changing climate: compost effect crisis, page-9

effect of 1metre sea level rise on wa coast http://www.abc.net.au/perth/stories/s1729593.htm

What would Mandurah look like if the sea level rose one metre?

Friday, 1 September 2006

Reporter: Sarah Knight
photo of Mandurah

The coastline at Mandurah if there is a 1m rise in sea level. Image developed by David Giffard with data provided by Geoscience Australia.

photo of Rockingham

The coastline at Rockingham if there is a 1m rise in sea level. Image developed by David Giffard with data provided by Geoscience Australia.

photo of Warnboro

The coastline at Warnboro if there is a 1m rise in sea level. Image developed by David Giffard with data provided by Geoscience Australia.


Global climate change is now recognised by the majority of scientists as being an - unfortunate - fact of life. Or rather life as we now live it. An increase in global temperature will result in an increase in sea level. These images, developed by David Giffard with data provided by Geoscience Australia, show the impact of a one metre rise in sea level on some of our coastal communities.

According to Dr Brian Ryan from CSIRO Marine and Atmospheric Research a one metre sea rise is more likely to happen than the seven metre rise predicted if the Greenland Ice Sheet melted.

The Ice Sheet will melt if we have a sustained global temperature rise of 3 degrees above 1990 levels. This will shift Perth's coastline inland by 700 metres. We are already 0.8 degrees above those 1990 levels. [Thirty/Ten July 2006 - Magazine of the Western Australian Sustainable Energy Association Inc]

Dr Ryan says: "IPCC (Intergovernmental Panel on Climate Change) estimates of global sea level rise by the end of this century could be approaching one metre. However, these calculations do not take account of the melting of the Greenland Ice sheet.

"If increasing sea level rise is accompanied by higher intensity storms them storm surges also become an issue. In the recent climate change observed in the SWWA thee has been no evidence of increases in the intensity of storms."

Dr Ray Wills, Adjunct Senior Research Fellow, School of Earth and Geographical Sciences at The University of Western Australia, says "sea levels have already risen in Western Australia 18.5 cm in the last 100 years (as they have globally) with predictions that this rise will at a minimum double (38 cm forecast), and very probably triple (more than 48 cm), in the next ninety years (by 2100). The potential for a one metre sea level rise by the end of this century is not an extreme estimate, but is well within the bounds of scientifically-based predictions. With those sorts of rises, much of the low lying areas around areas like Perth, Fremantle, Mandurah and Busselton/Margaret River are under threat, and coastal freshwater swamps will go saline."

He says "submerged fringing reefs currently a barrier protecting parts of Perth's coastline will be further submerged allowing bigger waves to previously sheltered beaches. In other places in WA, bleaching of coral from higher ocean temperatures will kill parts of the Ningaloo Reef just as it will the Great Barrier Reef."

Further, Dr Wills goes onto say that "almost all scientific opinion on climate change, reported by UN Intergovernmental Panel on Climate Change and endorsed by national science academies of G8 nations as well as national science academies of Australia and of Brazil, China and India, concludes that global warming is attributable to human activities. Indeed, most multinational companies acknowledge this - visit the websites of any of Australia's biggest companies and there will be discussion of the threat of global warming. (And some industries are strongly united in this view - see the Australian Business Roundtable on Climate Change." (link below)

"Despite all the evidence," Dr Wills says, "much of the media behaves as though the jury is still out. Further, the actions (and inactions) of governments at all levels do not match the extraordinary high level of risk and uncertainty that will continue to grow if we fail to act now."

While it's unlikely that the sea level will rise seven metres in our lifetimes but what would our coastline look like if it did? Find out here