Maleny Weather

Listening to the news yesterday, you might have been forgiven for thinking it was April 1, not March 30th

The BBC soberly reported that scientists were considering using wind-driven ships to spray salt into the air to make clouds whiter so they could reflect more solar energy and help reduce global warming.

Stranger still, it turns out this is just one of the ingenious ideas discussed in a special edition of the Royal Society’s journal devoted entirely to the pros and cons of geo-engineering, large-scale interventions to help modify the Earth’s climate.

Others include blocking sunlight by floating mirrors in space, using rockets to spray sulphur into the upper atmosphere, and seeding the oceans with iron to trigger plankton blooms that would draw carbon from the water before locking it away on the sea bed as the plankton died and sank to the bottom.

The cloud-seeding idea is explored in a section called “Sea-going hardware for the cloud albedo method of reversing global warming”.

It explains: “Wind-driven spray vessels will sail back and forth perpendicular to the local prevailing wind and release micron-sized drops of seawater into the turbulent boundary layer beneath marine stratocumulus clouds. The combination of wind and vessel movements will treat a large area of sky.

“When residues left after drop evaporation reach cloud level they will provide many new cloud condensation nuclei giving more but smaller drops and so will increase the cloud albedo to reflect solar energy back out to space.”

But before you think it’s ok to leave all the lights on and take your 4 x 4 out for a spin, the Royal Society makes it clear such schemes would only tackle the symptoms, not solve the problem.

“None of these technologies will provide a ‘get out of jail free card’,” said Martin Rees, President of the Royal Society. “They must not divert attention away from international efforts to reduce emissions of greenhouse gases.”

Flash floods happen suddenly (hence the name), forming in less than six hours. This sets them apart from “regular” floods, such as river floods, which can often be predicted days in advance. They are caused when a heavy rain falls over low-lying areas, especially when the soil is already saturated. They happen when rainfall intensity and duration match up, in a very bad way.

More than half the fatalities happen when people try to cross flooded intersections in their cars. This is because people are generally not very good at judging the depth and danger of flooded streets. (They can’t actually see the roadway surface, which might be a big deep hole.) While two feet of water doesn’t seem like much at all, especially if you are safely inside a big, heavy car, it is enough to carry you and the car away. (Another fact we tend to forget: cars are buoyant.)

According to the NOAA , “Water weighs 62.4 lbs. per cubic foot [1,010 kg per cubic meter] and typically flows downstream at 6 to 12 miles an hour [10 to 20 kph]. When a vehicle stalls in the water, the water’s momentum is transferred to the car. For each foot the water rises, 500 lbs. [226 kg] of lateral force are applied to the car. But the biggest factor is buoyancy. For each foot the water rises up the side of the car, the car displaces 1,500 lbs. of water. [For each meter the water rise up the side of the car, the car displaces 2,040 kgs of water.] In effect, the car weighs 1,500 lbs. [2,040 kg] less for each foot [meter] the water rises.”

Do not be tempted to drive across a flooded roadway.(”Don’t drown; turn around.”) If you find your vehicle stalled in a flooded road way, leave it and seek higher ground. (”Better wet than dead.”)

This video on YouTube of a flash flood in Merriwa, NSW, shows just how quickly a flash flood can occur.

A wetter than normal season is favoured for south-east Queensland, with temperatures cooler than normal according to the Bureau of Meteorology

At least 35 people have been killed and hundreds of houses are underwater after a dam burst near the Indonesian capital Jakarta. An emergency services spokesman says the dam on the south-western outskirts of the capital burst in the early hours of the morning after heavy rain

Over the past week there was little change in the weather on the Range. A high of 1025hPa in the Tasman Sea and a deep low in the Coral Sea, that for a short while became TC “Jaspin”, brought southerly maritime trade winds on to our shores. Days were dry and humid with temperatures in the mid twenties. It was not until Saturday that winds strengthened from an interaction between the high in the Tasman Sea and the ex-TC “Jaspin”. Sunshine and showers, heavy at times, were the order of the day. Total week’s rainfall came to 6.8 mm, bringing the month’s total to-date to 209.8 mm. The week’s evaporation was 11.6 mm and Bright Sunshine shone for 50.8 hours.

It was a very wet and muddy March in 1898 when 1289 mm of rain was recorded at Maleny and life must have been very difficult for the early settlers and navvies constructing the Landsborough section of the railway line from Brisbane to Cairns. The first train arrived at Landsborough Station in 1890 at a time when the next section to Yandina was under construction. Two tunnels were constructed, one between Landsborough and Mooloolah and the other between Mooloolah and Eudlo.  Heavy rainfall made track-laying difficult.  I thoroughly recommend the walk Kay and I did when we followed the old disused rail track from Mooloolah into the Dularcha National Park. A short 10/15 minute walk and you come to the Dularcha tunnel. There is no light at the end of the tunnel because of a slight bend. Stand silently in the middle of the tunnel and you can almost hear the steam locomotive puffing its way up the slight incline. In fact, it was this incline that limited the number of train carriages and resulted in a second tunnel being built during the depression of 1931, a couple of metres lower and with a less steep approach.

As we delve into past events covering the autumn month of March one marvels at just what the early settlers on the Range had to put up with when logging an area in deep mud. Before roads were built the Red Cedar trees were felled and hauled to the nearest ‘chute’. If you go along Maleny’s Mountain View Road to McCarthy’s Chute, ponder awhile to imagine how the logs were brought through the rain forest by bullock teams and rolled over the steep escarpment to the sawpit below. There they were either sawn into flitches or rafted down Coochin Creek to Bribie Passage. Sailing ships would then tow the rafts to Brisbane.

An old English traditional annual event called The Flitches of Dunmow in Essex where a side of a hog salted and cured and given yearly to any couple proving conjugal harmony for a year and a day

A high over the Tasman Sea will continue to maintain moderate to fresh South-east trade winds on to the Ranges for the rest of the week. A few isolated showers can be expected but the weather will be mostly fine for our region

The week started with a thunderstorm on Monday evening with some moderate falls of rain filling rain gauges. It’s been a week of sunshine and showers with temperatures in the mid-twenties. This month’s Relative Humidity has been the highest recorded in March for several years.  Bright Sunshine for the week was 36 hours.  A low pressure system in the Coral Sea was expected to turn into a tropical cyclone, but an upper level atmospheric environment was not favourable for this to happen and instead moved the low farther away from the coast into cooler waters.

A deal has been signed today to create two new supercomputers in Australia to forecast weather and track climate change.

The Australian National University and the Bureau of Meteorology will build the new computers at the ANU campus in Canberra and in Melbourne.

 The head of ANU Supercomputing Facility, Ben Evans, says the new ANU system is expected to be operational by the end of the year, and would be among the world’s top 30 high performance computing systems.

Acting Director of the Bureau of Meteorology Dr Neville Smith says it will give researchers the extra processing power needed to do more demanding climate forecasts.  “Together the new supercomputers will provide the computer power needed to develop the Australian Community Climate and Earth System Simulator – a new project to tie together weather forecasting as well as climate and ocean forecasts,” he said.

The new supercomputers are expected to be operational later this year.

With every country seeking to satisfy its water needs from limited water resources, some foresee a future filled with conflict. But history shows that cooperation, not conflict, is the most common response to trans-boundary water management issues. “Shared water, shared opportunities” is the theme for World Water Day 2009 on 22^nd March

Whether we live upstream or downstream, we are all in the same boat.