Research Database
Displaying 21 - 25 of 25
Did the 2002 Hayman Fire, Colorado, USA, Burn with Uncharacteristic Severity?
Year: 2016
There is considerable interest in evaluating whether recent wildfires in dry conifer forests of western North America are burning with uncharacteristic severity—that is, with a severity outside the historical range of variability. In 2002, the Hayman Fire burned an unlogged 3400 ha dry conifer forest landscape in the Colorado Front Range, USA, that had been the subject of previous fire history and forest age structure research. We opportunistically leveraged pre-existing data from this research, in combination with post-fire aerial imagery, to provide insight into whether the Hayman Fire’s…
Publication Type: Journal Article
A state-and-transition simulation modeling approach for estimating the historical range of variability
Year: 2015
Reference ecological conditions offer important context for land managers as they assess the condition of their landscapes and provide benchmarks for desired future conditions. State-and-transition simulation models (STSMs) are commonly used to estimate reference conditions that can be used to evaluate current ecosystem conditions and to guide land management decisions and activities. The LANDFIRE program created more than 1,000 STSMs and used them to assess departure from a mean reference value for ecosystems in the United States. While the mean provides a useful benchmark, land managers and…
Publication Type: Journal Article
Increasing weight of evidence that thinning and burning treatments help restore understory plant communities in ponderosa pine forests
Year: 2015
For more than a century ecosystems around the world have experienced an increase in the dominance of woody species. While the drivers of woody plant proliferation are complex, interactions between climate and land-use change are commonly invoked as primary contributing factors. In ponderosa pine forests of western North America, substantial increases in tree densities are impacting overall forest health and increasing the risk for severe wildfires and insect and disease outbreaks. Addressing this problem through the use of ecological restoration projects is widely advocated. Our objective was…
Publication Type: Journal Article
Historic Variability: Informing Restoration Strategies, Not Prescribing Targets
Year: 2014
The concept of historic range of variability (HRV) is briefly evaluatedwithin the context of its application in ecosystem managementover the past two decades. Despite caveats to the contrary, animplicit assumption continues to emerge of climatic stationarity,and, by corollary, that presettlement centuries provide an appropriatereference period. This is examined from the perspective ofhistoric climate change and ecosystem response. As a means ofdeveloping reference prescriptions and management targets, HRVis generally inappropriate, although if historic periods are usedfor reconstruction that…
Publication Type: Journal Article
Communication of the Role of Natural Variability in Future North American Climate
Year: 2012
As climate models improve, decision-makers' expectations for accurate climate predictions are growing. Natural climate variability, however, poses inherent limits to climate predictability and the related goal of adaptation guidance in many places, as illustrated here for North America. Other locations with low natural variability show a more predictable future in which anthropogenic forcing can be more readily identified, even on small scales. We call for a more focused dialogue between scientists, policymakers and the public to improve communication and avoid raising expectations for…
Publication Type: Journal Article