Soil Moisture and Wildfire - Improving Fire Danger Rating Systems: November 16, 2022

Welcome and Introduction

Speaker: Marina Skumanich, NOAA's National Integrated Drought Information System (NIDIS), National Coordinated Soil Moisture Monitoring Network

• Introduction to the seminar series. Today's topic is soil moisture and wildfire, specifically the opportunities to improve fire danger rating systems.
• Overview of the National Coordinated Soil Moisture Monitoring Network (NCSMMN): Coordinated, high-quality nationwide soil moisture information for the public good.

Using Soil Moisture Information to Better Understand and Predict Wildfire Danger

Speaker: Tyson Ochsner, Oklahoma State University

This presentation included an overview of soil moisture and wildfire research, with a focus on opportunities to apply soil moisture information to improve fire danger rating systems and fire management. 

• Read the abstract of the researchers' article in the International Journal of Wildland Fire.
• Our motivating question: How can increasingly available soil moisture information be used to better manage the impacts of fire on people and ecosystems?
• A decade-long journey of discovery:
  • Soil moisture affects growing-season wildfire size in the southern Great Plains (Krueger et al., 2015).
  • Concurrent and antecedent soil moisture related differently to wildfire in different seasons (Krueger et al., 2016).
  • Soil moisture is a better growing-season wildfire predictor than the Keetch-Byram Drought Index (KBDI), a widely used drought index (Krueger et al., 2017).
  • Grassland fuel moisture and curing are strongly linked to soil moisture (Sharma et al., 2020).
  • Soil moisture information can help improve predictions of grassland fuel loads (Krueger et al., 2021).
• The current situation: A growing body of research provides strong evidence that soil moisture is a key predictor of wildfire danger that has not yet been effectively integrated into fire danger rating.
• Some key remaining questions:
  • How can we best represent soil moisture (absolute values, fraction of available water [FAW], anomalies, percentiles, etc.)? 
  • What are the most relevant soil depths to consider? 
  • How can in situ, remotely sensed, and modeled soil moisture data best be utilized? 
  • How can soil moisture conditions predict burning of organic soils? 
  • How do soil moisture conditions influence prescribed fires? 
  • How can wildfire professionals be convinced and enabled to use soil moisture information?

High-Resolution Daily Gridded Soil Moisture Modeling for the Conterminous U.S.

Speaker: Zach Holden, U.S. Forest Service Region 1

This presentation focused on Topofire, a high-resolution (250-meter) modeling system being used to develop a revised version of the Keetch-Byram Drought Index (KBDI; used by the U.S. Forest Service to determine forest fire potential in the coterminous U.S.) that accounts for snow melt, soil moisture, and evapotranspiration. 

• Current soil moisture data:
  • Current soil moisture maps
  • Daily historical grids
• Next steps:
  • Updated Keetch-Byram Drought Index (KBDI)
  • Analysis of historical wildfire activity and soil moisture relationships

General Discussion

End of Seminar

Read the abstract for a soon-to-be available review article on this topic by the seminar presenters and others: 

Krueger et. al. 2022. Using Soil Moisture Information to Better Understand and Predict Wildfire Danger: A Review of Recent Developments and Outstanding Questions, International Journal of Wildland Fire.