The OSIRIS instrument on board the Odin satellite uses limb viewing techniques to measure scattered sunlight and so determine the vertically resolved concentrations of atmospheric constituents including ozone. Initially, a proof of concept instrument was built and tested. This instrument, the Developmental Model, is now housed at the third floor clean room of the Physics Building on the University of Saskatchewan campus. <p> The Developmental Model was incorporated into a system designed to monitor scattered sunlight above Saskatoon. The system was set up to transmit skylight to the Developmental Model using a fiber optic cable and to perform all measurements automatically and with minimal user interaction. The system was calibrated to determine the pixel to wavelength response. Characterizations of the point spread function and relative intensity response of the detector were also made. A shutter system was designed and constructed to measure the detector dark current. An enclosure was built on the top of the Physics Building to provide a weather proof environment and so allow data collection throughout the year. Zenith sky measurements were taken during twilight hours to provide information on the depth of absorption in the Chappuis band, an indicator of the total ozone column. The absorption depth was converted to a Dobson Unit measurement for the ozone column. <p> Analysis of collected data provides two conclusions. The first is that a measurement set in the presence of clouds shows different signatures than a clear measurement set. The second conclusion is the detection of a diurnal trend in the total ozone column with greater amounts measured in the morning. The OSIRIS USASK Observatory is now operational and collecting data for future analysis of scattered sunlight measurements above Saskatoon.

The OSIRIS instrument on board the Odin satellite uses limb viewing techniques to measure scattered sunlight and so determine the vertically resolved concentrations of atmospheric constituents including ozone. Initially, a proof of concept instrument was built and tested. This instrument, the Developmental Model, is now housed at the third floor clean room of the Physics Building on the University of Saskatchewan campus. <p> The Developmental Model was incorporated into a system designed to monitor scattered sunlight above Saskatoon. The system was set up to transmit skylight to the Developmental Model using a fiber optic cable and to perform all measurements automatically and with minimal user interaction. The system was calibrated to determine the pixel to wavelength response. Characterizations of the point spread function and relative intensity response of the detector were also made. A shutter system was designed and constructed to measure the detector dark current. An enclosure was built on the top of the Physics Building to provide a weather proof environment and so allow data collection throughout the year. Zenith sky measurements were taken during twilight hours to provide information on the depth of absorption in the Chappuis band, an indicator of the total ozone column. The absorption depth was converted to a Dobson Unit measurement for the ozone column. <p> Analysis of collected data provides two conclusions. The first is that a measurement set in the presence of clouds shows different signatures than a clear measurement set. The second conclusion is the detection of a diurnal trend in the total ozone column with greater amounts measured in the morning. The OSIRIS USASK Observatory is now operational and collecting data for future analysis of scattered sunlight measurements above Saskatoon.

Simulations of the Atmospheric Emitted Radiance Interferometer (AERI), a ground-based, high-resolution infrared detection system, are used to produce retrieved atmospheric ozone concentration profiles. A line-by-line transmittance model, FASCD3P, is used for the forward model and a maximum likelihood retrieval scheme is employed for the inverse model. An a priori data set consisting of 83 midlatitude winter ozone sondes is used to condition the inversion. Three iterations are required to reduce the radiance residuals to less than the instrument noise. The retrieval accuracy below 300mb is within 25% of truth. Above 300mb, variance within the a priori data is the dominant source of retrieval error. This is due to the number of retrieved layers (27) being higher than the amount of independent information present in the radiance spectra (approximately 4) so much of the retrieval information above 300mb comes from the a priori data.

Banded iron formations (BIFs) are iron oxide- and silica-rich chemical sedimentary rocks and the principal source of high-grade (HG) iron ore. Magnetic survey methods are commonly applied in the exploration for BIF-hosted iron ore deposits but the interpretation of total magnetic intensity (TMI) data is often complicated by the presence of strong remanent magnetization and anisotropy of magnetic susceptibility (AMS). This study evaluated a tri-axial fluxgate vector magnetometer system for ground-based high-resolution mapping of BIF-hosted HG iron ore deposits at a 16 ha site near Mary River, Baffin Island. Magnetometer orientation was measured using a MEMS (Micro Electro-Mechanical System) accelerometer and dual D-GPS receivers. 12-oriented block samples were collected for analysis of rock magnetic properties and supplemented with outcrop measurements using a hand-held susceptibility probe. The large (3 Gauss) dynamic range of the tri-axial vector magnetometer permitted mapping of HG magnetite ore zones, with TMI in excess of 400,000 nT. A 20 m-wide W-E trending HG zone and a narrow (<10 m) BIF zone were identified in RMV maps with distinctive dipole signatures. Within the HG zone a northwest-southeast oriented magnetic fabric was defined by linear magnetic lows that offset the strike of the HG ore zone and were interpreted as brittle faults or shear zones. The RMV orientation indicated the presence of strong bedding parallel magnetization, while its signal amplitude showed a wide variation between ore types and provided basis for ore grade differentiation. Paleomagnetic measurements revealed high Q ratios for hematite ores and strong AMS for BIF. The results from Mary River demonstrate that remanence and AMS effects are important in BIF-hosted iron ores and cannot be neglected in magnetic interpretation and inversion modelling of magnetic source bodies. / Thesis / Master of Science (MSc)

This thesis works through the design of a radar-based system for imaging snowpacks remotely and over large areas to assist in avalanche prediction. The key to such a system is the ability to image volumes of snow at shallow, spatially-varying angles of incidence. To achieve this prerequisite, the design calls for a ground-based Synthetic Aperture Radar (SAR) capable of generating three-dimensional, ultra-high-resolution images of a snowpack. To arrive at design parameters for this SAR, the thesis works through relevant principles in avalanche mechanics, alpine-snowpack geophysics, and electromagnetic scattering theory. The thesis also works through principles of radar, SAR, antenna, and image processing theory to this end. A preliminary system is implemented to test the feasibility of the overall design. The preliminary system demonstrates ultra-high-resolution, three-dimensional imaging capabilities and the ability to image the volume of multiple alpine snowpacks. Images of these snowpacks display the structural patterns indicative of different layers in the snowpacks. Possible attributions of the patterns to physical properties in the snowpack are explored, but conclusions are not arrived at. Finally, lessons from the implementation of this preliminary system are discussed in terms of opportunities to be capitalized upon and problems to be overcome in future systems that more faithfully realize the complete design set forth in the thesis.

Ground-based spectral imaging devices offer an important supplement to satellite imagery. Hand-held, ground-based sensors allow rapid, inexpensive measurements that are not affected by the earth’s atmosphere. They also provide a basis for high altitude spectral indices. We quantified the spectral reflectance characteristics of hard red spring wheat (Triticum aestivum cv. Westbred 936) in research plots subjected to either nitrogen or water stress in a two year study. Both types of stress reduced ground cover, which was evaluated by digital photography and compared with ten spectral reflectance indices. On plots with a similar soil background, simple indices such as the normalized difference vegetation index, ratio vegetation index, and difference vegetation index were equal to or superior to more complex vegetation indices for predicting ground cover. Yield was estimated by integrating the normalized difference vegetation index over the growing season. The coefficient of determination (r2) between integrated normalized difference vegetation index and final yield was 0.86. Unfortunately, none of these indices were able to differentiate between the intensity of green leaf color and ground cover fraction, and thus could not distinguish nitrogen from water stress. We developed a reflective index that can differentiate nitrogen and water stress over a wide range of ground cover. The index is based on the ratio of the green and red variants of the normalized difference vegetation index. The new index was able to distinguish nitrogen and water stress from satellite data using wavelengths less than 1000 nm. This index should be broadly applicable over a wide range of plant types and environments.

This thesis examines a method for estimating the daytime fluxes of heat, water vapour and carbon dioxide at regional scales by using simple models to combine spatially resolved surface properties with bulk meteorological quantities measured at a central location. The central themes of this thesis are that the spatial and temporal variability of regional scale fluxes are contained in the surface properties and meteorology respectively and that the surface properties can be interpolated across a heterogeneous landscape using remotely sensed data. The regional scale fluxes estimated using this technique are compared to the values from three other methods and this allows some conclusions to be made regarding the relative strengths and weaknesses of each method. The surface property approach yields robust estimates of the fluxes that will be useful in researching exchange processes at regional scales, providing input parameters for, and validation of, the biosphere components of General Circulation Models and testing inventory estimates of CO2 budgets. The surface properties are derived using data from 33 aircraft flights and eight ground-based sites along a 96 km transect established during the 1995 Observations At Several Interacting Scales experiment held near Wagga Wagga, New South Wales, Australia. Surface properties examined are the evaporative fraction (ratio of evapotranspiration to available energy), the Bowen ratio (ratio of sensible heat flux to evapotranspiration), the maximum stomatal conductance (maximum stomatal opening under optimal conditions) and the water-use efficiency (ratio of CO2 flux to evapotranspiration). Maximum stomatal conductance is calculated using a simple model of the stomatal response to light and water vapour deficit assuming soil evaporation occurs at the equilibrium rate. The diurnal trend and day-to-day variability in the surface properties is found to be significantly less than the spatial variability. All of the surface properties examined show some sensitivity to the synoptic conditions. The relationships between the surface properties and the Normalised Difference Vegetation Index (NDVI) are examined using a 130 km by 50 km sub-scene from a Landsat 5 Thematic Mapper (TM) image obtained five days before the start of the experiment period. The ground-based and aircraft observations are used to calculate the source-area influencing each measurement and this is combined with the Landsat 5 TM data to produce an average, source-area weighted NDVI for each ground-based site and each aircraft location. The source-area model is important because it provides the link between the observations and the remotely sensed data by identifying the surface patch that influences the measurements. Linear relationships are found between the source-area weighted NDVI and the surface properties. The observed relationships are used to interpolate the surface properties over the region covered by the satellite image and spatial variations in water loss and CO2 uptake by the surface vegetation are identified that are not resolved by the ground-based network. Analysis of the ground-based data showed that the spatial variability of the bulk meteorological quantities used in the surface property approach was much less than the diurnal trend in these data. With the small temporal variation in the surface properties noted before, this confirms the utility of assigning the spatial and temporal variability of the fluxes to the surface properties and the meteorology respectively. The combination of surface properties derived from the aircraft data and meteorology measured at a single location at the centre of the transect shows good skill in predicting the observed fluxes. Furthermore, the discrepancies between the predictions and the observations are explained by the different source-areas of the aircraft and ground-based data and much of the bias is removed when the surface properties are scaled from the NDVI of the aircraft source-area to the NDVI of the ground-based sites. Regional scale fluxes of heat and water vapour calculated using the surface property approach agree with averages of the ground-based data and this indicates that the ground-based network was representative of the OASIS region. Estimates of regional scale CO2 fluxes are not available from the ground-based network due to the lack of measurements at the driest ground-based site but the surface property approach yields plausible values. The results demonstrate the utility of extrapolating surface properties across heterogeneous landscapes using remotely sensed data.

This report is exploring the possibility of characterizing hot Jupiter atmospheres using ground-based high-resolution spectroscopy. The ESO CRIRES infrared spectrometer is selected as the observing tool. Simulated observations are computed for known transiting systems. The properties of observations (noise, spectral coverage, resolution) are estimated with the CRIRES Exposure Time Calculator. An inverse method is used for reconstructing the transmission spectra of exoplanetary atmospheres and identifying spectral features. The possibility of using this method for non-transiting systems is examined. Three exoplanets are deemed possible to reconstruct the spectrum of. / Den här rapporten studerar möjligheten att karaktärisera heta Jupiter atmosfärer genom att använda markbaserad högupplöst spektroskopi. ESO:s CRIRES infraröda spektrometer används som observeringsvektyg. Simulerade observationer beräknas för kända system där planeten genomgår en transit. Flera aspekter kring observationer (brus, våglängdstäckning, upplösning) uppskattas med CRIRES Exposure Time Calculator. En invers metod används för att rekonstruera exoplanetatmosfärers transmissionsspektrum och för att identifiera spektraldrag. Möjligheten att använda den här metoden för system utan transit utforskas. Tre exoplaneter antas vara möjliga att rekonstruera spektrat från.

The ultimate application of this work is constraining the optical properties of cirrus particles, which are poorly understood, by providing an automatic method, using all-sky cameras and an infrared radiometer, to identify the occurrence of the 22° halo formed by cirrus. This is done by interpreting all sky images in terms of a scattering phase function (SPF), from which the halo ratio (HR) is calculated, and by implementing a cirrus detection algorithm to associate HR measures to ice cloud occurrences. Cirrus reflectivity at solar wavelengths is inversely related to the HR which, being an indirect measure of the regularity of the shape of the ice crystals forming the cloud, relates in turn inversely to the asymmetry parameter g. Therefore, the method proposed here to derive statistics of HRs is expected to reduce the uncertainty over the optical and microphysical properties of cirrus. The light intensity measured by the all sky camera is transformed into a scattering phase function, from which the halo formation is identified. This is done by developing image transformations and corrections needed to interpret all sky images quantitatively in terms of scattering phase function, specifically by transforming the original image from the zenith-centred to the light-source-centred system of coordinates and correcting for the air mass and for vignetting. The SPF is then determined by averaging the image brightness over the azimuth angle and the HR by calculating the ratio of brightness at two scattering angles in the vicinity of the 22° halo peak. The instrument transformation and corrections are performed using a series of Matlab scripts. Given that the HR is an ice cloud characteristic and since the method needs additional temperature information if the halo observation is to be associated with cirrus, a cirrus detection algorithm is necessary to screen out non-ice clouds before deriving reliable HR statistics. Cloud detection is determined by quantifying the temporal fluctuations of sky radiance, expressed as brightness temperature (BT), through De-trended Fluctuation Analysis and setting a clear sky fluctuation threshold. Cloud phase discrimination instead is achieved through first constructing an analytic radiative transfer model to obtain an estimate for average molecular absorption cross-section of water vapour within the spectral window of the radiometer. This is done to model the down-welling clear sky radiance, which is in turn used to correct cirrus emissivity and ultimately determine a dynamic BT threshold for the transition from ice to liquid-containing clouds. In addition to the molecular cross section the screen level air temperature and integrated water vapour are used as input parameters to the model. The utilisation of the all sky camera for such quantitative measurement was the particularly novel aspect of this work; this has not been done previously to the best of my knowledge. The cirrus detection method proposed is also innovative in that with respect to previous works it does not rely on the use of additional techniques such as LIDAR or microwave radiometry for discriminating cloud phase. Furthermore, the cirrus threshold proposed is not fixed but accounts for the attenuating properties of the atmosphere below the cloud. Once the cirrus detection algorithm is validated and cirrus occurrences determinable, the HR could be extended to estimating the asymmetry parameter and crystal roughness. These are retrievable, for instance, from in-situ observations of single ice crystal 2D scattering patterns from cloud probes of the SID (Small Ice Detector) type. This would be significant for the constraining of the optical and microphysical properties of cirrus.

Terrestrial Radar Interferometry (TRI) is a relatively new ground-based technique that combines the precision and spatial resolution of satellite interferometry with the temporal resolution of GPS. Although TRI has been applied to a variety of fields including bridge and landslide monitoring, it is ideal for studies of the highly-dynamic terminal zones of marine-terminating glaciers, some of which are known to have variable velocities related to calving and/or ocean-forced melting. My TRI instrument is the Gamma Portable Radar Interferometer, which operates at 17.2 GHz (1.74 cm wavelength), has two receiving antennas for DEM (digital elevation model) generation, and images the scenes at minute-scale sampling rates. Most of this TRI work has focused on two glaciers: Breiðamerkurjökull in Iceland and Helheim in Greenland. Monitoring the displacement of stationary points suggests velocity measurement uncertainties related to the instrument and atmosphere of less than 0.05 m/d. I show that the rapid sampling rate of the TRI can be used to observe velocity variations at the glacier terminus and assess the impact and spatial distribution of tidal forcing. Additionally, iceberg tracking in the amplitude imagery may provide insight about ocean currents near the terminus.