The United States Forest Service (USFS) bases their wildfire predictions on cloud-to-ground lightning flash density thresholds greater than 5 fl km-2. High flash densities and low precipitation are often emphasized with storms since they are associated with wildfire ignitions. Yet, greater flash rates tend to occur in the areas of greatest rainfall. This study focuses on 95 lightning-initiated wildfires in the western United States during the year of 2017. Lightning data provided by the National Lightning Detection Network (NLDN) were analyzed to determine which strike(s) likely caused each fire, as well as the strikes that did not. Detailed analysis of cloud-to-ground lightning characteristics and thunderstorm characteristics such as stroke density, precipitation rate, and 24-h storm-relative QPE totals are presented. Statistical analyses using a Wilcoxon-Mann Whitney rank sum test were performed to reveal differences between lightning flashes that ignite wildfires and those that do not. Results indicate multiple-stroke negative polarity cloud-to-ground flashes dominated the fire starts. In addition, wildfires were initiated in areas with low stroke densities. Based on these tentative findings, the USFS may need to revisit their methods for wildland fire prediction. Rain rates at the locations of fire starts were 8.03 mm h-1 less than those of non-fire starting flashes, while 24-h QPE totals were 5.28 mm less. These differences were found to be statistically significant. The results of this thesis will help expand the limited knowledge of operational lightning and wildfire meteorology. However, considerable additional research is needed. / A Thesis submitted to the Department of Earth, Ocean and Atmospheric Science in partial fulfillment of the requirements for the degree of Master of Science. / Spring Semester 2019. / March 28, 2019. / Climate Change, Flash Density, Lightning, Precipitation, United States Forest Service, Wildfires / Includes bibliographical references. / Henry Fuelberg, Professor Directing Thesis; Guosheng Liu, Committee Member; Mark Bourassa, Committee Member.

Graduation date: 1991

Thesis (Ph. D.)--University of Queensland, 2001. / Includes bibliographical references.

Based on the author's thesis, State University College of Forestry of Syracuse, N.Y. / Includes bibliographical references (leaves 108-111).

Thesis (Ph. D.)--University of Wisconsin-Madison, 2000. / "UMI no. 9983737"--T.p. verso. Includes bibliographical references (leaves 145-153). Also available on the Internet.

No description available.

In the wildfire community fuel moisture content (FMC) is the quantity of choice when it comes to assess vegetation water status in relation to fire risk and fire behaviour. Field measurements of FMC are both expensive and time consuming and, in addition, sampling is often spatially inadequate. Remote sensing could represent an almost ideal solution both in terms of spatial and temporal coverage, if a consistent relationship between FMC and spectral reflectance could be established. A review of the literature suggests that it is difficult to retrieve FMC for dense forest canopies with remote sensing platforms. This study took a step back and explored the relationship between spectral reflectance and vegetation water content at the leaf level, where several confounding factors present at the canopy level are eliminated or controlled for. It also considered a conifer species, because relatively little research has been produced on this topic for this type of vegetation. The main goal was to establish if FMC can be derived directly from spectral reflectance in the solar spectrum using two well known approaches, such as spectral indices and continuum removal. It is also aimed at exploring if an alternative, indirect way to measure FMC as ratio of Equivalent Water Thickness (EWT) and Specific Leaf Weight (SLW) is feasible and accurate. The results derived from Douglas-fir (Pseudotsuga menziesii (Mirb) Franco) needles used in this study suggested that FMC was not directly retrievable from spectral reflectance but vegetation water content could be assessed with sufficient accuracy in terms of EWT. Also the retrieval of SLW from reflectance of fresh foliage proved to be challenging. Finally, the study also highlighted several aspects in the relationships among foliar water content, dry matter content and reflectance that require additional research. / Graduate

No description available.

Thesis (Ph. D.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on February 28, 2008) Vita. Includes bibliographical references.

Thesis(M.S.)--Auburn University, 2005. / Abstract. Includes bibliographic references.