Science Source

On the Measurement of Heat Waves

Employs a set of three heat wave definitions, derived from surveying heat-related indices in the climate science literature
Includes the following three definitions for heat waves: three or more consecutive days above one of the following: the 90th percentile for maximum temperature, the 90th percentile for minimum temperature, and positive extreme heat factor (EHF) conditions
Studies each index using a multi-aspect framework measuring heat wave number, duration, participating days, and the peak and mean magnitudes
Presents observed climatologies and trends for the Australian continent for two time periods (1951–2008 and 1971–2008)
Finds that trends in all aspects and definitions are smaller in magnitude but more significant for 1951–2008 than for 1971–2008
Finds that considerable similarities exist in trends of the yearly number of days participating in a heat wave and yearly heat wave frequency, suggesting that the number of available heat wave days drives the number of events
Finds that larger trends in the hottest part of a heat wave suggest that heat wave intensity is increasing faster than the mean magnitude