Randi Jandt

University of Alaska Fairbanks · International Arctic Research Center

Studies in recent decades show strong evidence of physical and biological changes in the Arctic tundra largely in response to exceptionally rapid rates of warming. Given the important implications of these changes on ecosystem services, hydrology, surface energy balance, carbon budgets, and climate feedbacks, research on the trends and patterns of...

Few fires are known to have burned the tundra of the Arctic Slope north of the Brooks Range in Alaska, USA. A total of 90 fires between 1969 and 2022 are known. Because fire has been rare, old burns can be detected by the traces of thermokarst and distinct vegetation they leave in otherwise uniform tundra, which are visible in aerial photograph arc...

Detailed vegetation maps are one of the primary inputs for forest and wildfire management. Hyperspectral remote sensing is a proven technique for detailed and accurate vegetation mapping. However, the availability of recent hyperspectral imagery in Alaska is limited because of the logistics and high cost involved in its acquisition. In this study,...

Circumpolar tundra has experienced a greater increase in temperatures compared to any other biome, with a magnitude of the increase nearly three times the global average. Widespread shrubification associated with pronounced observed warming is gradually transforming the tundra ecosystem structure and function. This study confirms that a shrub-domin...

We used full polarimetric L-band and P-band synthetic aperture radar (SAR) data collected from the recent NASA Arctic Boreal Vulnerability Experiment (ABoVE) airborne campaign and Sentinel-1 C-band dual-polarization data to understand the sensitivity of radar backscatter intensity and phase to fire-induced changes in the surface and subsurface soil...

Wildfire has become a larger threat to human life and property with the proliferation of homes into the wildland urban interface and warming climate. In this study we explored Alaskan homeowner preferences for wildfire risk mitigation in the wildland urban interface using discrete choice experiments to better understand the drivers of their risk mi...

Documented substantial changes to plant composition, topography, and soil temperature post-fire over 10 years at the Anaktuvuk River fire in arctic Alaska.

Forest fires are usually viewed within the context of a single fire season, in which weather conditions and fuel supply can combine to create conditions favourable for fire ignition—usually by lightning or human activity—and spread1–3. But some fires exhibit ‘overwintering’ behaviour, in which they smoulder through the non-fire season and flare up...

Alaska has witnessed a significant increase in wildfire events in recent decades that have been linked to drier and warmer summers. Forest fuel maps play a vital role in wildfire management and risk assessment. Freely available multispectral datasets are widely used for land use and land cover mapping, but they have limited utility for fuel mapping...

The late-season extreme fire activity in Southcentral Alaska during 2019 was highly unusual and consequential. Firefighting operations had to be extended by a month in 2019 due to the extreme conditions of hot summer temperature and prolonged drought. The ongoing fires created poor air quality in the region containing most of Alaska’s population, l...

Lightning is a key driver of wildfire activity in Alaska. Quantifying its historical variability and trends has been challenging because of changes in the observational network, but understanding historical and possible future changes in lightning activity is important for fire management planning. Dynamically downscaled reanalysis and global clima...

Observations taken over the last few decades indicate that dramatic changes are occurring in the Arctic‐Boreal Zone (ABZ), which are having significant impacts on ABZ inhabitants, infrastructure, flora and fauna, and economies. While suitable for detecting overall change, the current capability is inadequate for systematic monitoring and for improv...

Final research report to the Joint Fire Science Program: Wildland fire is the dominant disturbance agent of the boreal forest of Alaska. Currently, about 80% of the population of Alaska resides in communities potentially at risk from wildland fire. The wildland fire threat to these settlements is increasing because of increased suburban constructio...

This compilation is intended to provide an illustrated overview of the current science of fuelbreaks in Alaska boreal forest, with citations and links to additional reference material for practitioners and the public. Research on fuelbreaks in the high northern latitudes is scarce, yet there is a pressing need for strategies to improve infrastructu...

Changes in climate and fire regimes are transforming the boreal forest, the world’s largest biome. Boreal North America recently experienced two years with large burned area: 2014 in the Northwest Territories and 2015 in Alaska. Here we use climate, lightning, fire and vegetation data sets to assess the mechanisms contributing to large fire years....

As the permafrost region warms, its large organic carbon pool will be increasingly vulnerable to decomposition, combustion, and hydrologic export. Models predict that some portion of this release will be offset by increased production of Arctic and boreal biomass; however, the lack of robust estimates of net carbon balance increases the risk of fur...

A multidecadal analysis of fire in Alaskan Arctic tundra was completed using records from the Alaska Large Fire Database. Tundra vegetation fires are defined by the Circumpolar Arctic Vegetation Map and divided into five tundra ecoregions of Alaska. A detailed review of fire records in these regions is presented, and an analysis of future fire pote...

Mechanical (e.g., shearblading) and manual (e.g., thinning) fuel treatments have become the preferred strategy of many fire managers and agencies for reducing fire hazard in boreal forests. This study attempts to characterize the effectiveness of four fuel treatments through direct measurement of fire intensity and forest floor consumption during a...

The 2007 Anaktuvuk River Fire was an order of magnitude larger than the average fire size in the historic record for northern Alaska and indices of severity were substantially higher than for other recorded tundra burns. An interdisciplinary team assessed fire effects including burn severity, potential plant community shifts, and effects on permafr...

Arctic tundra soils store large amounts of carbon (C) in organic soil layers hundreds to thousands of years old that insulate, and in some cases maintain, permafrost soils. Fire has been largely absent from most of this biome since the early Holocene epoch, but its frequency and extent are increasing, probably in response to climate warming. The ef...

Large fires are uncommon in Alaskan arctic tundra. However, the frequency of lightning strikes on the North Slope of Alaska has increased greatly in the past two decades as climate has warmed. The Anaktuvuk River Fire (ARF) of 2007 burned 1000 km2 on the Alaskan North Slope, and was unprecedented in terms of area burned and severity for tundra fire...

A synthesis was carried out to examine Alaska's boreal forest fire regime. During the 2000s, an average of 767 000 ha.year(-1) burned, 50% higher than in any previous decade since the 1940s. Over the past 60 years, there was a decrease in the number of lightning-ignited fires, an increase in extreme lightning-ignited fire events, an increase in hum...

The population of the Western Arctic Herd, estimated at 490 000 caribou (Rangifer tarandus granti) in 2003, is at its highest level in 30 years. Twenty permanent range transects were established in the winter range of the Western Arctic Herd in 1981 to assess the impacts of grazing. These transects were revisited in 1995 and 1996 (1995/96). Only 18...

We review and present a synthesis of the existing research dealing with changing Arctic tundra ecosystems, in relation to caribou and reindeer winter ranges. Whereas pan-Arctic studies have documented the effects on tundra vegetation from simulated climate change, we draw upon recent long-term regional studies in Alaska that have documented the act...

A predicted consequence of human-caused climate warming at high latitudes is an increase in the frequency, intensity and aerial extent of wildfires. This could feedback positively to climate warming by transferring carbon (C) stored in terrestrial ecosystems to the atmosphere and altering ecosystem structure and function. Between July 16 and Octobe...

We review and present a synthesis of the existing research dealing with changing Arctic tundra ecosystems, in relation to caribou and reindeer winter ranges. Whereas pan-Arctic studies have documented the effects on tundra vegetation from simulated climate change, we draw upon recent long-term regional studies in Alaska that have documented the act...

Background/Question/Methods: A predicted consequence of human-caused climate warming at high latitudes is an increase in the frequency, intensity and aerial extent of wildfires. This could feedback positively to climate warming by transferring carbon (C) stored in terrestrial ecosystems to the atmosphere and altering ecosystem structure and functio...

In 2007, the Anaktuvuk River Fire (ARF) became the largest recorded tundra fire Oil the North Slope of Alaska. The ARF burned for nearly three months. consuming more than 100,000 ha. At its peak in early September, the ARF burned at a rate of 7000 ha d(-1). The conditions potentially responsible for this large tundra fire include modeled record hig...

Wildfire is the dominant ecological driver in boreal forest ecosystems. Although much less is known, it also affects tundra ecosystems. Fires effectively consume fruticose lichens, the primary winter forage for caribou, in both boreal and tundra ecosystems. We summarize 1950-2007 fire regime data for northwestern Alaska and sub-regions. We also ide...

Lichen regeneration timelines are needed to establish sound fire management guidelines for caribou (Rangifer tarandus) winter range. Paired burned and unburned permanent vegetative cover transects were established after 1981, 1977, and 1972 tundra fires in northwestern Alaska to document regrowth of tundra vegetation including caribou forage lichen...

We compared winter diets of Western Arctic Herd Caribou (Rangifer tarandus) from 1995/1996 and 2005 using microhistological fecal analysis on samples collected at paired permanent vegetation transects. Changes in the diets of Caribou followed the same trends as vegetative changes documented in long-term studies in northwestern Alaska. Lichens were...

This report summarizes activities from 2002 to 2004 undertaken by the U.S. Bureau of Land Management’s Alaska Fire Service and cooperating agencies to better understand the influence of forest floor moisture content on fire behavior in interior Alaska boreal spruce forest. Forest floor moisture measurements were derived by removing individual layer...

A 1977 tundra fire burned a hillslope where prefire soils and vegetation ranged from poorly drained moist tussock-shrub tundra on the lower slopes to well-drained dwarf shrub tundra on the back slope and very poorly drained wet sedge meadow on the flat crest. We sampled the vegetation on this slope before the fire and at 8 sites following the fire...