Space-time UFP and BC models for different geographical areas

Abstract

Until recently few models existed to assess spatio-temporal variation of ultrafine particles (UFP) and Black carbon (BC). A major complication is the lack of routine monitoring data for these components in many areas. A review of UFP and BC modeling studies was conducted, distinguishing modeling of long-term average spatial contrasts and shorter-term averages (24 hour or less). Dispersion models and geo-statistical models based on monitoring data have been used. We focus on the empirical models here. Most of the identified studies for UFP were based on mobile or short-term monitoring campaigns. For BC models have also been developed based upon more prolonged sampling campaigns. Models based upon mobile monitoring campaigns often explain only a moderate amount of measured spatial variability, typically less than 50%. A problem with UFP models is its specificity, from models of other particle components or gaseous components from similar sources. Models for UFP are now available in a variety of typically urban study areas. Application in epidemiological studies will allow assessment of long-term exposure effects. BC models have been applied extensively in epidemiological studies.