1 of 2

Climate Toolbox Activities

FUTURE FIRE DANGER

In this activity, we will explore future fire danger in the forests near Portland, Oregon by utilizing the Future Boxplots Tool in the Climate Toolbox.

Climate Effects

​

As seen at the entrance to many national and state parks, the Smokey Bear fire danger sign places daily fire danger into one of 5 categories: low, moderate, high, very-high and extreme. These categories correspond to current vegetation dryness (using 100-hr fuel moisture) within certain percentile ranks:

  • Low: 50 - 100 percentile
  • Medium: 20-50 percentile
  • High: 10-20 percentile
  • Very-High: 3-10 percentile
  • Extreme: 0-3 percentile

i.e. when dryness of a day is ranked at the 0th percentile from all days of the year in 1950-2005, that’s the driest conditions in that period.

EXPLORE FUTURE FIRE DANGER

NEAR PORTLAND, OREGON

ClimateToolbox.org

Smokey Bear Fire Danger Classification

Fire danger is greatest on days when there is low humidity (<15%) and very dry fuels (grass, shrubs, trees, houses, etc). Under these conditions, a lightning strike or human-caused ignition could be enough to start a fire. Other weather conditions, such as high winds and hot temperatures, could exacerbate any fire that starts into a bigger fire.

The 100-hour fuel moisture is a measure of the amount of moisture in dead vegetation in the 1-3” diameter class available to burn in a fire, expressed as a percent of the dry weight of the fuel. Low fuel moisture percentage indicates dry conditions, while high fuel moisture percentage indicates wet conditions.

Fire Danger

Vegetation Dryness

Fire Danger Ratings

2 of 2

ClimateToolbox.org

Data

 

FUTURE FORESTS

The future fire danger data used in this activity was produced by using the National Fire Danger Rating System (NFDRS) model G (for conifer forests) to generate daily estimates of the 100-hour fuel moisture. The NFDRS model utilizes daily future climate projections of temperature, precipitation, humidity, wind speed and solar radiation from 10 different global climate models and 2 future greenhouse gas emission scenarios (RCP 4.5, 8.5) from CMIP5. The fuel moisture values are assigned a percentile rank based on ordering all fuel moistures observed from any day of the year from 1950-2005. The percentile ranks are then assigned a fire danger category of low, median, high, very-high or extreme. The final metric is the number of days from each year that were observed in each fire danger category (low, medium, high, very-high and extreme fire danger).

Activity

Create a climate data story on future fire danger for forested areas near Portland.

Prepare a 3-5 min presentation (2 slides) on your story.

The Facts (Slide 1)

The Meaning (Slide 2)

  • Go to the Future Boxplots Tool (ClimateToolbox.org)
  • Select location: Portland, OR
  • Select variable: "Extreme" Fire Danger Days
  • Select future scenario: RCP 8.5
  • Hover over the value for 1971-2000 and record the value.
  • Look at the boxplot. What do the dots represent? What does the horizontal line represent? What information does the spread of the dots give you?
  • Hover over the boxplot for 2010-2039 and 2040-2069 and record the median value. Estimate an uncertainty (plus/minus) with the range from the 5th to 95th percentiles.
  • Is there a trend in the median with time?
  • Is this trend within the uncertainty? i.e. is the 2040-2069 median outside the uncertainty window for 2010-2039?
  • How many models agree on an increase with time?

To Do

  • Search the internet for a picture of Smokey Bear and the fire danger rating sign.
  • Create a table on your slide to show the data for the case of Extreme Fire Danger for 3 time periods and 2 scenarios. Fill the table with data (medians & +/- uncertainty)

Prepare Slide

  • 2 boxplots -Extreme Fire Danger days for RCP 4.5 and 8.5.
  • Add title, labels, units
  • Add text for medians and +/- uncertainty

To Do

Prepare Slide

  • Picture of Smokey Bear and fire rating sign
  • Table of data for Extreme Fire Danger Days
  • Add title, units, source.

Prepare Talking Points

  • What are the projections for the trend in days of extreme fire days?
  • Is there a generatlization that can be made about fire danger in a warming climate?
  • How many models agree on this?
  • The future is not set in stone. If we reduce emissions (esp. coal), our future could be the RCP 4.5 scenario not the RCP 8.5.