AM",..: 2 2 2 2 2 2 2 2 2 2 ...
##  $ EVTYPE    : Factor w/ 985 levels "   HIGH SURF ADVISORY",..: 826 826 826 826 826 826 826 826 826 826 ...
##  $ BGN_RANGE : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ BGN_AZI   : Factor w/ 35 levels "","  N"," NW",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ BGN_LOCATI: Factor w/ 54429 levels ""," Christiansburg",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ END_DATE  : Factor w/ 6663 levels "","1/1/1993 0:00:00",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ END_TIME  : Factor w/ 3647 levels ""," 0900CST",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ 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   : Factor w/ 24 levels "","E","ENE","ESE",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ END_LOCATI: Factor w/ 34506 levels ""," CANTON"," TULIA",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ 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: Factor w/ 19 levels "","+","-","0",..: 16 16 16 16 16 16 16 16 16 16 ...
##  $ CROPDMG   : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ CROPDMGEXP: Factor w/ 9 levels "","0","2","?",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ WFO       : Factor w/ 542 levels ""," CI","$AC",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ STATEOFFIC: Factor w/ 250 levels "","ALABAMA, Central",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ ZONENAMES : Factor w/ 25112 levels "","                                                                                                                               "| __truncated__,..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ 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   : Factor w/ 436781 levels "","\t","\t\t",..: 1 1 1 1 1 1 1 1 1 1 ...
##  $ REFNUM    : num  1 2 3 4 5 6 7 8 9 10 ...

As you can see, the file have 902297 observations and 37 variables (columns)

head(storm)
##   STATE__           BGN_DATE BGN_TIME TIME_ZONE COUNTY COUNTYNAME STATE
## 1       1  4/18/1950 0:00:00     0130       CST     97     MOBILE    AL
## 2       1  4/18/1950 0:00:00     0145       CST      3    BALDWIN    AL
## 3       1  2/20/1951 0:00:00     1600       CST     57    FAYETTE    AL
## 4       1   6/8/1951 0:00:00     0900       CST     89    MADISON    AL
## 5       1 11/15/1951 0:00:00     1500       CST     43    CULLMAN    AL
## 6       1 11/15/1951 0:00:00     2000       CST     77 LAUDERDALE    AL
##    EVTYPE BGN_RANGE BGN_AZI BGN_LOCATI END_DATE END_TIME COUNTY_END
## 1 TORNADO         0                                               0
## 2 TORNADO         0                                               0
## 3 TORNADO         0                                               0
## 4 TORNADO         0                                               0
## 5 TORNADO         0                                               0
## 6 TORNADO         0                                               0
##   COUNTYENDN END_RANGE END_AZI END_LOCATI LENGTH WIDTH F MAG FATALITIES
## 1         NA         0                      14.0   100 3   0          0
## 2         NA         0                       2.0   150 2   0          0
## 3         NA         0                       0.1   123 2   0          0
## 4         NA         0                       0.0   100 2   0          0
## 5         NA         0                       0.0   150 2   0          0
## 6         NA         0                       1.5   177 2   0          0
##   INJURIES PROPDMG PROPDMGEXP CROPDMG CROPDMGEXP WFO STATEOFFIC ZONENAMES
## 1       15    25.0          K       0                                    
## 2        0     2.5          K       0                                    
## 3        2    25.0          K       0                                    
## 4        2     2.5          K       0                                    
## 5        2     2.5          K       0                                    
## 6        6     2.5          K       0                                    
##   LATITUDE LONGITUDE LATITUDE_E LONGITUDE_ REMARKS REFNUM
## 1     3040      8812       3051       8806              1
## 2     3042      8755          0          0              2
## 3     3340      8742          0          0              3
## 4     3458      8626          0          0              4
## 5     3412      8642          0          0              5
## 6     3450      8748          0          0              6

We can realize that there are hardly any measurements in the early years.Perhaps we can see better if we plot the file

Format the Date column

storm$BGN_DATE <- as.Date(storm$BGN_DATE, "%m/%d/%Y %H:%M:%S")
hist(storm$BGN_DATE, breaks = 20)

storm2 <- storm[storm$FATALITIES != 0 | storm$INJURIES != 0 , c("EVTYPE", "FATALITIES","INJURIES") ]
aggrf <- aggregate(FATALITIES ~ EVTYPE, storm2, sum)
indexf <- order(aggrf$FATALITIES, decreasing = TRUE)
ord_aggrf <- aggrf[indexf, ]
colnames(ord_aggrf) <- c("Events", "Fatalities")
aggri <- aggregate(INJURIES ~ EVTYPE, storm2, sum)
indexi <- order(aggri$INJURIES, decreasing = TRUE)
ord_aggri <- aggri[indexi, ]
colnames(ord_aggri) <- c("Events", "Injuries")

Economy Damage

storm_ECO <- storm[storm$PROPDMG != 0 | storm$CROPDMG != 0 , c("EVTYPE", "PROPDMG","CROPDMG") ]
aggrpr <- aggregate( PROPDMG ~ EVTYPE, storm_ECO, sum)
index_pr <- order(aggrpr$PROPDMG, decreasing = TRUE)
ord_aggrpr <- aggrpr[index_pr, ]
colnames(ord_aggrpr) <- c("Events", "PropertiesDM")
aggrcr <- aggregate( CROPDMG~ EVTYPE, storm_ECO, sum)
index_cr <- order(aggrcr$CROPDMG, decreasing = TRUE)
ord_aggrcr <- aggrcr[index_cr, ]
colnames(ord_aggrcr) <- c("Events", "CropsDM")

Results

Population Health

These are the Fatalities by Weather Event

head(ord_aggrf)
##             Events Fatalities
## 183        TORNADO       5633
## 31  EXCESSIVE HEAT       1903
## 41     FLASH FLOOD        978
## 68            HEAT        937
## 122      LIGHTNING        816
## 189      TSTM WIND        504

These are the Injuries by Weather Event

head(ord_aggri)
##             Events Injuries
## 183        TORNADO    91346
## 189      TSTM WIND     6957
## 46           FLOOD     6789
## 31  EXCESSIVE HEAT     6525
## 122      LIGHTNING     5230
## 68            HEAT     2100

we would like to respect the order in data.frame. For that to happen, we need to change the order of factor levels by specifying the order explicitly.

ord_aggrf20 <- ord_aggrf[1:15,]
 ord_aggrf20$Events <- factor(ord_aggrf20$Events, levels = ord_aggrf20$Events[order(ord_aggrf20$Fatalities)])
ord_aggri20 <- ord_aggri[1:15,]
 ord_aggri20$Events <- factor(ord_aggri20$Events, levels = ord_aggri20$Events[order(ord_aggri20$Injuries)])

These are the result plot that show which types of events are most harmful with respect to population health.

Economy Damage

These are the Properties Damage by Weather Event

head(ord_aggrpr)
##                Events PropertiesDM
## 351           TORNADO    3212258.2
## 58        FLASH FLOOD    1420124.6
## 365         TSTM WIND    1335965.6
## 71              FLOOD     899938.5
## 311 THUNDERSTORM WIND     876844.2
## 114              HAIL     688693.4

These are the Crops Damage by Weather Event

head(ord_aggrpr)
##                Events PropertiesDM
## 351           TORNADO    3212258.2
## 58        FLASH FLOOD    1420124.6
## 365         TSTM WIND    1335965.6
## 71              FLOOD     899938.5
## 311 THUNDERSTORM WIND     876844.2
## 114              HAIL     688693.4

we would like to respect the order in data.frame to plot it. For that to happen, we need to change the order of factor levels by specifying the order explicitly.

ord_aggrpr20 <- ord_aggrpr[1:15,]
 ord_aggrpr20$Events <- factor(ord_aggrpr20$Events, levels = ord_aggrpr20$Events[order(ord_aggrpr20$PropertiesDM)])
ord_aggrcr20 <- ord_aggrcr[1:15,]
 ord_aggrcr20$Events <- factor(ord_aggrcr20$Events, levels = ord_aggrcr20$Events[order(ord_aggrcr20$CropsDM)])

These are the result plot that show which types of events have the greatest economic consequences.