Contemporary Pyrogeography and Wildfire-Climate Relationships of South Dakota, USA

Darren Clabo

doi:10.3390/atmos9060207

Abstract

A recent wildland fire history and climate database was compiled for South Dakota, USA (SD). Wildfires are generally a warm season phenomenon across central and western SD while eastern SD exhibits a spring peak in annual wildfire activity. It is hypothesized that regional climate and land use are the two primary drivers of the spatiotemporal wildfire distribution across the state. To assess the relative impacts of climate to wildfire activity, Spearman’s rank order correlation coefficients were calculated for monthly values of temperature, precipitation, and the Palmer Drought Modified Index (PMDI) as compared to both monthly area burned and numbers of fire starts data for each of the nine climate divisions in South Dakota. Results show statewide variations in significant correlations but positive temperature anomalies, negative precipitation anomalies, and negative values of the PMDI were most frequently associated with months showing substantial area burned and large numbers of wildfire starts. Time-lagged significant correlations were also seen implying month(s)-ahead predictive capabilities. Positive PMDI values were most significantly correlated to warm season wildfire activity suggesting that the influence of drought on wildfires within SD may be limited to the summer months.

Highlights

Knowledge of wildfire-climate relationships is vital in understanding the favorable environmental conditions for large wildfire growth
The purpose of this study is to examine the contemporary wildfire climatology and pyrogeography of South Dakota and to establish linkages between wildfire and climate metrics such as temperature, precipitation, and drought
Wildfires are most common during the warm season throughout central and western SD with moderate wildfire activity extending into the fall months

Summary

Introduction

Knowledge of wildfire-climate relationships is vital in understanding the favorable environmental conditions for large wildfire growth. Climate is a primary control on local weather [1] and vegetation/fuel conditions [2,3] thereby largely dictating wildfire seasonality, location, and severity [4]. Anthropogenic factors (i.e., land use, ignitions) impact regional wildfire climatology [5,6]. Wildfires are not distributed globally [7,8] with the most frequent wildfires occurring in regions where fuel availability meets favorable climatic conditions. The specific spatial and temporal characteristics of wildfire differ substantially from region to region around the world [9,10,11,12]. The wildfire climatology of the conterminous United

Objectives

Methods

Results

Discussion

Conclusion