The Spatial Variability of Heat-related Mortality in Massachusetts

Applied Geography

Applied Geography, Volume 33, April 2012

David Hattis, Yelena Ogneva-Himmelberger, and Samuel Ratick

“Highlights

  • We assess the spatial distribution of heat-related mortality in Massachusetts.
  • Areas with high elderly and African–American populations have elevated mortality on hot days.
  • Urban areas do not exhibit significantly higher heat-related mortality than rural areas.

” This study assesses heat-related mortality in Massachusetts during the months of May through September from 1990 to 2008. Daily maximum apparent temperature was interpolated across space via kriging, and aggregated to 29 municipality groups (MGs), a spatial unit composed of municipalities that was designed to have minimal variation in population. Death certificate data were analyzed to determine the spatial distribution of excess mortality on days that exceeded the 85th, 90th, and 95th percentiles of apparent temperature. We find that the average statewide mortality anomalies were 5.11, 6.26, and 7.26 deaths on days exceeding the 85th, 90th, and 95th percentiles of apparent temperature respectively. A linear stepwise regression showed that percent African–American population and percent elderly population (those above the age of 65) were positively associated with an MG’s mortality anomaly on days exceeding the 85th percentile of apparent temperature (p < 0.05). In spite of the urban heat island effect, our measure of urbanization was not associated with higher rates of heat-related mortality.”

Recent Progress in the ANUDEM Elevevation Gridding Procedure

Geomorphometry 2011Geomorphometry 2011, 07-09 September 2011, Esri, Redlands, California

Michael Hutchinson

“Topography plays a fundamental role in modulating land surface and atmospheric processes across a wide range of spatial scales (Hutchinson 2008). Thus digital elevation models (DEMs) have played a key role in supporting mesoscale representations of surface climate as well as in supporting finer scale representations of surface hydrology and catchment processes. The ANUDEM locally adaptive elevation gridding procedure (Hutchinson 1989, 2007) is commonly used to calculate these elevation models in regular grid form. Key features of the method include its computational efficiency, allowing it to be applied to very large data sets, and a range of locally adaptive features, including a drainage enforcement algorithm that attempts to maintain connected drainage structure in the interpolated DEM, and algorithms to incorporate data streamlines, lakes and cliffs. This paper describes current progress in the ANUDEM procedure to better represent lakes and to effectively process noisy, high resolution elevation data. Such data are becoming increasingly common. The underlying multi-grid interpolation procedure remains effective in effectively representing lakes and cliffs and in stably interpolating high resolution elevation data. Correlated errors in source elevation data can also be specifically accommodated. The multi-grid procedure also plays a crucial role in enabling the application of drainage enforcement and in initializing heights on data streamlines. This can prevent corruption of stream heights by noisy elevation values and improve the overall representation of drainage structure in the presence of dense noisy elevation source data.”

All presentation materials and reviewed papers from Geomorphometry 2011 are available at http://geomorphometry.org/content/geomorphometry-2011-programme.