Evaluation of NARCM using aircraft observation from NARE

The Northern Aerosol Regional Climate Model (NARCM) is being developed in order to better understand how aerosols affect the Canadian climate. NARCM uses microphysical and chemical parameterizations that enable it to predict the evolution of the aerosol spectrum using the concentration and composition in 12 size-segregated bins as prognostic variables. In this study, two aerosol species are considered as prognostic variables within NARCM: sulphate and sea-salt. The sulphur species concentrations and aerosol distributions simulated by NARCM are evaluated against clear-sky in-situ aircraft measurement taken off the coast of Nova Scotia during the North Atlantic Regional Experiment (HARE). NARCM demonstrates skill at predicting the column burdens of the sulphur species concentrations at the NARE site throughout the NARE period. Simulations of the average column burdens of sulphur dioxide and sulphate showed differences of 57% and 28% respectively from the observed values. The accumulation mode in the aerosol distributions simulated by NARCM has a tendency to be smaller than the measured mode. There is evidence that the absence of other aerosol species may account for the too small sizes of the simulated aerosol when sulphate volumes are small

Setting the Stage for Discussion - 23RD ANNUAL JOHN K. FRIESEN CONFERENCE "Housing Alternatives for an Aging Population" May 28-29, 2014

This video comprises an address to the attendees of the 23rd Annual John K. Friesen Conference, "Housing Alternatives for an Aging Population" held May 28-29, 2014, Vancouver, BC. The Simon Fraser University Gerontology Research Centre (GRC) and associated Gerontology Department are pleased to welcome you to the 23rd John K. Friesen Conference. This year’s conference, organized and hosted in cooperation with the Lifelong Learning Adults 55+ Program, explores a range of tenure arrangements, housing forms, and service models currently available and under development for adults 55+ in British Columbia, including cohousing popular in the USA; life-lease projects, popular in the prairie provinces; mixed-tenure models and models targeted to specific groups (e.g., Performing Arts Lodges; ethno-cultural housing). Assisted Living was discussed as well as housing and service options that do not require people to move from their current home (e.g., the Village Model, United Way’s Better at Home Program, retro-fitting or adding “smart” technologies). Keynote speakers, expert panels and poster presentations discussed the pros and cons of each housing option and the type of resident for whom it is best suited. The objective of the conference was to provide information that enable people aged 55+ to plan ahead and make informed choices. As well, it was designed to provide a forum for developers (private, public & non-profit) to learn what adults aged 55+ are looking for in the way of housing for their later years. Sponsors: Canada Mortgage and Housing Corporation; BC Housing; Retirement Concepts We also gratefully acknowledge a grant from the SFU Library\u27s Scholarly Digitization Fund for videography and post-production editing

Development of visibility forecasting modeling framework for the Lower Fraser Valley of British Columbia using Canada’s Regional Air Quality Deterministic Prediction System

<p>Visibility degradation, one of the most noticeable indicators of poor air quality, can occur despite relatively low levels of particulate matter when the risk to human health is low. The availability of timely and reliable visibility forecasts can provide a more comprehensive understanding of the anticipated air quality conditions to better inform local jurisdictions and the public. This paper describes the development of a visibility forecasting modeling framework, which leverages the existing air quality and meteorological forecasts from Canada’s operational Regional Air Quality Deterministic Prediction System (RAQDPS) for the Lower Fraser Valley of British Columbia. A baseline model (GM-IMPROVE) was constructed using the revised IMPROVE algorithm based on unprocessed forecasts from the RAQDPS. Three additional prototypes (UMOS-HYB, GM-MLR, GM-RF) were also developed and assessed for forecast performance of up to 48 hr lead time during various air quality and meteorological conditions. Forecast performance was assessed by examining their ability to provide both numerical and categorical forecasts in the form of 1-hr total extinction and Visual Air Quality Ratings (VAQR), respectively. While GM-IMPROVE generally overestimated extinction more than twofold, it had skill in forecasting the relative species contribution to visibility impairment, including ammonium sulfate and ammonium nitrate. Both statistical prototypes, GM-MLR and GM-RF, performed well in forecasting 1-hr extinction during daylight hours, with correlation coefficients (<i>R</i>) ranging from 0.59 to 0.77. UMOS-HYB, a prototype based on postprocessed air quality forecasts without additional statistical modeling, provided reasonable forecasts during most daylight hours. In terms of categorical forecasts, the best prototype was approximately 75 to 87% correct, when forecasting for a condensed three-category VAQR. A case study, focusing on a poor visual air quality yet low Air Quality Health Index episode, illustrated that the statistical prototypes were able to provide timely and skillful visibility forecasts with lead time up to 48 hr.</p> <p><i>Implications</i>: This study describes the development of a visibility forecasting modeling framework, which leverages the existing air quality and meteorological forecasts from Canada’s operational Regional Air Quality Deterministic Prediction System. The main applications include tourism and recreation planning, input into air quality management programs, and educational outreach. Visibility forecasts, when supplemented with the existing air quality and health based forecasts, can assist jurisdictions to anticipate the visual air quality impacts as perceived by the public, which can potentially assist in formulating the appropriate air quality bulletins and recommendations.</p

Impacts of the July 2012 Siberian fire plume on air quality in the Pacific Northwest

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 from Siberia that affected the air quality across the Pacific Northwest on 6&ndash;10 July 2012. Using satellite measurements (MODIS True Colour RGB imagery and MODIS AOD), we track the wildfire smoke plume from its origin in Siberia to the Pacific Northwest where subsidence ahead of a subtropical Pacific High made the plume settle over the region. The normalized enhancement ratios of O3 and PM1 relative to CO of 0.26 and 0.08 are consistent with a plume aged 6&ndash;10 days. The aerosol mass in the plume was mainly submicron in diameter (PM1 ∕ PM2.5 = 0.96) and the part of the plume sampled at the Whistler High Elevation Monitoring Site (2182 m a.s.l.) was 88 % organic material. Stable atmospheric conditions along the coast limited the initial entrainment of the plume and caused local anthropogenic emissions to build up. A synthesis of air quality from the regional surface monitoring networks describes changes in ambient O3 and PM2.5 during the event and contrasts them to baseline air quality estimates from the AURAMS chemical transport model without wildfire emissions. Overall, the smoke plume contributed significantly to the exceedances in O3 and PM2.5 air quality standards and objectives that occurred at several communities in the region during the event. Peak enhancements in 8 h O3 of 34&ndash;44 ppbv and 24 h PM2.5 of 10&ndash;32 µg m−3 were attributed to the effects of the smoke plume across the Interior of British Columbia and at the Whistler Peak High Elevation Site. Lesser enhancements of 10&ndash;12 ppbv for 8 h O3 and of 4&ndash;9 µg m−3 for 24 h PM2.5 occurred across coastal British Columbia and Washington State. The findings suggest that the large air quality impacts seen during this event were a combination of the efficient transport of the plume across the Pacific, favourable entrainment conditions across the BC interior, and the large scale of the Siberian wildfire emissions. A warming climate increases the risk of increased wildfire activity and events of this scale reoccurring under appropriate meteorological conditions

Use of multiple tools including lead isotopes to decipher sources of ozone and reactive mercury to urban and rural locations in Nevada, USA

Ambient air particulate matter (&lt;2.5μm in diameter) samples were collected on two different filter types in 2014 and 2015 over 24h periods and analyzed for reactive mercury (gaseous oxidized mercury+particulate bound mercury) concentrations and lead isotopes to determine sources of pollution to three sites in Nevada, USA. Two sites were located on the western edge of Nevada (Reno, urban, 1370m and Peavine Peak, rural, high elevation, 2515m); the third location was ~485km east in rural Great Basin National Park, NV (2061m). Reactive mercury samples were collected on cation exchange membranes simultaneously with lead samples, collected on Teflon membranes. Lead isotopic ratios have previously identified trans-Pacific lead sources based on the 206/207 and 208/207 lead ratios. Influence from trans-Pacific air masses was higher from March to June associated with long-range transport of pollutants. Spring months are well known for increased transport across the Pacific; however, fall months were also influenced by trans-Pacific air masses in this study. Western North American background ozone concentrations have been measured and modeled at 50 to 55ppbv. Median ozone concentrations at both rural sites in Nevada were within this range. Sources leading to enhancements in ozone of 2 to 18ppbv above monthly medians in Nevada included emissions from Eurasia, regional urban centers, and global and regional wildfires, resulting in concentrations close to the USA air quality standard. At the high elevation locations, ozone was derived from pollutants being transported in the free troposphere that originate around the globe; however, Eurasia and Asia were dominant sources to the Western USA. Negative correlations between reactive mercury and percent Asian lead, Northern Eurasia and East Asia trajectories indicated reactive mercury concentrations at the two high elevation sites were produced by oxidants from local, regional, and marine boundary layer sources