Friday 18 July 1-2pm

A 400 year mega drought in the Murrumbidgee River catchment…and the future is?

R.J. Wasson, Charles Darwin University
T. Pietsch and J. Olley, CSIRO Land and Water

Summary

There were no large floods in the Murrumbidgee River between 1200 and 1600 AD.  Large floods returned between 1600 and 1950 AD and there have been none since.  The mega drought that ended in 1600 AD occurred during a prolonged period of El Niño – like conditions.  The mega drought also occurred in the Australian-Asian monsoon region, and is seen in a reconstruction of sea surface temperatures in the NIÑO-3 region of the Pacific.  The likely causes are changes in solar irradiance, volcanic dust, and heat transport in the ocean. 

The absence of large floods since 1950 AD and the presence of large floods in the Top End since ~1975 AD is consistent with current understanding of the impact of increasing Greenhouse gases.

Is the region of ENSO impact entering a new phase dominated by El Niño’s?

The Fenner School Seminar Series in 2008 is held in the Forestry Lecture Theatre
Forestry Building 48, Linneaus Way (comes off Daley Road), ANU (Acton) campus, ACT

The seminar will start at 13:00 and finish at 14:00