Introduction

Colorado, as a state, has proven susceptible to wildfires in its past. More recently, however, Colorado continues to remain affected by the danger of wildfires and the damages they cause.
In 2019, Colorado ranked third within the western states for highest wildfire risk. This ranking was based off of the number of properties in the state at risk.
Source: https://www.iii.org/fact-statistic/facts-statistics-wildfires

Now, in 2020, the state continues to face the danger of this natural disaster. According to NBC News, “3 of the largest wildfires in Colorado history have occurred in 2020.” Source: https://www.nbcnews.com/news/us-news/3-largest-wildfires-colorado-history-have-occurred-2020-n1244525

Boulder County, specifically, is a county of interest because Colorado’s flagship university is located in Boulder. Furthermore, Boulder County is particularly intriguing because it is one of the few counties that is highly populated and is home to a city, but also in a location where there is a large amount of open space and land. Thus, the risk of wildfires is present.

This project aims to analyze the history of wildfires in Boulder County, Colorado and its relationship with temperature, precipitation, and snowfall.

Hypothesis

I predict that there is a correlation between the number of wildfires per year in Boulder and the temperature, rainfall, and snowfall. During the years when more wildfires took place, I would expect that Boulder experienced higher temperatures, less rainfall, and less snowfall in comparison to other years.

Setup

In order to run certain functions, I first had to run the necessary packages.

library(tidyverse)
library(rvest)
library(ggplot2)

Tableau Map

After downloading the required packages, I then uploaded a map I created in Tableau. The Tableau map illustrates, in a visual way, the location and year of all wildfires in Boulder County. The first wildfire located on the map was in 1974, and the most recent wildfire on the map took place in 2017. The most fires in one year within the county took place in 2000. In 2000, there were 9 fires. The second highest year for wildfires was 2011, when 5 wildfires occurred. Between the span of 2009 and 2012, 12 fires took place within the county. The data source for the Tableau map was Boulder County Open Data. I downloaded the data as a GeoJSON and imported it into Tableau. Source: https://opendata-bouldercounty.hub.arcgis.com/datasets/wildfire-history

History of Wildfires in Boulder County

Fire History in Boulder

  1. 1974–1 fire
  2. 1976–1 fire
  3. 1978–1 fire
  4. 1988–2 fires
  5. 1989–1 fire
  6. 2000–9 fires
  7. 2002–1 fire
  8. 2003–3 fires
  9. 2004–1 fire
  10. 2005–1 fire
  11. 2006–2 fires
  12. 2008–1 fire
  13. 2009–2 fires
  14. 2010–3 fires
  15. 2011–5 fires
  16. 2012–2 fires
  17. 2016–1 fire
  18. 2017–4 fires

Average Temperature in Boulder (Fahrenheit)

  1. 1974–51.3
  2. 1976–51.1
  3. 1978–50.2 LOWEST
  4. 1988–x
  5. 1989–x
  6. 2000–51.9
  7. 2002–51.8
  8. 2003–53.4 2nd HIGHEST
  9. 2004–51.3
  10. 2005–52.4
  11. 2006–52.9
  12. 2008–50.7 2nd LOWEST 13.2009–50.8
  13. 2010–50.8
  14. 2011–51.7
  15. 2012–54.6 HIGHEST
  16. 2016–53.3
  17. 2017–53.3

AVERAGE TEMPERATURE PER YEAR: 51.9 Fahrenheit

According to the National Oceanic and Atmospheric Administration, the two years, between 1974 and 2017, that had the highest average temperatures were 2012 and 2003, respectively. In 2012, Boulder’s average temperature was 54.6, and in 2003 Boulder’s average temperature was 53.4.

Looking back at the wildfire data, there was 2 fires in 2012 and 3 fires in 2003.

On the other hand, the two years, between 1974 and 2017, that had the lowest average temperatures were 1978 and 2008, respectively. In 1978, Boulder’s average temperature was 50.2, and in 2008 Boulder’s average temperature was 50.7.

Looking back at the wildfire data, there was 1 fire in 1978 and 1 fire in 2008.

MAYBE CORRELATION…Higher temperatures could be a cause for more fires, and vice versa.

In 2000, Boulder experienced the most fires, with 9. That year, the average temperature was 51.9. The average temperature between 1974 and 2017 per year was 51.9.

Source: https://psl.noaa.gov/boulder/Boulder.mm.html

temps <- read_csv("~/Desktop/temps.csv", 
  col_types = cols(Year = col_date(format = "%Y"), 
  Average = col_number()))


snow <- read_csv("~/Desktop/snow.csv", 
    col_types = cols(Year = col_date(format = "%Y"), 
        Jan = col_number(), Feb = col_number(), 
        Mar = col_number(), Apr = col_number(), 
        May = col_number(), Jun = col_number(), 
        Jul = col_number(), Aug = col_number(), 
        Sep = col_number(), Oct = col_number(), 
        Nov = col_number(), Dec = col_number(), 
        `Total Sep-Jun` = col_number(), `Total Jan-Dec` = col_number()))
temps %>%  
  filter(Year > 1973) %>%  
ggplot(aes(Year, Average)) + geom_bar(stat="identity")
## Warning: Removed 5 rows containing missing values (position_stack).

temps %>%  
  filter(Year > 1973) %>% 
  ggplot(aes(Year, Average)) + geom_point() +   
  geom_smooth(aes(Year, Average))
## `geom_smooth()` using method = 'loess' and formula 'y ~ x'
## Warning: Removed 5 rows containing non-finite values (stat_smooth).
## Warning: Removed 5 rows containing missing values (geom_point).

Precipitation in Boulder (inches)

  1. 1974–15.11
  2. 1976–14.66 2nd LOWEST
  3. 1978–23.82 2nd HIGHEST
  4. 1988–16.95
  5. 1989–20.62
  6. 2000–15.96
  7. 2002–13.88 LOWEST
  8. 2003–22.02
  9. 2004–27.17 HIGHEST
  10. 2005–17.52
  11. 2006–19.31
  12. 2008–17.02
  13. 2009–22.19
  14. 2010–20.32
  15. 2011–22.29
  16. 2012–15.65
  17. 2016–17.25
  18. 2017–21.89

AVERAGE AMOUNT OF PRECIPITATION PER YEAR: 19.09 inches

According to the National Oceanic and Atmospheric Administration, the two years, between 1974 and 2017, that received the most precipitation were 2004 and 1978, respectively. In 2004, Boulder received 27.17 inches of precipitation, and in 1978 Boulder received 23.82 inches of precipitation.

Looking back at the wildfire data, there was 1 fire in 2004 and 1 fire in 1978.

On the other hand, the two years, between 1974 and 2017, that received the least amount of precipitation were 2002 and 1976, respectively. In 2002, Boulder received 13.88 inches of precipitation, and in 1976 Boulder received 14.66 inches of precipitation.

Looking back at the wildfire data, there was 1 fire in 2002 and 1 fire in 1976.

Source: https://psl.noaa.gov/boulder/Boulder.mm.precip.html

In 2000, Boulder experienced the most fires, with 9. That year, there were 15.96 inches of precipitation. The average amount of precipitation between 1974 and 2017 per year was 19.09 inches, thus 2000’s 15.96 inches is below average precipitation for a year, but not one of the lowest.

NO CORRELATION…There is not a clear correlation between less precipitation and more fires, and more precipitation and less fires.

Snowfall in Boulder County Per Year (inches)

  1. 1974–83.8
  2. 1976–58.9
  3. 1978–76.0
  4. 1988–94.8
  5. 1989–92.5
  6. 2000–72.6
  7. 2002–63.4
  8. 2003–99.0
  9. 2004–70.6
  10. 2005–76.7
  11. 2006–51.4 2nd LOWEST
  12. 2008–82.9
  13. 2009–81.1
  14. 2010–135.4 HIGHEST
  15. 2011–47.3 LOWEST
  16. 2012–94.7
  17. 2016–109.7 2nd HIGHEST
  18. 2017–71.5

AVERAGE AMOUNT OF SNOW PER YEAR: 81.23 inches

According to the National Oceanic and Atmospheric Administration, the two years, between 1974 and 2017, that received the most snowfall were 2010 and 2016, respectively. In 2010, Boulder received 135.4 inches of snow, and in 2016 Boulder received 109.7 inches of snow.

Looking back at the wildfire data, there were 3 fires in 2010 and 1 fire in 2016.

NO CORRELATION…More snow does not equal less fires.

On the other hand, the two years, between 1974 and 2017, that received the least amount of snowfall were 2011 and 2006, respectively. In 2011, Boulder received 47.3 inches of snowfall, and in 2006 Boulder received 51.4 inches of snowfall.

Looking back at the wildfire data, there were 5 fires in 2011 and 2 fires in 2006.

MAYBE CORRELATION…Less snow could lead to more fires, but not directly.

2000 could have been a strange circumstance. 2000 experienced the most fires, with 9 total. However, that year was not the lowest amount of snowfall. That year there was 72.6 inches of snowfall, which is not the lowest, or second lowest, between 1974 and 2017. The average amount of snowfall between 1974 and 2017 per year was 81.23 inches, thus 2000’s 72.6 inches is below average snowfall for a year, but not one of the lowest.

Source: https://psl.noaa.gov/boulder/bouldersnow.html

snow %>%  
  filter(Year > 1973) %>% 
  arrange(desc(`Total Sep-Jun`)) %>%
  ggplot(aes(Year, `Total Sep-Jun`)) + geom_bar(stat="identity") + theme(axis.text.x = element_text(angle = 60, hjust=1))

snow %>%
  filter(Year > 1973) %>%   
  arrange(desc(`Total Sep-Jun`)) %>%  
  ggplot(aes(Year, `Total Sep-Jun`)) + geom_point() + 
  geom_smooth() +
  theme(axis.text.x = element_text(angle = 60, hjust=1))
## `geom_smooth()` using method = 'loess' and formula 'y ~ x'

Conclusion

In regard to temperature, it is evident that the average temperature in Boulder County has increased over time. This is clear. Yet, the number of wildfires over time in Boulder County has not been explicitly linear, in the sense that there has not been a steady increase of wildfires over time. With this in mind, it does not appear that the increasing temperature in the county has a direct effect on the number of fires.

The relationship between precipitation and wildfires is also not evident. The years where there were higher levels of precipitation, the number of wildfires was still above average. A specifically intriguing year was 2000. In 2000, Boulder experienced the most fires, with 9. That year, there were 15.96 inches of precipitation. The average amount of precipitation between 1974 and 2017 per year was 19.09 inches, thus 2000’s 15.96 inches is below average precipitation for a year, but not one of the lowest.

The relationship between snowfall and wildfires in Boulder County is slightly more evident, but not clear cut. Similar to temperature, the average snowfall in Boulder has increased over time, but barely. In the years where Boulder received the least amount of snow, comparatively, there were more wildfires those years. Yet, the years where Boulder received the highest amounts of snow, there were still an above average number of wildfires that took place.