Monday, 11 December 2017

More garden flowers

Some of these came out in the last couple of days.  Others are ones I have just decided to add.

We have a good collection of geraniums on the deck.  These are a rather orange set.
 some white lilies have joined the orange and maroon samples.
 A close up of the Acanthus: they actually look to be getting towards the end of their flowering time.
 Some red Penstemons...
 ... and white/pink ones.
 Finally some red Salvias.

Sunday, 10 December 2017

Some larger flowers in the garden.

Having finally got some decent rain (over 60mm in each of the last three months) some of the larger flowers in the garden are happening.  So are the weeds, but this is supposed to be a positive post!

Here are a few photos, beginning with a very large Acanthus, which was totally burnt in the fire, but has come back magnificently..
The same comments apply to the Red-hot pokers (Kniphofia sp).  Only one plant is currently flowering - somewhat early - but they are looking very vigorous in their growth.  I expect that part of the garden to become honeyeater heaven in the near future.
 Two colours of Oriental Lily are in flower.  This deep red one is rather lonely  ....
 ... but the orange ones are profuse.
 This is a low growing plant donated to us by the bushfire recovery program.  Its a Rehmannia.

Friday, 8 December 2017

Some longer term trends

I have been asked if I have fitted any trend lines to the data series from 1993.  At that time the answer was "No", but that was then and this is now.

There are many possible data items that could be used and - even using EXCEL - many trendlines that could be fitted.  To kick things off I have shown below:
  • Data series for annual average minimum and maximum temperatures
  • A data series for total annual rainfall;
  • With a 4th order polynomial trend fitted. I find that order tends to give a fairly high value of r2, without butchering the degrees of freedom too badly.

The values of  r2 for those series look reasonable (I don't have measures of significance available).
The value for r2 is quite low, suggesting no trend in these data.

The data comes from two sites in Carwoola which give pretty consistent readings, so I don't think the changes of site in 2014 (for temperature) or 2007 (for rainfall) affected matters greatly. 

Following on from comments on the initial publication of this post a question was asked about the cool values for 1993.  One way of addressing this is to look at BoM observations for the (now closed) site Canberra Airport Comparison NSW (Station Number 070014) which has data from 1949 to 2010.  I have charted temperature data for that site and the Carwoola records for the period 1993 to 2010.  Note that the data for Carwoola for the period is all from a single site (not on my property so I can't comment on detail).

In both sets of data the correlation coefficient between the series is ~0.70 suggesting the overall pattern is similar. 

As Carwoola is about 200m higher than the Canberra Airport I'm not surprised that the minimum temperatures are lower.  As the Carwoola data is not on my property I can't comment on the reason for the rise in minimum temperatures between 1997 and 1999 but the observer at that time provided data from a weather station.  He has also commented in the past that minima differ across the property with low areas collecting cold air: I suspect growth of vegetation in some way changed airflow over the period.

I only have measured annual average temperatures for Carwoola for 3 years so have approximated average temperatures as the mean of average maximum and average minimum for the period 1993 to 2016.
As would be expected that is influenced by the low minima recorded prior to 1997.  Disregarding those years eyeballing the chart suggests variation around a quite flat line for the period 1999 to 2016

Saturday, 2 December 2017

A mesodiluvian post

People use the term antediluvian to refer to the period before (ante) the flood, usually in a Biblical context.  I have used the prefix "meso" meaning middle as this is starting off in the middle of a flood.

I use the term flood as Whiskers Creek has just started to go over the drive.

We have had warning that a dump was coming for several days.  It was mainly a question of "How much".  Yesterday morning we were outside the extreme weather warning area defined by the BoM.  However by mid-day we were just inside the area and there was talk that we might get up to 100 mm out of it.  Other forecasts suggested about half that amount (still significant - probably putting the fall in the top 20 days since 1983 - WOT A PREDICTION!!  see below).

On the evening of 1 December we had a storm come by, dropping 8.6mm.  It then didn't rain until about 5am on the 2nd.   By 10am on the 2nd we had scored another 31.8mm.

I'll begin the imagery with three radar shots from about that time.  The first is the Weatherzone image of 128km around Captains Flat.
 We are just SE of the big yellow blob.  Obviously more to come.

Switching to the BoM site and going out to 256km shows a pretty clear patch to the NW of us.  Perhaps it is going to shut down a little sooner than expected?
 Back to Weatherzone, at NSW level to get the lightning strike information.  This shows a line of really nasty looking storms from Lake Cargelligo to Bourke.
Depending on just how the system moves we might cop those storms (bad) or just the bunch of green around Wagga.  (30 minutes later and it looks as though the line of storms may drop by!)  We shall see: in the meantime here are a few photos from our block.  All were taken around 10am.

 Whiskers Creek is just starting to flood over the road..
It is running strongly below the drive.
We had a period - perhaps 45 minutes with no rain.  Then a reasonably squally period came through.  I believe this is represented by the yellow linear patch in this Weatherzone 128km radar plot.  (I've added a red X for our house.)
The yellow linear feature is the South end of the line of storms shown in the NSW level graphic above.  So with luck that has gone to our North.  At 12:30 the wind had risen also.

By 5pm the sun had come out and we had received 43.8mm for the day (52.4mm for the 24 hours).   Checking the WZ radar ...
.... shows some unpleasantness North of Wagga (Wagga Wagga if you wish to be formal) so we may get a little more yet!  I think everything went to the North as we only got another 0.2mm for the day.

Looking at the 2 days overall shows the two patches of rain.  On 2 December I recorded 44mm: while not "unprecedented" (the day-record for Carwoola since 1983 is 96mm on 10 December 1996) it is the 20th highest daily fall over that period which I think noteworthy.
 The different nature of the two patches is revealed by the rain rate.  The highest rate (for 1900 on 1 December) was 93.6mm per hour which is the 25th highest rain-rate since I started recording in November 2013. (Rain rates weren't available from the older records.)  Again noteworthy.
My final graph of data from my Weatherstation is the external temperature, showing a very steady decline during the day of 2 December.
The final element of this post is from a BoM River Height monitoring station on the Molonglo River, about 2.8km NE of our house (and upstream of the junction with Whiskers Creek).  I have been aware of the data from this station for a number of years but never really looked at it before.  Here is an extract of the data in chart form.
In one of the community Facebook threads about the weather the question was asked "Is the Briars -Sharrow crossing open?" The height of the Molonglo is currently at 1.2m and my understanding is that water is across the road at 1.4m.
What struck me about the graph was the relative suddenness of the rise. Between 6:30 PM and 8PM (after it had finished raining here) the Molonglo rose 0.3m . Looking at the data as a table the interval between readings varies a lot: when the River level is stable (or dropping) it may be up to 3 hours  between readings. However during that period of rising levels the interval was pretty constant at 5 minutes.
So the good news from this is that when it is needed the readings are very timely. A second point is that another surge like the one yesterday evening (0.3m) will get the water well over the road, so check before leaving home.

There has been a bit of discussion (on the community Facebook page and elsewhere) about the cause of the rise.  Opinion seems to come down on the side of it just taking a while for the runoff to filter through the catchment and down to Briars-Sharrow Rd.

This next image is basically here to let me get a URL of the image!

Friday, 1 December 2017

Weather report November 2017

There are a few minor changes to what went in the Gazette,

...  mainly a matter of me solving a computer problem.  The main issue was on the side of the keyboard away from the screen!
I do apologise to all chimpanzees, or indeed any life form more advanced than pond sludge, who wouldn't make a mistake as daft as the one I did!   Whatever, we're back on line!

Mainly a temperate month, with a very welcome serve of rain!


Yes, we got some!  At one stage it looked as though we might get over 100mm for the month but we 'only' got 76.4mm.  This is well above 2016 (and the average for the area since 1983) but slightly below the average of the last 10 years at our place.
 We are now well over 50% of the average rainfall , Year-to-Date.  Although I am very dubious about the statistical validity of projecting a 4th order polynomial with only 11 observations the value of R2 is pretty good.


At an early point in the month I commented that given the cold start, and low forecast temperatures we could be looking at the lowest average minimum ever for this month.  However some warmth arrived later in the month and we didn't achieve that.  Here are the daily extremes which clearly show the warming through the month..
 The next two charts show the average monthly value for maximum and minimum,  The maximum was still a little down ...
 ..  but the minimum, possibly due to the number of wet (or at least cloudy) days, was well up.
Obviously frosts were not an issue and we only had 2 days above 30oC compared to an average of 5 such days.


The chart below shows relative humidity for 3pm in % and rain in mm.  They both (sort of) fit on the same axis.
 As would be expected, in most cases the higher humidity occurs on days on which it rained.  I was a tad surprised at the number of days (11) with rH below 40%.  To my surprise the average rH for the month at almost exactly 50% was greatly above both 2016 and the average of the previous 4 years.


A rather windy month overall (although calmer than August-September this year).
Most of the windy days were early in the month, and there is very little (r2 = 0.35) correlation between wind and rain!

Possibly wanted: good supply of Camphorwood ...

.. and a bunch of animals that'll go in 2x2.

Over the past few days there have been a number of hysterical weather forecasts in the media and other places with headlines screaming about huge amounts of rain and flooding.  Thus ark building has become a popular hobby.

On looking more closely the forecasts have focused on Victoria, rather than our area.  So what seems to be the the forecast for the Eastern part of the Southern Tablelands of NSW?  Note that the interpretation of maps etc is my totally inexpert view and mainly meant for amusement.  Don't plan anything (whether BBQ, boat building or beast bivouacing) on the basis of these words.

I'll begin with the current Extreme Weather Warning from the BoM.
That suggests that the really bad weather doesn't get over the Brindabellas.  Hmmm: perhaps put down the power tools and stop lining up the alpacas!

Next we have the BoM rainfall forecast for Friday 1 December.
 This area is on the cusp of the 1-5mm and 5-10mm ranges.  Probably fair to say about 5mm.  A welcome drop, but if that floats your boat, you have got a pretty small boat.  The camelids can be left unpaired.

On  to BoM forecast rainfall for Saturday.
 Again, our area is pretty close to the margin of two classes.  I'd say we are likely to get around 50mm.  Our records since 1983 show 14 days with that amount of rain or more (the highest was 10 December 1996 at 94mm).  So its going to be one of our damper days, but not unprecedented.  I wouldn't play in a watercourse that day!

Looking at a Norwegian site I am exploring they offer this chart for Hoskinstown.
On Friday the rain is more like drizzle for several hours with the only really significant falls around midnight.  For Saturday the falls are heavier but reasonably moderate totaling to about 48mm.  I'd take a raincoat if going out in the afternoon.  Here is the table underlying that chart.
With regards to wind speed this site quotes metres per second, peaking at 8m/s around 4pm. That is equivalent to ~28 kph which is a reasonable, but not dramatic, speed.

In terms of other Australian sites Weatherzone offers rainfall on Saturday of 10-20mm for Braidwood, Nerriga and Goulburn and 20-40mm for Yass.  Meteye suggests 25-40mm for Carwoola.


Tuesday, 28 November 2017

Kingfishers at work

A pair of Sacred Kingfishers have been very vocal at our place recently and it seemed that they were making the call used around a nest site.  When I went to the sunroom today I found that a large knot on a Yellow Box ...
 .. was being visited.

 On most of the visits I saw the bird seemed to fly and give one peck,  while on others it would perch for several seconds doing woodpecker impersonations.

I'll finish with a couple of portraits,