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Western University

Remote sensing

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Full-Text Articles in Physical Sciences and Mathematics

Airborne Observations Of Thermal Anisotropy From Urban Residential Neighbourhoods In Salt Lake City, Utah, Samantha J. Claessens Jun 2020

Airborne Observations Of Thermal Anisotropy From Urban Residential Neighbourhoods In Salt Lake City, Utah, Samantha J. Claessens

Electronic Thesis and Dissertation Repository

Urban surface temperatures are important variables in urban climatological processes. This thesis examines the directional variability of remotely sensed urban surface temperatures (thermal anisotropy or Λ) for three vegetated residential neighbourhoods in Salt Lake City, Utah, USA. Airborne thermal remote sensing using a thermal imager sampled the directional brightness temperature (DBT) at three times within a day for each site. Results indicate that temporal variability over a 20 – 30-minute flight was not negligible. Average DBT were then extracted from atmospherically corrected images and plotted on polar plots. For low density residential neighbourhoods Λ is increased with increasing tree-canopy coverage …

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Optimal Algorithms For Deriving Estimates Of Phytoplankton Biomass In Lakes From Landsat Satellite Imagery, Michael A. Dallosch Apr 2019

Optimal Algorithms For Deriving Estimates Of Phytoplankton Biomass In Lakes From Landsat Satellite Imagery, Michael A. Dallosch

Electronic Thesis and Dissertation Repository

The frequency, intensity, and geographical distribution of harmful phytoplankton blooms are on the rise globally. There is a scientific need for estimates of historical and current phytoplankton data. This research develops mathematical algorithms for accurate assessment of surface chlorophyll-a (chl-a), a proxy for phytoplankton biomass, within freshwater lakes. Landsat satellite images (4-5 TM, 7 ETM and 8 OLI) were used to create predictive models (from 1984 to 2017) for seven ecoregions (ranging from the tropics to arctic). Correlation tests for 82 algorithms were conducted to establish the best fit models (linear, exponential, logarithmic, power) for chl-a …

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The Effect Of Sub-Facet Scale Geometry On Vertical Facet Temperatures In Urban Street Canyons, Rainer V.J. Hilland Oct 2018

The Effect Of Sub-Facet Scale Geometry On Vertical Facet Temperatures In Urban Street Canyons, Rainer V.J. Hilland

Electronic Thesis and Dissertation Repository

Surface temperature plays a key role in many micro-scale urban processes. Walls comprise a significant percentage of the urban surface, yet are under-represented by many methods of thermal remote sensing and not considered in detail by micro-scale surface temperature mod- els. This thesis presents a novel method of mobile thermal observation performed in urban street canyons in London, ON that uses a thermal imager as well as a visual spectrum camera to provide dense spatial and temporal resolution of micro-scale wall temperature distributions. Images are manually classified by a series of nominal variables and the resulting data set discusses the …

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Exploration Of Spatial And Temporal Changes In Trophic Status Of Lakes In The Northern Temporal Forest Biome Using Remote Sensing, Aleksey Paltsev Apr 2015

Exploration Of Spatial And Temporal Changes In Trophic Status Of Lakes In The Northern Temporal Forest Biome Using Remote Sensing, Aleksey Paltsev

Electronic Thesis and Dissertation Repository

There is a critical need for detailed surveys of lakes covering large spatial (>100 km2) and temporal scales (decades) to determine if there is an increase in the magnitude and frequency of phytoplankton blooms. Remote sensing was used to: (1) develop a regression model that relates chlorophyll a (chl-a) as a proxy of lake phytoplankton biomass to Landsat TM and ETM+ optical reflectance (r2=0.85, p

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