Another El Nino looking more likely
Staff, Queensland Border Mail
If you’re partial to gambling, put your money on another drought as least as severe as 1982-83. That’s the advice of long-range weather forecaster John Moore who gives the Border and North East a 70 per cent chance of experiencing a summer of drought and high temperatures. His prediction follows one of the region’s driest winters and the threatening re-emergence of the El Nino phenomenon.
“The Southern Oscillation Index was positive in April and now it’s gone very negative, the Indian Ocean gives us upper air moisture and that hasn’t been happening and we’ve not been getting moisture from the east coast – these three factors usually result in dry weather,” Mr Moore said.
(1 Sept 2006)
The papers same day editorial: Hard decisions are needed now (more dams?).
Contributor SP writes: The Murray Darling Basin is the major river system in Australia supporting a large number of irrigation fed agroindustries (details at www.mdbc.gov.au).
It is the begining of the irrigation season and the Hume Reservoir is only at 17% of capacity [http://www.mdbc.gov.au/subs/river-info/weekly-report/live-wreport/current_wr.pdf]. To maintain flows the larger Dartmouth Dam upstream will have to be drawn down.
This report [http://www.mdbc.gov.au/__data/page/20/July2006-Drought-update.pdf] indicates that the current conditions have led to record low 5 year inflows and that it has been a decade since many wetlands and floodplains downstream recieved benificial flows.
Ozone-layer fix adds to global warming
John Heilprin, Arizona Daily Star/Associated Press
WASHINGTON — Cool your home and warm the planet.
When more than two dozen countries undertook in 1989 to fix the ozone hole over Antarctica, they began replacing chlorofluorocarbons in refrigerators, air conditioners and hair spray. But they had little idea that using other gases that contain chlorine or fluorine instead also would contribute greatly to global warming.
CFCs destroy ozone, the atmospheric layer that helps to protect Earth against the sun’s most harmful rays. The chemicals also trap the Earth’s heat, contributing to a rise in average surface temperatures. In theory, the ban should have helped both problems. But the countries that first signed the Montreal Protocol 17 years ago failed to recognize that CFC users would seek out the cheapest available alternative.
The chemicals that replaced CFCs are better for the ozone layer, but they do little to help global warming. These chemicals, too, act as a reflective layer in the atmosphere that traps heat like a greenhouse.
(21 Aug 2006)
Oceanography: Sick seas
Jacqueline Ruttimann, Nature
The rising level of carbon dioxide in the atmosphere is making the world’s oceans more acidic. Jacqueline Ruttimann reports on the potentially catastrophic effect this could have on marine creatures. ..
In 1800, the carbon dioxide in the atmosphere was 280 parts per million, and the oceans’ pH averaged 8.16. Today there are 380 parts per million of carbon dioxide in the atmosphere, and the pH of the oceans is on average 8.05. Estimates suggest the pH could drop to 7.9 by the end of the century. The drop from 8.16 to 7.9, says Kleypas, “doesn’t sound like much, but it’s a lot.” Each one-step change on the pH scale indicates a tenfold change in acidity. ..
Because carbonate is more soluble in high pressures and cold water, increased acidity has a greater effect at depth. But Orr’s studies suggest that aragonite will be unstable at all depths throughout the Southern Ocean by 2100. Once the corals go, so too may other species that rely on them for resources such as shelter. ..
(31 Aug 2006)
Scientists ‘surprised’ on climate change
Evan Schwarten, News.com/AAP
AUSTRALIA’S rapid climate change had caught scientists by surprise, a leading water expert said today. Professor Peter Cullen, from the National Water Commission, said experts had expected the changes, which have left much of the country suffering drought conditions, but thought they would take much longer to take effect.
“I don’t think any of us expected the climate change we have experienced over the last five years. I was expecting climate change but I was expecting it to take 30 years,” he said. Prof Cullen said Australia was drying out quickly and with water restrictions already in place in many areas, governments needed to consider all available options, such as recycling and desalination, to prevent an impending water crisis. ..
Prof Cullen was speaking at Brisbane’s International River Symposium alongside the World Wildlife Fund’s Dr Stuart Blanch, who criticised the Queensland governments dam plans: “What’s the point in building big dams if they remain half full? It’s much smarter to move to recycling.” ..
(4 Sept 2006)
