Tuesday, January 29, 2013

Tropical Cyclone Oswald

On 17th January, an area of low pressure developed over the the Gulf of Carpentaria several thousand kilometers to the north of us. The system quickly organized and strengthened into a tropical cyclone early on 21st January.
Although a relatively weak storm, Oswald produced torrential rain over much of Queensland causing extensive flooding, severe winds and even tornados.
In what is considered a strange set of circumstances the now intense low storm moved south down the east coast of Australia leaving chaos in its wake

                     Late last night it hit us with torrential rain and rather high, but not high as predicted, winds. We were warned of possible 100km/hr plus.
We have had nearly 150 mm of rain in 2 days. The dams and tanks are full and the creek is running again.
The surf is HUGE with 10m swells off the coast.
Needless to say the potential drought is over and, even better, the bush fires are out.

Monday, January 21, 2013

Grapevines / Heat Damage

A couple of days of 40C deg plus and some fierce drying winds have taken their toll on the grapevines.
When you take into consideration that the official temperatures are taken in the shade it's not hard to imagine what the exposed temperatures would be. Some estimates are 10-20 degrees higher.
Plants draw moisture up from the soil via their roots and expel it mainly through their leaves in what is known as transpiration.
When the rate of transpiration exceeds the rate of absorption the plant comes under stress.
The plant tries to compensate by closing the stomata in its leaves to prevent water loss but under extreme conditions of heat, air movement and low humidity this is not always possible.
This is when the leaves start to wilt or droop. If a plant reaches permanent wilting point (PWP) it will more than likely die.

The lack of moisture in the leaves makes them susceptible to burn. We noticed this happening with the grapevines very early in the heatwave as we have had very little rain and the soil moisture content is very low.
A couple of days later the leaf damage was more than obvious.
These damaged leaves will eventually die and fall.
A reduction in the number of leaves will affect the ability of the vine to ripen the fruit.

But the leaves weren't the only plant part affected. The fruit was also dehydrated by the heat with considerable raisining of the bunches.

All this will probably mean a considerable reduction in yield.
This is very disappointing as the vintage this year had been progressing well and harvest is or, maybe now, was only a few weeks away.
The worst affected is the Pinot Noir followed by the Tempranillo.
The Cabernet seems to have weathered the storm a little better as the vines are much older and the roots a lot deeper.
Only time will tell.

Friday, January 18, 2013

Another Scorcher

OK, these hot days can stop now.
We have had enough.
The temperature here reached 43.8 degC at 2pm.
The cool change didn't arrive until 5pm when the temperature dropped to 23 deg C within an hour .
We had headed down the beach in the morning for a swim but it was even too hot down there.
The poor garden is suffering too, the lawn turning brown and the grapevines are drooping.
Am sure we will have leaf and bunch burn on the outer rows.
In Sydney it reached just under 46 degC, which equaled the all time high record set in 1939.
Now for "our fire".

It became active again but thankfully the winds stayed down and its containment has been preserved on the southern side.
It has now burnt out 9100 ha.
Fires in the west of the state are still burning with 50 properties lost. At last count there were 90 with 30 uncontrolled. The largest has burnt out 52,000 ha.
And to finish off a great day, the gusty southerly wind obviously caused problems with the power supply. So we headed into town for dinner and have just now returned with the power finally restored.
So that's it for my whinge of the day.

Thursday, January 17, 2013

Brooman Revisited

Last year, around this time, the co driver's quilting group met at Brooman on the Clyde River for a family day.
This year we did the same but with a twist.
We all met at the Clyde River Berry Farm first.

It was a fairly bone jarring drive over the mountain range into the river valley along a route we have never taken before. This area is predominantly state forest and the dirt roads are used for transporting timber out and get pretty chewed up by the big trucks. And  since we haven't had much rain, it was very dusty as well.

The berry farm produces mainly blueberries but has a range of others as well including strawberries, raspberries and loganberries. It is a commercial farm which has PYO facilities for the tourists who flock to our area for the summer holidays.

The blueberries here are all low chill Florida high bush cultivars developed in the USA way back when but improved to the current standard by Ralph Sharpe of the University of Florida in the 1950s.
While doing my horticultural course I did my thesis on blueberry production and fully intended that the farm would be a commercial blueberry enterprise. Suffice to say it didn't happen for all sorts of economic and technical reasons.

                   We spent about an hour walking the rows, picking the fruit and having a sneaky taste now and again.
Then we headed for the weigh in. The cost was about half of what we pay in the supermarket.
It seemed we overdid it a bit with 2.5kg but we will freeze most of them for muffin and smoothie production.
And the Farm makes the best berry ice cream cones there too. Worth the trip just for one of those.
Then it was onto our friends' place on the river at Brooman for a picnic lunch and a bit of a fish.
It was a total reprise of last year ie. wonderful setting, warm sunny weather, great company, good food........and no fish, not even one bite!

Wednesday, January 09, 2013

A Scorching Day (with Final Bushfire Update)

A so called 'dome of heat' had formed over central Australia. This is not unusual at this time of year as it's summer but the temperatures were some of the highest on record with almost 50deg C (122deg F) being reached in some parts.
Due to a set of unusual weather patterns 'the dome' moved east and south.
The small island state of Tasmania which is normally the coolest in the country experienced extreme temperatures and the inevitable bushfires with more than 100 homes being lost in the south of the state.

Yesterday was our turn.
The bushfire warning was cranked up to "catastrophic" and we had messages delivered to us the night before via our landline and mobile phones to activate our bushfire survival plan.
We knew we were in for a bad day early in the morning. The temperature at 7am was already 32 deg C (90 deg F) and the wind was gusting strongly from the west.
By midday it was 40 deg C (104 deg F) and the winds were 70km/hr north westerly. The perfect storm.
We were aware a relatively small fire had started a few days ago to the north west of us and they had been working hard to contain it. Unfortunately the conditions turned it into a raging out of control inferno as it headed east towards the small beach side villages of the Sussex Inlet area.
This is about a 45 minute drive to the north of us.
We kept track of things through the excellent Rural Fire Brigade web site and were ready to 'hit the road' if necessary.

The main road north was soon cut and the residents who had not already left were sent to evacuation centers.
It was a pretty chaotic day up there.
Lots of pictures and stories from our local paper on this link.
As long as we didn't see smoke we knew we were ok.
At 6:30pm the long awaited southerly change came in. The temperature dropped 20 degrees in 15 minutes.
The fire up north is still burning today but conditions have eased. The Sussex Inlet villages are no longer in danger but the highway is still closed. This bush fire has a 44km perimeter and has burnt out an area of over 3,800 hectares.
There were over 140 bush fires burning in the state of New South Wales yesterday with around 20 threatening life and property. There is still a total state wide fire ban today.
This is summer in Australia and I don't think we have seen the last of the fires this season.
Update 10/01/13: The above fire is still not under control. Today 100 personnel, 8 helicopters and 27 fire trucks were involved in the fire fighting effort. So far 6500ha have been burnt but there has been limited property damage and no loss of life.
Conditions are expected to deteriorate over the next two days with higher temperatures predicted.
Update 12/01/13:  An earlier than expected southerly change today has helped firefighters get the upper hand in containing the blaze which has now burnt out more than 8400 hectares in the Jerrawangala area.
Around 175 fire fighters, with 31 tankers, are still working to contain the blaze over the 100km perimeter.
With them are 7 aircraft and about 10 heavy machinery units who will be working to strengthen containment lines throughout the day.
The really good news for fire crews was containment lines had held over night and the fire hadn't crossed through a former military range in the rugged and mostly inaccessible north west area which is scattered with unexploded bombs.The containment lines on the eastern side of the fire, near the Princes Highway, were holding and the threat to communities in and around Sussex Inlet had eased.
The cooler conditions expected to continue tomorrow and Monday.

Update 13/01/13: Much cooler weather (low 20s) with southerly winds bringing in the high humidity and even a suggestion of light showers. Can imagine the firefighters in our area are happier. "Our fire" is still considered out of control with the western front now in inaccessible country and being water bombed by aircraft. Eastern front which has been our main worry is contained. The cooler weather is expected to last a few more days then heating up again by late next week.
However a series of lightning strikes in the north of New South Wales have sparked 45 new bush fires.
Across the state 130 fires are now burning, 30 of which are not contained. Temperatures in that region have been in the 40s.
Moomba in the far northeast of South Australia yesterday recorded a maximum temperature of 49.6 degrees, which makes it the highest temperature recorded in Australia in 15 years.

Update 15/01/13: It appears that the threat from the fire has now abated. We have had some rain and the southerly wind stream, apart from bringing in much needed humidity, has pushed the fire to the north west. The eastern perimeter which was our main worry is contained. But the fire is not out and more hot weather and the wrong wind could change this situation.
Meanwhile out west of the state the fire situation is dire. Lots of property and stock losses.