Spatial patterns of humidity, fuel moisture, and fire danger across a forested landscape
department or school: Arts, Faculty of
department or school: Geography, Department of
data provider: DSpace
degree campus: UBCV
creator: van der Kamp, Derek W.
issued: 2017-08-30T22:35:22Z
issued: 2017
related degree: Doctor of Philosophy - PhD
degree grantor: University of British Columbia
description: Spatial variability in fuel moisture driven by changes in microclimate is an important bottom-up factor determining spatial wildfire behaviour, as fuel moisture impacts fire intensity, severity, and spread probability. However, few studies have examined how landscape scale patterns in near-surface microclimates impact fuel moisture patterns. This study quantified patterns of near-surface atmospheric conditions within a heterogeneous forested landscape, and determined how those patterns impact the spatial variability of fuel moisture and fire danger across the landscape. Observations across a forested landscape demonstrated that, in general, spatial variability in near-surface relative humidity and temperature was highest during dry, clear-sky conditions. However, daytime relative humidity was an exception, being relatively homogenous across the landscape and only weakly related to weather conditions. Canopy cover and above-canopy radiation load predicted a significant portion of the spatial patterns in relative humidity and temperature. Changes in canopy cover had the largest impact on near-surface conditions. Open sites saw higher relative humidity, on average, due to nocturnal longwave cooling. A novel fuel moisture model was presented that predicted between 76% and 93% of the variance in observations from independent sites or time periods, which is an improvement on a more complex model currently used operationally. This model was combined with meteorological observations to quantify spatial patterns in fuel moisture and potential fire danger across the landscape. Daytime fuel moisture and potential fire danger exhibited low spatial variability, regardless of weather conditions, and only 1-hour fuel moisture was related to canopy cover or radiation load. Fuel moisture and potential fire danger were more variable at night and that variability increased during cool, moist periods with low wind speeds. Patterns in fuel moisture and potential fire danger were dominat…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/62891
note: Spatial patterns of humidity, fuel moisture, and firedanger across a forested landscapebyDerek W. van der KampBSc., Physics and Ocean Sciences, University of Victoria, 2005MSc., Geography, The University of British Columbia, 2008A THESIS SUBMITTED IN PARTIAL FULFILLMENTOF THE REQUIREMENTS FOR THE DEGREE OFDoctor of PhilosophyinTHE FACULTY OF GRADUATE AND POSTDOCTORALSTUDIES(Geography)The University of British Columbia(Vancouver)August 2017c© Derek W. van der Kamp, 2017AbstractSpatial variability in fuel moisture driven by changes in microclimate is an im-portant bottom-up factor determining spatial wildfire behaviour, as fuel moistureimpacts fire intensity, severity, and spread probability. However, few studies haveexamined how landscape scale patterns in near-surface microclimates impact fuelmoisture patterns. This study quantified patterns of near-surface atmospheric con-ditions within a heterogeneous forested landscape, and determined how those pat-terns impact the spatial variability of fuel moisture and fire danger across the land-scape. Observations across a forested landscape demonstrated that, in general,spatial variability in near-surface relative humidity and temperature was highestduring dry, clear-sky conditions. However, daytime relative humidity was an ex-ception, being relatively homogenous across the landscape and only weakly relatedto weather conditions. Canopy cover and above-canopy radiation load predicteda significant portion of the spatial patterns in relative humidity and temperature.Changes in canopy cover had the largest impact on near-surface conditions. Opensites saw higher relative humidity, on average, due to nocturnal longwave cooling.A novel fuel moisture model was presented that predicted between 76% and 93%of the variance in observations from independent sites or time periods, which is animprovement on a more complex model currently used operationally. This modelwas combined with meteorological observations to quantify spatial pattern…
has type: Thesis/Dissertation
date issued: 2017-11
is shown at: 10.14288/1.0355217
language: eng
degree discipline: Geography
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivatives 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-nd/4.0/
scholar level: Graduate
type: Text
identifier URI: http://hdl.handle.net/2429/62891