I. G. McKendry

• PhD
• Professor (Full) at University of British Columbia

A brown air pollution haze that forms over some international cities during the winter has been found to be associated with negative health outcomes and high surface air pollution levels. Previous research has demonstrated a well-established link between the structure of the atmospheric boundary layer (ABL) and surface air quality; however, the deg...

Brown haze, observed over some cities during the winter months, has been found to be associated with poor surface air quality and negative health outcomes. While the link between the atmospheric boundary layer (ABL) structure and surface air quality is well-established, the degree to which boundary layer structure influences local brown haze format...

Accurate measurements of the depth of the convective boundary layer (CBL) are fundamental for understanding and forecasting weather, air quality, and climate. However, the CBL depth (BLD) shows significant spatial and temporal variability, which is challenging to measure and model. Ceilometer instruments, which estimate the CBL depth from aerosol la...

Widespread and persistent summer multi-day episodes of dense wildfire smoke affected western Canada in 2017 and 2018. These events often occurred under otherwise clear-sky, anticyclonic weather conditions and can have significant impacts on surface temperatures, air quality, and surface radiation and energy budgets. Based on upward-pointing lidar o...

The North American Regional Reanalysis (NARR) precipitation product was evaluated using station observations and catchment water yield in British Columbia (BC), Canada, at inter-annual, monthly, and daily time scales. A structural break occurred in 2003, associated with exclusion of Canadian precipitation gauge data from NARR’s data assimilation pr...

A short, but severe, wildfire smoke episode in July 2015, with an aerosol optical depth (AOD) approaching 9, is shown to strongly impact radiation budgets across four distinct land-use types (forest, field, urban and wetland). At three of the sites, impacts on the energy balance are also apparent, while the event also appears to elicit an ecosystem...

A short, but severe, wildfire smoke episode in July 2015, with an aerosol optical depth (AOD) approaching nine, had a significant impact on air quality, radiation and energy budgets across four land use types, and elicited a clear ecosystem response with respect to carbon fluxes at a bog and a forested site. Greatest impacts on radiation and energy...

We describe a model for predicting the moisture content of standardized fuel sticks. Compared to the previously published “Nelson model,” which is the basis for the model currently used by agencies involved with fire management, our model's treatment of moisture diffusion, heat conduction, precipitation interception, and evaporation/sorption proces...

Biomass burning emissions emit a significant amount of trace gases and aerosols and can affect atmospheric chemistry and radiative forcing for hundreds or thousands of kilometres downwind. They can also contribute to exceedances of air quality standards and have negative impacts on human health. We present a case study of an intense wildfire plume...

Transport of coal by train through residential neighborhoods in Metro Vancouver, British Columbia, Canada may increase the possibility of exposure to particulate matter at different size ranges, with concomitant potential negative health impacts. This pilot study identifies and quantifies train impacts on particulate matter (PM) concentrations at a...

Biomass burning emissions emit a significant amount of trace gases and aerosols and can affect atmospheric chemistry and radiative forcing for hundreds or thousands of kilometers downwind. They can also contribute to exceedances of air quality standards and have negative impacts on human health. We present a case study of an intense wildfire plume...

Observations of carbon dioxide (CO2) mixing ratios in the urban boundary layer (UBL) are rare, even though there is potential for such measurements to be used to monitor city-scale net CO2 emissions. This work presents a unique dataset of CO2 mixing ratios observed in the UBL above Vancouver, British Columbia, Canada, by means of a tethered balloon...

Aiming at minimizing the costs, both of capital expenditure and maintenance, of an extensive air-quality measurement network, we present simple statistical methods that do not require extensive training datasets for automated real-time verification of the reliability of data delivered by a spatially-dense hybrid network of both low-cost and referen...

Increasing the amount of fire allowed on the landscape will create more resilient ecosystems but requires a better understanding of the spatial behaviour of wildfires. Fuel moisture is a primary driver of wildfire intensity and is driven by forest floor microclimates. These near­surface conditions can vary substantially across the landscape due to...

Previous research highlights the dominant role of Pacific sea surface temperatures (SSTs) and their associated large-scale teleconnections in modulating the North American monsoon (NAM). At the regional scale, feedbacks associated with land-surface boundary conditions have been shown to provide 'memory' in the system. Here, a previously unexplored...

At Amphitrite Point, ozone (O3) mixing ratios are observed to drop steadily to 5–15 ppb over a period of 12 hours or less with a frequency approaching one event per week (with highest frequencies occurring in summer and fall). Analysis of 47 such O3 depletion events reveals that low O3 episodes are a predominantly nocturnal phenomenon associated wi...

In July and August 2012, a combination of dry weather and record-breaking temperatures led to an unusually intense wildfire season in Boreal Asia. Based on model results and satellite observations it is thought that a portion of the smoke output from these fires was carried across the Pacific to North America in quantities sufficient to adversely a...

A cost efficient technology for accurate surface ozone monitoring using gas-sensitive semiconducting oxide (GSS) technology, solar power and automated cell-phone communications was deployed and validated in a 50 sensor test-bed in the Lower Fraser Valley of British Columbia, over 3 months from May-September 2012. Before field deployment, the entire...

By now, the global impacts of atmospheric dust have been well-established. Nevertheless, relevant properties such as size distribution, depolarization ratio, and even single-scattering albedo have been shown to vary substantially between dust producing regions and are also strongly dependant on the conditions under which the dust is emitted. Even g...

Rust and bunt spores that act as ice nuclei (IN) could change the formation characteristics and properties of ice-containing clouds. In addition, ice nucleation on rust and bunt spores, followed by precipitation, may be an important removal mechanism of these spores from the atmosphere. Using an optical microscope, we studied the ice nucleation pro...

Among the many well-documented cases of springtime trans-Pacific transport of crustal dust from Asia to North America (significant events include those of 1998, 2001, and 2005), the events of March and April 2010 were extraordinary both in the extent of the dust distribution and in the unique meteorological conditions that caused the dust layers in...

Methods to characterize chronic exposure to ultrafine particles (UFP) can help to clarify potential health effects. Since UFP are not routinely monitored in North America, spatiotemporal models are one potential exposure assessment methodology. Portable condensation particle counters were used to measure particle number concentrations (PNC) to deve...

Among the many well-documented cases of springtime trans-Pacific transport of crustal dust from Asia to North America (significant events include those of 1998, 2001, and 2005), the events of March and April 2010 were extraordinary both in the extent of the dust distribution and in the unique meteorological conditions that caused the dust layers in...

A ground-based lidar system that has been deployed in Whistler, British Columbia, Canada, since the spring of 2010 provides a means of evaluating vertical aerosol structure in a mountainous environment. This information is used to help to determine when an air chemistry observatory atop Whistler Mountain (2182 m MSL) is within the free troposphere...

Assuming current emissions and background concentrations, we investigate how changes in synoptic meteorology alone affect ozone episodes in the Lower Fraser Valley, Canada, in future climates. We perform synoptic typing of combined sea level pressure and 500 hPa geopotential heights for June to September 1961- 2000 using the National Centers for En...

In recent decades, the frequency of forest fires has been increasing in western North America (NAW). Several studies have already established a connection between climate oscillations, such as ENSO, and forest fire occurrence. However, a recently discovered variant of El Niño, called El Niño Modoki or Central Pacific El Niño (CP-El Niño), has been...

A mountain air chemistry observatory has been operational on the summit of Whistler Mountain in British Columbia, Canada, since 2002. A 1-yr dataset of condensation nuclei (CN) concentration from this site has been analyzed along with corresponding meteorological data to assess the frequency and patterns of influence from the planetary boundary lay...

CORALNet-UBC was installed in April 2008 as a "proof of concept" and the first facility in a proposed cross-Canada network of similar lidars. Despite its location on the wet West Coast of Canada, data recovery ranged from a low of 45% of the total time in December, when heavy snowfall interrupted operations, to a high of 90% in July. The facility h...

Forest fires in Northern California and Oregon were responsible for two significant regional scale aerosol transport events observed in southern British Columbia during summer 2008. A combination of ground based (CORALNet) and satellite (CALIPSO) lidar, sunphotometry and high altitude chemistry observations permitted unprecedented characterization...

On 30 August 2009, intense forest fires in interior British Columbia (BC) coupled with winds from the east and northeast resulted in transport of a broad forest fire plume across southwestern BC. The physico-chemical and optical characteristics of the plume as observed from Saturna Island (AERONET), CORALNet-UBC and the Whistler Mountain air chemis...

Twenty-six months of continuous ceilometer data are used to estimate the convective mixed-layer height for 710 days by identifying backscatter gradients associated with the entrainment zone. To accomplish this, a semi-automatic procedure is developed that removes all non-applicable data before applying a mixed-layer height algorithm to the backscat...

On 30 August 2009, intense forest fires in interior BC, together with synoptic scale meteorological subsidence and easterly winds resulted in transport of a broad forest fire plume across southwestern BC. The physico-chemical and optical characteristics of the plume as observed from Saturna island (AERONET), CORALNet-UBC and the Whistler Mountain a...

A novel ceilometer validation is presented for a nocturnal elevated PM layer observed over Vancouver, British Columbia. The boundary-layer structure was confirmed by both meteorological and PM vertical profiles. This result is especially significant due to the low PM concentrations present during the observational period (a mean PM<sub align="right...

Aerosols affect climate through scattering and absorption of solar radiation (direct effect) and through their influence on cloud properties (indirect effect). Over the past several decades a wealth of information from ground-based networks, and satellite remote sensing platforms and transport models have helped to better understand aerosol transpo...

Aerosol backscatter measurements from a Vaisala CL31 ceilometer are compared directly with a co-located 532/1064 nm lidar in order to validate the CL31 for remote sensing of vertical aerosol structure. The cases examined include a significant aerosol event (biomass burning), which by virtue of its vertical extent, provides a robust measure of the v...

Several cases of aerosol plumes resulting from trans-Pacific transport were observed between 2 km and 5.3 km at Whistler, BC from 22 April 2006 to 15 May 2006. The fine particle (−3 as measured with a Quadrapole Aerosol Mass Spectrometer (Q-AMS). Coarse particles (>1 μm) were enhanced in all sulphate plumes. Fine particle organic mass concentration...

In urban areas pollutant concentrations are determined by the balance between pollutant emissions, and the state of the atmosphere which determines pollutant transport and dispersion processes. In this chapter we demonstrate that although the nature and characteristics of urban emissions can be variable in time and space, it is changes in pollutant...

The meteorology and physico-chemical characteristics of aerosol associated with two new cases of long range dust transport affecting western Canada during spring 2006 are described. Each event showed enhancements of both sulfate aerosol and crustal material of Asian origin. However, the events were of quite different character and demonstrate the h...

Observations of a plume emanating from a 30-min duration pyrotechnic display with a lidar ceilometer are described for an urban setting in complex, coastal terrain. Advection of the plume across the ceilometer occurred at a mean height of 250m AGL. The plume traveled downwind at ∼3ms−1, and at a distance of 8km downwind, was ∼100m in vertical thick...

An instrumented bicycle was used to elucidate particulate matter exposures along bicycle routes passing through a variety of land uses over 14 days during summer and fall in a mid-latitude traffic dominated urban setting. Overall, exposures were low or comparable to those found in studies elsewhere (mean PM(2.5) and PM(10) concentrations over each...

The meteorology and physico-chemical characteristics of aerosol associated with two new cases of long range dust transport affecting western Canada during spring 2006 are described. Each event showed enhancements of both sulfate aerosol and crustal material of Asian origin. However, the events were of quite different character and demonstrate the h...

1] The first documented case of long-range transport of Saharan dust over a pathway spanning Asia and the Pacific to western North America is described. Crustal material generated by North African dust storms during the period 28 February to 3 March 2005 reached western Canada on 13–14 March 2005 and was observed by lidar and sunphotometer in the V...

A principal component analysis (PCA)-based synoptic typing scheme is used to assess the ability of the Canadian Centre for Climate Modelling and Analysis (CCCma) Coupled Global Climate Model (CGCM2) to reproduce daily mean-sea-level (MSL) synoptic patterns and their frequencies for the Pacific Northwest region of North America. Model output for the...

This study compared 12 variations of regression-based and weighted-average approaches for interpolating daily maximum and minimum temperatures over British Columbia, Canada, a domain with complex topography and highly variable density and elevational distribution of climate stations. The approaches include simple extrapolation with elevation from t...

The remote sensing techniques of Lidar and Sunphotometry are well suited for understanding the optical characteristics of aerosol layers aloft. Lidar has the ability to detect the complex vertical structure of the atmosphere and can therefore identify the existence and extent of aerosols that have undergone long-range transport. Inversion technique...

The adverse public health impacts of anthropogenically derived particulate matter have been well documented, with measurable increases in both morbidity and mortality rates associated with high particulate matter pollution events. Most current research has focussed on the health impacts of anthropogenically derived particulate matter, and there is...

A recent epidemic of mountain pine beetles (MPB) has caused mortality in extensive stands of pine trees in British Columbia, Canada. The epidemic has been attributed, in part, to the recent warming trend in winter in western Canada, as MPB experience mortality during extreme cold spells. This study aimed to clarify the roles of synoptic-scale circu...

During the summers of 2001 and 2002, hourly average ozone concentrations were measured at three sites of differing elevation (188, 588, and 1221 m.a.s.l.) on the forested south-facing slopes of the Lower Fraser Valley (LFV), British Columbia. Sites experienced ozone concentrations ranging from 0 to 88 ppb in 2001, and 0 to 96 ppb in 2002. Daily pat...

In popular usage, the terms “weather pattern” and “weather type” are used variously and often imprecisely to describe states of the atmosphere. An understanding of weather processes and patterns has important applications in such diverse areas as air-quality management, hydrology, water management, human health, forestry, agriculture, energy demand...

In much of North America, variables such as temperature, precipitation, snowpack and streamflow are modulated by modes of large-scale ocean-atmosphere variability such as the Pacific Decadal Oscillation (PDO), El Niõ-Southern Oscillation (ENSO) and the Pacific North American Pattern (PNA). In this study, we test the hypothesis that the influence of...

The original article to which this Erratum refers was published in International Journal of Climatology Volume 26, Issue 4, 2006, 541–560.

A 44-yr climatology of spring Asian dust aerosol emission, column loading, deposition, trans-Pacific transport routes, and budgets during 1960-2003 was simulated with the Northern Aerosol Regional Climate Model (NARCM). Interannual variability in these Asian dust aerosol properties simulated by the model and its climate connections are analyzed wit...

The Northern Aerosol Regional Climate Model (NARCM) was used to construct a 44-yr climatology of spring Asian dust aerosol emission, column loading, deposition, trans-Pacific transport routes, and budgets during 1960 2003. Comparisons with available ground dust observations and Total Ozone Mapping Spectrometer (TOMS) Aerosol Index (AI) measurements...

Turbulence in the very stable nocturnal boundary layer is weak and typically characterized by intermittent bursts of activity. It often exists in isolated layers or pockets generated primarily from localized shear instabilities. As a result, turbulence is rarely in equilibrium with the conditions of the underlying surface. Given the layered structu...

This study describes the application of a novel technique for obtaining vertical profiles (0–400m above ground level) of PM size distributions in a highly polluted setting dominated by domestic burning of wood and coal. At night, smoke from domestic fires is emitted into a highly stable and shallow katabatic flow layer. This layer is only ∼20–40m i...

Size-segregated budgets of soil dust aerosols in Asia for spring 2001 during ACE-Asia were investigated using the NARCM model [Gong et al., 2003b]. Simulated mass size distributions of dust deposition showed a similar size distribution to the dust emission fluxes over the source regions and a decreased peak corresponding to a 1-3 mum diameter range...

The changes in the magnitude and frequency of high intensity rainfall were investigated for the Greater Vancouver Regional District (GVRD). The data on precipitation intensity from five minutes to 24 hours duration for nine GVRD rain gauges and three Meteorological Service of Canada (MSC) rain gauges were gathered. The results show only two station...

The atmosphere is known to episodically transport dust, aerosols, and gaseous pollutants from industrialized east Asia, the Gobi desert, and Siberian wild fires to western North America. We give a novel characterization of the climatological springtime transport from these regions and of the probability of transport ``events,'' that is, long-range...

1] Airborne observations of NMHCs, O 3 , CO, and aerosol scatter were made near the coast of Washington State from 29 March to 6 May 2001 as part of the Photochemical Ozone Budget of the Eastern North Pacific-II (PHOBEA-II) experiment. These observations overlapped the time period of the TRACE-P (24 February to 10 April 2001) and ACE-ASIA (27 March...

A size segregated soil dust emission and transport model NARCM was used to simulate the production and transport of Asian soil dust during the ACE-Asia period from March to May 2001. The model is driven by the NCEP re-analyzed meteorology and has all the atmospheric aerosol processes of soil dust: production, transport, growth, coagulation, and dry...

Since 1997, we have made observations of gases and aerosols along the west coast of the U.S. using ground and airborne platforms. These have been interpreted with trajectories, as well as the GEOS-Chem global chemical transport model, to quantify the influence of upwind sources of ozone, CO and aerosols. From these data we have identified a number...

A novel method for making cost-effective and reliable size-segregated (15 classes in the range 0.3–20 μm) vertical profiles of particulate matter up to 1000 m AGL in the planetary boundary layer is described and evaluated. The performance of a commercial miniature particle mass spectrometer is tested against standard gravimetric and optical instrum...

Chemical measurements of CO, O3, non-methane hydrocarbons, aerosol chemistry, and aerosol scattering in air masses arriving at the west coast of North America demonstrate that a variety of chemical species can be transported across the Pacific from the Eurasian continent. In this paper, we analyze data from several ground sites in the Pacific North...

The relationship between near-surface ozone concentration and the structure of the nocturnal boundary layer was investigated during a field campaign conducted in 1998 in the Lower Fraser Valley (LFV), British Columbia Canada. Despite the spatial and temporal variation in frequency and morphology, secondary nocturnal ozone maxima were shown to be an...

A form of sensitivity analysis is described that illustrates the effects that inputs have on outputs of statistical models. The strength and sign of relationships, the types of nonlinearity, and the presence of interactions between inputs can be diagnosed using this technique. Intended for interpreting flexible nonlinear models, the graphical sensi...

Multi-layer perceptron (MLP) artificial neural network (ANN) models are compared with traditional multiple regression (MLR) models for daily maximum and average O3 and particulate matter (PM10 and PM2.5) forecasting. MLP particulate forecasting models show little if any improvement over MLR models and exhibit less skill than do O3 forecasting model...

As part of the PHOBEA project we made observations of CO, NMHCs, O3 and sub-micron aerosol scattering during the ACE-Asia timeframe, both at the Cheeka Peak Observatory (CPO) in Washington State and using a small plane to get vertical profiles to 6 km. We have used these observations to better understand the ozone-aerosol relationship in this regio...

In spring of 2001 airborne observations of NMHCs, O3, CO and aerosol scatter were made off the coast of Washington State as part of the Photochemical Ozone Budget of the Eastern North Pacific-II (PHOBEA-II) experiment. In this presentation, observations of long-range transport and the springtime background from PHOBEA-II will be evaluated alongside...

An intense Gobi Desert dust storm in April 1998 loaded the midtroposphere with dust that was transported across the Pacific to western North America. The Mesoscale Compressible Community (MC2) model was used to investigate mechanisms causing downward transport of the midtropospheric dust and to explain the high concentrations of particulate matter...

For the first time, long-range transport of ``Kosa'' mineral aerosol from western China to southwestern British Columbia is documented. This late April 1998 event coincided with an episode of photochemical smog and reduced dispersion in the Lower Fraser Valley (LFV). Filter samples in the region show a massive injection of crustal elements (Si, Fe,...

On April 15 and 19, 1998, two intense dust storms were generated over the Gobi desert by springtime low-pressure systems descending from the northwest. The windblown dust was detected and its evolution followed by its yellow color on SeaWiFS satellite images, routine surface-based monitoring, and through serendipitous observations. The April 15 dus...

On April 15 and 19, 1998, two intense dust storms were generated over the Gobi desert by springtime low-pressure systems descending from the northwest. The windblown dust was detected and its evolution followed by its yellow color on SeaWiFS satellite images, routine surface-based monitoring, and through serendipitous observations. The April 15 dus...

Exchange of pollutants between the atmospheric boundary layer and free troposphere is an important (yet often neglected) process that tends to produce distinct layers of pollution in the lower troposphere. These layers represent a potential sink for pollutants from the boundary layer, have the potential to be mixed to ground and likely influence tr...

Three years of hourly averaged PM10 (particulate matter less than 10 microns in diameter) tapered element oscillating microbalance (TEOM) data from 10 sites in the large coastal valley incorporating Greater Vancouver were used to investigate the spatiotemporal dimensions and air pollution meteorology of particulate pollution. During the period stud...

Pre-monsoon principal components (PCs) of circulation fields covering the South Asian subcontinent were used as predictors for all-India summer monsoon rainfall (AISMR) over the period 1958–1993. Predictive skill of non-linear neural network models and linear multiple regression models was compared using a bootstrap-based resampling procedure. Mons...

Pre-monsoon principal components (PCs) of circulation fields covering the South Asian subcontinent were used as predictors for all-India summer monsoon rainfall (AISMR) over the period 1958-1993. Predictive skill of non-linear neural network models and linear multiple regression models was compared using a bootstrap-based resampling procedure. Mons...

Tethersonde, lidar, aircraft, and surface chemistry measurements from an intensive field campaign (Pacific'93) in the Lower Fraser Valley (LFV) demonstrate the daytime advection of pollutants into a lake-filled valley adjoining a broad urbanized coastal valley. On three separate days (immediately before, during, and after a pollutant episode), elev...

Novel use of a commercial, battery-powered, chemiluminescent ozonesonde on a light aircraft is described. This fast-response instrument, originally designed for balloon deployment into the stratosphere, is light, inex- pensive, robust (reuseable), reliable, and accurate. Integration with other lightweight components (data logger, global positioning...

A series of vertical profiles of temperature, relative humidity, NO2 and O3 were determined in the Lower Fraser Valley, British Columbia, as part of the PACIFIC '93 field study. Data from one day show very structured vertical distributions of all parameters in the morning, as expected from the limited vertical mixing under the nocturnal inversion....

Vertical profiling data, including lidar, are used to illustrate elevated layer development during two days of the Pacific '93 field study. Results indicate that multiple processes may produce layers. The “chimney effect”, where pollutants are vented along the heated sidewalls of the valley, is shown to be important, while evidence is also shown fo...

During photochemical air pollution episodes in the Lower Fraser Valley (LFV) near Vancouver, BC, daytime upvalley flows carried polluted air, with high ozone (03) concentrations, into tributary valleys to the north of the LFV. Nighttime flows out of the valleys had low 03 concentrations, according to surface measurements, and also had low aerosol c...

Mixed layer depths were derived from potential temperature profiles from aircraft, high-altitude balloon sonde and tethersonde measurements taken during the Pacific '93 field study in the Lower Fraser Valley of southern British Columbia. In general, mixed layer depths derived from these different data sources were closely comparable. An airborne li...

Desmoplasia, the formation of highly cellular, excessive connective tissue stroma associated with some cancers, shares many features with the wound healing response. Since connective tissue growth factor (CTGF) has previously been demonstrated to play a role in wound repair, we wanted to determine if it might be involved in the pathogenesis of stro...

The objective of this study was to describe the spatial and temporal structure of spring snowpack anomalies in British Columbia, Canada, and to relate the anomaly patterns to climatic fluctuations. Cluster analysis was used to identify relatively homogeneous groups of snow course sites, based on the April 1 snowpack measurements, for the periotd 19...

In order to assess thé ability of a GCM to simulate régional to synoptic scale atmospheric structures, a correlation-ba sed computer-assisted gridded map typing procé- dure is used to compare daily pressure (MSL) and geopotential height fields (500 hPa) front a GCM simulation of thé présent climate to a décade ofNMC analyses. The model is able to r...

The Lower Fraser Valley of British Columbia is currently experiencing rapid population growth and episodically suffers elevated oxidant concentrations, the frequency of which is linked to meteorological conditions on the synoptic scale. This study is a first step toward developing and validating a methodology for `declimatizing' air quality data so...

The Kirchhofer synoptic classification procedure is applied to both mean sea level and 500-hPa NMC gridded pressure fields for the vicinity of southwestern British Columbia. Exceedances of the Canadian 1-h Ambient Oâ Air Quality Objective of 82 ppb at Port Moody, Vancouver, are associated with the coincidence of a low-level thermal trough and an up...

Observations from a transect extending 100 km inland during the Northern Wetlands Study (NOWES) in 1990 show that the sea breeze develops on approximately 25% of days during summer and may penetrate up to 100 km inland on occasions. The sea breeze exhibits a marked diurnal clockwise rotation as a result of the Coriolis effect along the unobstructed...

Analysis of two years of land-based data shows that the Lake Ontario breeze develops on 30% of the days during summer. It typically develops in mid-morning and persists until the lake evening when it is replaced by a well developed land-breeze regime. Simulations of 4 cases with the Colorado State Univeristy mesoscale model show good agreement with...

. Some results of recent research into mesoscale phenomena and climate are reviewed –notably sea breezes, cyclonic eddies, dry lake circulations, urban climates and topoclimates –with particular reference to New Zealand. Extension of this work into modelling and prediction of climate change is likely, and the case for a more integrated geography –o...

Analysis of hourly O3 and NOx data for nine stations for the period 1984–1990 indicates that urban Montreal forms a net sink for O3 in a regional regime characterized by the long-range transport of O3 and its precursors northeastward along the Windsor-Quebec corridor. At central city sites and those adjacent to major transport routes, scavenging of...