Doctoral Dissertation Research: Examination of Local-Scale Spatial Variability of Heat Fluxes Across an Urban Area: Integration of Measurements, Remote Sensing, and Modeling

Indiana University, Bloomington IN

Investigators

Abstract

Urban energy consumption and land-surface modification create distinct patterns of urban climates by altering the exchange of energy, mass and momentum with the atmosphere. These processes are linked to phenomena such as the urban heat island, the transport and dispersion of pollutants and are fundamental to understanding urban impacts on weather and climate. This doctoral dissertation research will investigate the transfer of energy between the urban landscape and the atmosphere through a combination of meteorological measurements, remote sensing and numerical modeling. This combination of methods generates accurate measurement of exchanges over the local-scale (~1 km, e.g. neighborhoods) and extends them to the scale of a city. Previous studies, conducted mostly in North America, were limited by short-duration campaigns or lacked direct measurements by which to evaluate models. The study will be conducted in Lodz, Poland; selected because it experiences a different seasonal climatic regime to those sites already studied, large amounts of anthropogenic heat are released in the winter-time, and the building style (density and morphology) of the city is distinct from North American cities but typical of many cities in central Europe. This research will enhance existing long-term measurements in Lodz and address the lack of understanding of within urban variability by adding direct measurements in areas with differing building densities and land-uses. These sets of measurements will provide the basis for calibrating remote sensing and numerical models of the exchange processes. The patterns and magnitudes of fluxes predicted by the two approaches can be interpreted in the context of emerging understanding of heat exchange across the urban landscape given that direct observations on this large an extent are not possible. Urban areas, although small in terms of total land surface area, are growing and contain an increasingly large share of the world's population. Thus urban-atmosphere interactions disproportionately impact humans with implications for human health, safety and comfort. Moreover, urban effects extend beyond the boundaries of cities, with implications for regional and larger-scale atmospheric conditions and climates. With increases in computing capacity, numerical weather forecasting, air pollution and long-term climate models now run with greater spatial resolution and can explicitly incorporate urban areas. This research will contribute directly to the development of such models, by producing a methodology by which to study local urban impacts as well as providing data against which to evaluate predictions. As a Doctoral Dissertation Research Improvement award, this award also will provide support to enable a promising student to establish a strong independent research career.