The duration and severity of drought over eastern Australia simulated by a coupled ocean–atmosphere GCM with a transient increase in CO2

The combined effects of precipitation and temperature simulated by a coupled ocean–atmosphere General Circulation Model that showed an El Niño-like pattern with a transient increase in CO2, was examined for its effects on drought over eastern Australia. The Palmer Drought Severity Index (PDSI) was applied to determine the duration and severity of drought over a 30-year period due to decreased precipitation over the region. Application of the PDSI, using monthly mean temperature and total monthly precipitation to the final 30 years of the transient CO2 simulation revealed more prolonged and more intense periods of drought under enhanced greenhouse conditions when compared to a similar time span of the present-day simulation.