Australian Institute of Physics

South Australian Branch

Free Public Lecture

at 7:30 pm, Tuesday September 30th 1997

in the FLENTJE Lecture Theatre,

Plaza Building, The University of Adelaide

(go down the steps at the NorthEast corner of Hughes Plaza,

or enter from the Horace Lamb building)

"Detecting a Human Influence on Global Climate"

by Professor David Karoly

CRC for Southern Hemisphere Meteorology

Monash University, Clayton VIC 3168

The recent intergovernmental assessment of climate change

concluded that "climate has changed over the past century" and that

"the balance of evidence suggests a discernible human influence on

climate". A brief review will be presented of some of this evidence

and the methods which have been used to detect significant changes

in climate and to attribute these changes to human influences.

Major human influences on global climate are due not only to

increasing greenhouse gases in the atmosphere, but also to

increasing amounts of tropospheric aerosols and to decreasing

concentrations of ozone in the stratosphere. Climate model

simulations forced by changes in these three factors show good

agreement with observed changes in the thermal structure of the

atmosphere over the last three decades. This agreement is unlikely

to have occurred by chance through natural climate variability.




Prof David J Karoly

BSc Hons (Maths), Monash 1976

PhD (Meteorology), Reading, 1980

Professor Karoly is Director of the Cooperative Research Centre for

Southern Hemisphere Meteorology and a Professorial Fellow at Monash

University, in Melbourne, Australia. He is active in research into

the dynamics of the large scale circulation of the atmosphere and

its variability on time scales from days to decades. Specific

research interests include greenhouse climate change, stratospheric

ozone depletion and interannual climate variations due to the El

Nino-Southern Oscillation. He is a member of a number of national

and international committees, including the Scientific Steering

Group of the WCRP project "Stratospheric Processes and their Role

in Climate" (SPARC), and the Australian Academy of Science's

National Committee for Climate and Global Change. He was a

contributor to the recent scientific assessment of climate change

prepared by the Intergovernmental Panel on Climate Change. In 1993,

Professor Karoly received the Meisinger Award from the American

Meteorological Society, with citation "for contributions to the

understanding of the role of Rossby wave propagation in atmospheric

teleconnections and to greenhouse climate change research".

The Meteorology CRC was established in 1993 and is a joint venture

between Monash University, the Bureau of Meteorology, CSIRO

Divisions of Atmospheric Research and of Telecommunications and

Industrial Physics, and Silicon Graphics Pty. Ltd. The CRC is based

at Monash University on the Clayton campus, with a budget of more

than $4M per annum in cash and in-kind contributions. It has three

research programs, in Stratospheric Ozone, in Global Transport

Modelling and in Southern Hemisphere Climate Dynamics, together

with an Education program and a Technology Transfer and

Communication program.