Research Fields

Atmospheric Science and Meteorology

Severe Weather Dynamics and Prediction

Dr. Chen’s research interests are in studying the dynamics of severe weather phenomena, in particular hurricanes and convective storms, and in improving their predictions. Specific topics such as cyclogenesis, rapid intensity change, mesoscale structures of hurricanes, the initiation and evolution of severe storms, and their interactions with the synoptic-scale and smaller-scale flows are investigated through observations and numerical modeling. Advanced multi-scale data assimilation techniques are designed and utilized not only as powerful research tools, but also as methods to improve severe weather predictions by assimilating critical in-situ and remote-sensing observations into the models.

Modelling of Atmospheric Dynamics

Vorticity Dynamics and Thermodynamics: Dr. Jenkins's research involves the vorticity dynamics and thermodynamics of meso- and synoptic-scale circulation systems; time series and data analyses of the climatology of the Northern Hemisphere; numerical investigations into the mechanisms responsible for increased surface COs concentrations in Arctic regions; numerical investigations into the mechanisms responsible for the snow-belt north of Lake Ontario; forest-fire-meteorology numerical modelling.

Dr. Klaassen's major research interests are in wave dynamics, stratified shear flows, the transition to turbulence, cloud dynamics and mesoscale meteorology. A variety of theoretical and numerical models are being employed to study the evolution and stability of nonlinear disturbances in the atmosphere. The goal is to improve our understanding the evolution of complex small scale flows, and their interactions with the larger scales associated and weather and climate systems. These issues will become increasingly important over the next few years as hydrostatic global and regional models are pushed to finer resolution, and will be especially important in the development of nonhydrostatic global circulation and weather prediction models. Small-scale processes also represent fascinating examples fundamental problems in fluid dynamics.

Recently, Dr. Klaassen's group has focused on gravity wave processes in the atmosphere, including gravity wave generation, propagation and breaking. We are also developing parameterization schemes for the representation of drag due to small-scale unresolved gravity waves, a process which is of crucial importance in determining the circulation of the middle atmosphere and its effect on ozone. This work is also relevant to other stably stratified geophysical flows, e.g., the ocean. Other areas of interest include moist convection, and the transition to turbulence in shear flows.

Chemical and Dynamical Modelling of Atmospheres Dr. McConnell's group is currently studying the photochemistry and transport of species of tropospheric and stratospheric interest using 0-D, 1-D and 3-D transport models. Among the problems currently being addressed are the cause of the springtime decrease in polar ozone, the impact of aerosols on global ozone decrease and also the increase of tropospheric gases such as ozone, methane and carbon monoxide over the last century or the oxidation capacity of the atmosphere. The group also studies radiative transfer modelling of the upper atmospheres and ionospheres of the Earth and outer planets using the data from the Voyager flyby, IUE and ground based telescopes.

Dr. Peter Taylor's research pertains to the lowest layers of the atmosphere, from the surface to heights of about 1000m. This layer is studied using numerical models and field observations. Specific interests are in the study of flow over hills and in complex terrain, stable boundary layers, blowing snow and aspects of air-sea interaction including wind wave generation. Wind tunnel studies and the use of networks of automated surface weather stations have also been undertaken

External academic recognition of York University through the Department of Earth and Space Science and Engineering  was achieved in 1996 when York became a member of the University Corporation for Atmospheric Research (UCAR) who operate NCAR, the U.S. National Center for Atmospheric Research in Boulder, Colorado.

York is now the third Canadian university to acquire membership in UCAR. Recognition such as this denote the academic strength in the Department of Earth and Space Science and Engineering and provides a beneficial association between UCAR and York University.

Earth Science and Geomatics Engineering

Research in Dr. Aldridge's group centres on the application of laboratory studies of long-period fluid oscillations to the excitation and detection of these modes in the Earth's fluid outer core. Non-linear and viscous effects, observed in laboratory experiments but ignored in present theory for such modes, play a central role in the identification of core modes in the superconducting gravimetric data. Furthermore, coupling between fluids and their containers has suggested the use of VLBI (Very Long Baseline Interferometry) as a tool to detect core oscillations and initial results from our analysis of some NGS/NOAA data appear promising.

Photogrammetry

Dr. Armenakis’ research interests are in the areas of rapid and on-time mapping and monitoring methods and technology using imaging and ranging data. Current research areas include: a) the development and use of low-cost unmanned aerial mapping systems (UMAS) and mobile mapping systems for rapid mapping, monitoring and tracking to explore their potential and reliability in operational environments; and b) the development of methods and technology for spatial feature extraction, terrain modelling and spatio-temporal change detection and extraction from imaging and ranging data using photogrammetric, remote sensing and GIS methods.

Global Navigation Satellite Systems

Dr. Bisnath's research interests centre about the use of Global Navigation Satellite Systems (GNSSs), most notably GPS, for a multitude of precise positioning and navigation applications. Specific application areas include crustal deformation monitoring, precise orbit determination, and precise positioning of offshore platforms. This research requires development of positioning algorithms, which include filters, functional models, stochastic models, and prediction models to mitigate physical affects. Recent algorithm research has focused on improving the robustness of precise point positioning, and extending the range of single-baseline, real-time kinematic (RTK) GPS.

Geographical Information Systems

Dr. Cheng is interested in spatial analysis of earth and environmental systems. His research group is involved in the development and application of geographical information systems (GIS) for mineral exploration and natural resources assessment. Current research projects include: (1) Development of GIS Integrated Stochastic and Multifractal Techniques for Spatial and Dynamic Modelling and Prediction of Mineral Deposits and Water Resources; (2) fractal/multifractal modelling of resolution dependence of remote sensing and geographic data; (3) Spatial/Spectrum/Multifractal analysis for pattern recognition; and (4) Graphic Interfaced Programming in VB, VC++ and Active X.

Remote sensing

Dr. Hu's research interests include canopy reflectance modelling, deriving biophysical parameters of forest canopies from remote sensing data, hyperspectral remote sensing, image processing, and photogrammetry.

Geodynamics and Mantle Convection

Dr. Jarvis' research interests lie in the field of Geodynamics. He employs computer intensive numerical models to study the temperature and velocity fields in the solid outer 3,000 km of the Earth's interior. This research addresses the problem of the driving force for plate tectonics and continental drift. Numerical studies of the causes and consequences of continental collisions, aggregation and dispersal form a part of this research. It involves the use of microcomputers, UNIX workstations and supercomputers.

Methodologies for Optical Earth Observations

Dr. John Miller is engaged in research related to the use of physical models for the quantitative interpretation of high spectral resolution digital image data from airborne and satellite sensors. Research methods involve the use of field spectrometers, solar radiometers, and airborne digital data collection with the Compact Airborne Spectrographic Imager (CASI), with image analysis using hyperspectral image analysis software. Problems investigated include: atmospheric correction of image data to surface reflectances, interpretation of water colour spectra in terms of constituent concentrations and extraction of forest canopy information on biochemical constituents and canopy architectural parameters.

Dynamics of the Earth as Observed by Geodetic Techniques

Dr. Spiros Pagiatakis is interested in the dynamics of the Earth, both in global and regional/local scales, as observed by geodetic techniques. On-going research includes the determination of the glacial isostatic adjustment signature from more than 50 years of terrestrial gravity observations in Canada and GRACE gravity mission level-2 data. Research interests also expand in the area of physical geodesy, and in particular in the determination of the geoid (local and global scales) and of the sea surface topography. Other research activities include the study of the response of the Earth to ocean tide loading, spectral methods and their application to the analyses of superconducting gravimeter (GWR), Very Long Baseline Interferometry (VLBI) and GPS time series.

Global Earth Dynamics and Space Measurement Techniques

Dr. Smylie is interested in global earth dynamics and space measurement techniques applied to geophysics. Ongoing work includes studies of the long period oscillations of the Earth's fluid outer core, and their detection through Very Long Baseline Interferometric techniques and superconducting gravimeter data. Modes which exchange angular momentum with the solid parts of the Earth appear in the new, very accurate VLBI measurements of the spin rate, polar motion and nutation. Other modes register as small gravimetric signals. The new Canadian gravimeter facility and data from collaborating installations around the globe is used in this research.

Remote Sensing and Geodynamics

Dr. Szeto's current research focuses on remote sensing. In particular he explores efficient mans of interpreting Synthetic Aperture Radar data. His interests of longer term standing lie in global geophysical phenomena, especially those pertaining to the solid inner core and fluid outer core. These include (1) the role of the inner core in geodynamics theory, (2) dynamical motion of the inner core, (3) how core structure influences the Earth's rotation, nutation and wobble. Potential students should have an affinity towards physics, mathematics and computing.

Integrated Navigation and High Accuracy & Precision Engineering Surveying

Dr.-Ing. Wang's research interests centre about the applications of Integrated Navigation and High Accuracy & Precision Engineering Surveying. Good example for Integrated Navigation is multi-sensor systems, the core of modern direct-georeferencing systems that integrate the GNSSs, Inertial sensors, and any other positioning & orientation sensors available. The research in this area innovates and develops advance algorithms including error modeling, Kalman filtering, robust filtering, system simulation, hardware integration, and real-time & post-processing SW development. High Accuracy & Precision Engineering Surveying engages special engineering surveying applications such as deformation monitoring and industrial surveying.

Space Science and Space Engineering

Space Systems Engineering, Space Physics and Space Instrumentation

Dr. Yunlong Lin’s research interests are design,integration, test and operation of modern small satellites or small space systems; the space environment and its effects: monitoring, testing, simulation, protection and mitigation; space payloads for Earth and its atmospheric observations, lunar industry initiative and planetary exploration.

Aeronomy of the Earth's Upper Atmosphere

Dr. McDade's research activities are primarily in the areas of optical aeronomy and space physics. He uses UV, visible and near-IR spectrophotometric observations made from rockets, satellites and ground observing stations to study photochemical processes that produce light in the upper atmosphere. His research focuses on attempts to understand the physics and chemistry of these processes and the development of remote sensing techniques which exploit these optical airglow emissions to study the composition, energetics and dynamics of the upper atmosphere.

Space engineering and planetary physics

Dr. Quine's primary research focuses on the development of optical instrumentation, analysis techniques and space test processes to advance planetary research and to improve the performance and reliability of space systems. He is the principal investigator for Northern Light, a proposed Canadian mission to lander on the surface of Mars this decade. He is also co-investigator for the MANTRA balloon missions to assess the odd nitrogen chemistry in the stratosphere and a co-investigator for the Can-X Pico-satellite facility. His research can be divided into three principle scientific themes: Earth observation, Mars Exploration and the observation of Extrasolar planetary systems. These initiatives involve the development of both theoretical analysis tools to design instrumentation and to retrieve information from observation data and the development of the hardware needed to make space-based measurements.

Spacecraft dynamics

Dr. Shan's research interests include Spacecraft Dynamics, Control and Navigation; Active Vibration Control; Formation Flying (Flight); Airship Development; Cooperative and Coordinated Control of Multiple Vehicles; and Ground-Based Testbed Development.

Dynamical Processes in the Upper Atmosphere

Dr. Shepherd is Principal Investigator for Canada's Wind Imaging Interferometer (WINDII), in orbit since September 12, 1991, on NASA's Upper Atmosphere Research Satellite (UARS), which is still acquiring data. Using these data he studies winds and temperatures using photochemically produced "airglow" emissions as a target, for the altitude range 80 to 300 km. The emission strength also provides information on the concentration of atomic oxygen, an important constituent in the upper atmosphere. It has been learned that the atomic oxygen is strongly affected by planetary scale waves in the atmosphere, and by atmospheric tides. Ground-based instruments are also operated remotely, near Toronto and at Resolute Bay, in the Canadian Arctic. Work is in progress on new missions to measure winds in the mesosphere (45 to 85 km), and in the stratosphere (20 to 45 km). The latter will provide important information on ozone and its transport, and may improve weather forecasts.

Atmospheric Lidar

Dr. Whiteway's research interests can be subdivided into a number of categories. Atmospheric measurements: The main technical basis of the research is development and application laser remote sensing (or lidar) for atmospheric measurements from the ground, from aircraft, and on Mars. Much of the research also involves in-situ measurements with instruments installed on a high altitude aircraft called the Egrett. Climate: Airborne measurement campaigns to study cirrus clouds, water vapour, and dynamics in the upper troposphere at mid-latitudes and in the tropics. Atmospheric Dynamics: Airborne measurement campaigns to investigate atmospheric gravity waves and turbulence. Martian Atmosphere: Design, testing, and implementation of a lidar system on the Phoenix Mars Lander (2008) to measure the distribution of dust and clouds. Air Quality: Development of a mobile lidar and measurements to investigate the sources and evolution of urban pollution. Arctic Ozone: Construction of a new lidar for measurements of tropospheric and stratospheric ozone at the Eureka Station in the Canadian Arctic.

Mechanics

Dr. Zhu's research interest can be subdivided into a number of categories. Fundamental: computational solid mechanics; nonlinear finite element analysis and design evaluation; cable dynamics; vehicle dynamics; structural mechanics; fatigue, fracture and damage mechanics; computer simulation; dynamics and control of mechanical systems; residual Stress and welding engineering. Aerospace: dynamics and control of aerial refueling hose and drogue, towed instruments. Aircraft/ship dynamic interface analysis. Motion measurement using photogrammetry. Defence: naval shock analysis and design; dynamics and control of underwater towed vehicles. Robotics: kinematics; dynamics; automated aircraft passenger bridge.