Unpredictable rainfall is normal in Australia but these days it is all due to "climate change"
If the rain is not falling in Sydney's catchments and throughout southern Australia, where has it gone? The answer, says the acting head of the Bureau of Meteorology's National Climate Centre, David Jones, is north-west and Central Australia, where residents are finding climate change may have a wetter flipside.
Most dramatic is the desert outpost of Giles, which sits on the edge of the Tanami Desert near the junction of South Australia, Western Australian and the Northern Territory. In 50 years the remote weather station, home to five people, has seen its rainfall double - from a yearly average of about 150 millimetres to around 300.
If current trends continue, ecological changes will begin to follow - greener for the desert and the Kimberley, but browner for southern Australia. Because Giles is one of the driest spots in the continent, a doubling of rainfall has not yet had a visible impact, says the officer in charge of the weather station there, Michael McIlvenny. But Dr Peter Kendrick, Pilbara-based regional ecologist with the West Australian Department of Environment and Conservation, said doubling rainfall has a "huge impact" in such an ecosystem, given that desert fauna and flora are tuned to respond rapidly to episodic rainfall. Dr Jones says he already believes the extra rainfall in some other less arid areas has given agriculture and grazing a valuable buffer against degradation.
But in southern Australia, the colour of climate change seems to be brown. Dr Michael Raupach, a scientist with the CSIRO Division of Marine and Atmospheric Research, and chairman of the Global Carbon Project, has recently made some frightening observations from satellite photography. He and his team have discovered large swathes of the continent are becoming visibly less green. "Depending on the area, we are finding parts of the continent that are more than 50 per cent less green," he said. "This means a browning of the continent. The trend started in the late 1990s and since then has been going on in a ratchet fashion, with jumps in browning occurring in drought years."
What makes this finding so alarming is that if the drought does not ease then the logical conclusion of the current trend is a massive death of vegetation, huge bushfires and the release of vast volumes of carbon, further feeding climate change. Normally, Dr Raupach said, forests have the chance to recover through flooding rains between droughts, but the low-rainfall conditions of the past decade have been relentless. While sporadic recovery of greenness occurred in places, nowhere has vegetation climbed back to what it normally would be between droughts. Worst affected seem to be south-west Western Australia and almost the entire Murray-Darling Basin, ecosystems, already fragile because of land degradation. "It's almost literally true that it keeps me awake at night," Dr Raupach said.
The weather bureau's Dr Jones says "superficially, the rainfall shift to the north-west of the continent doesn't make a lot of sense". This is because theoretically the entire nation has been in the grip of El Nino for much of the last decade. Perhaps the huge release of aerosols into the atmosphere by Asian nations could be a factor in the increased rain, he said. One thing that is certain is that the Australian climate has shifted dramatically in the past half century. In a vast band of the continent between the Nullarbor coast and the Kimberley there has been an average annual increase in rainfall of between 100 and 200 millimetres. "Around Broome and Wyndham, rainfall has increased by 300 millimetres - particularly in summer and autumn," Dr Jones said.
On the other hand, Sydney's annual rainfall has decreased by between 100 and 200 millimetres a year and in Mackay by as much as 300 millimetres a year compared to the 1950s. Weather systems known as north-west cloud bands used to travel across the continent from monsoonal troughs in the Kimberley, bringing the kind of rain to southern Australia which filled dams and caused floods. "In the last few years to a decade these north-west cloud bands have almost disappeared. The linkage to the tropics has broken down," Dr Jones said. "Since 1950, since global temperatures have increased along with aerosols and ozone, all of a sudden we have seen rainfall trends that are very distinct. "One would be naive to put these trends down to natural variations. They're very large and a number are consistent with what we see from climate change computer models."
The drying of southern Australia has attracted the most attention until now, he said. "What we are seeing in the rest of Australia is just as dramatic, it's just that it's positive. People don't seem to notice climate change when it's beneficial to humans." Dr Kendrick said with greater rainfall, vegetation would increase in arid areas. There would be changes in fauna. The desert mouse had extended its range from the central deserts to the west Pilbara, and camel numbers were increasing.
Source
THAT PESKY OZONE HOLE STILL WON'T DO WHAT THE GREENIES TELL IT!
Still no visible effect of the Greenie ban on our best refrigerants
The hole in the ozone layer over the southern hemisphere is the largest ever, covering an area more than three times the size of Australia. During the last nine days of September, the hole in the ozone layer covered, on average, nearly 17.5 million sq km. The expansion to a size greater than the surface area of North America has been observed in recent weeks by American and Australian scientists. "We now have the largest ozone hole on record," said Craig Long of the US National Oceanic and Atmospheric Administration (NOAA). The ozone layer girdles the Earth in the upper atmosphere, or stratosphere. It protects plants, animals and people by blocking harmful ultraviolet rays from the sun.
Ozone depletion is caused by the effects of stratospheric chlorine and bromine. The gasses are released in summer when sunlight acts on artificial compounds like chlorofluorocarbons once used as coolants and fire retardants. The record-breaking hole was announced yesterday by the US space agency, NASA, and NOAA. Scientists at the CSIRO identified the hole last week, said atmospheric scientist Paul Fraser. "We were looking at data on the NASA site and noticed the hole looked likely to be the biggest ever," Dr Fraser said.
The data was recorded by the Ozone Monitoring Instrument aboard NASA's Aura satellite. The instrument detected record low levels of ozone over the East Antarctic ice sheet. Balloon-borne instruments operated by NOAA made further measurements directly over the South Pole. Ozone levels had plunged from 300 Doppler Units (DU) -- a measure of ozone between 13 and 20km above Earth -- to 93DU. "These numbers mean the ozone is virtually gone in this layer of the atmosphere," said David Hofmann, director of NOAA's Global Monitoring Division. "The depleted layer has an unusual vertical extent this year, so it appears that the 2006 ozone hole will go down as a record-setter."
While the size of the hole is alarming, it does not mean that increased amounts of ozone-depleting chemicals are reaching the atmosphere, said Paul Lehmann with the Bureau of Meteorology Research Centre in Melbourne. "There is mounting evidence that the ozone is slowly recovering," he said. "The (yearly) size of the hole is due to the effect of atmospheric influences like wind and temperature." Dr Fraser noted that these conditions differed from year to year, effectively "masking" the decline in ozone-depleting substances and the increase in protective ozone. "There are less ozone-depleting chemicals but they are more effective (when it's cold)," Dr Fraser said. "This is the coldest year ever." Also, chlorine and bromine remain in the stratosphere for about 50 years.
Signatories to the 1975 Montreal Protocol and its amendments, including Australia, agreed to phase out ozone-depleting substances. Its estimated [i.e. theorized] levels of the destructive gasses peaked above Antarctica in 2001 and are now declining.
Source
GROWING GLACIERS FAIL TO DENT THE GLOBAL WARMERS
Global warming has become a classic unfalsifiable hypothesis. They can "explain" anything. Evidence shows anything you want
Some glaciers in Pakistan's Upper Indus River Basin appear to be growing, and a new study suggests that global warming is the cause. The glacial growth bucks a global trend of shrinking ice fields and may shed light on the regionally varying effects of Earth's changing climate.
Meteorological data compiled over the past century show that winter temperatures have been rising in parts of the Western Himalaya, Karakoram, and Hindu Kush mountain ranges (map of Pakistan). But the region's winter snowfall, which feeds the glaciers, has been increasing. And average summer temperatures, which melt snow and glaciers, have been dropping. "One of the surprising results we found was a downward trend in summer temperatures," [Hey! Where's that global warming?]said David Archer, study co-author and a hydrologist at Newcastle University in the United Kingdom. "That seems to be at odds with what people would expect, given the news about glaciers melting in the Eastern Himalaya."
The combination of reduced summer melt and more winter snowfall could account for glacial growth, according to work to be published by Archer and colleagues in an upcoming issue of the American Meteorological Society's Journal of Climate. The new study compiled thousands of pages of climatic data that were collected at weather stations during the past century.
The records even include 19th-century documents taken from British archives that predate the creation of modern Pakistan in 1947.....
The data also reveal another climatic oddity-a change in the basin's diurnal temperature range, or the span between daytime high and nighttime low temperatures for a given day. "There's a large increase in the diurnal temperature range observed in all seasons and in all the annual data sets," Archer said. "In most parts of the world there's been a decrease in diurnal temperature change, and this is what's being predicted by global climate-change models." ....
All together, the area's regional variations are at odds with most glaciated regions worldwide, including the Eastern Himalaya, where glaciers have been shrinking significantly....
It may take many years to understand climate change's lasting effects on Pakistan's glaciers. But Archer hopes for much more immediate payoff from the recently published climate data. "We're not entirely sure what long-term climate change trends will do," he said. "But in the meantime, [water forecasting] is a really important, immediate, practical issue."
More here
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Many people would like to be kind to others so Leftists exploit that with their nonsense about equality. Most people want a clean, green environment so Greenies exploit that by inventing all sorts of far-fetched threats to the environment. But for both, the real motive is to promote themselves as wiser and better than everyone else, truth regardless.
Global warming has taken the place of Communism as an absurdity that "liberals" will defend to the death regardless of the evidence showing its folly. Evidence never has mattered to real Leftists
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Jim Hansen and his twin
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