Experimental
Rainfall
Recording
Hi Folks,
I am going to try to produce an ongoing graph of the daily rainfall,
over the next few years. I have been thinking of this for quite a while
and think I have a workable solution for my size of operation. I need to
combine accuracy, with robust data collection and storage. To this end I
am collecting the daily incremental rainfall readings from my rain gauge
in a way that I can graph them and also add in the reading of the water
level gauge at Number 2 Ramp.
I am also hoping to be able to record the temperature of the lake water
at this gauge as well to be able to present that in a graph. This is the
trickier reading. As we all know water is constantly leveling across the
whole lake, a 10cm jump at the gauge goes across the whole lake. However
I am expecting that taking the temperature at Number 2 Boat Ramp will be
a somewhat isolated reading and may not be at all representative of the
whole lake. My assumption is based on the fact that the lake is made of
two arms, Toorloo Arm and Nowa Nowa Arm that gradually get shallower as
the tributary entry points are reached. The fish move around seasonally
depending on whether they are spawning or not, just to give one example
of their life cycle effecting distribution. Many people are sure this is
related to temperature.
It will be rewarding to investigate the temperature variation further
and do some samples up the arms and determine what the distribution of
temperatures might be. Spawning may be more related to shallow water and
the feed available for fry in those areas. Anthropomorphism is very hard
to shake off, and we must always be on our guard to avoid quick
assumptions on what would suit us humans e.g. warmth means comfort!
Here is the Rainfall data file if you are interested
rainfall.csv
And here is the beginning of the chart which for the moment will be
updated manually, from time to time.
As you might agree we have had reasonably regular
rainfall but few storms that have really made a difference. The last one
that nearly made it to 70mm over a couple of days was early December
2017. We have a had a few close 40mm's but mostly were around the 10mm
to 15mm. The chance of filling the lake without a considerable storm is
very unlikely as recent rains have barely been keeping up with
evaporation.
Here is a previous analysis from Nov 2017.
The above graph highlights that we have had a
taper off of the rain over winter this year. However Spring rains have
compensated this and the overall rainfall looks fairly average after
all. Significant for the opening is we have not had the Winter storms
of last year with a big rush of rainfall over a short period of time to
fill the lake quickly and make a break in the sandbar. The black line
hi-lights the dip over late Autumn/Winter and the red line hi-lights the
good falls we have had in late Winter and Spring. Generally speaking the
2016/17 Summer rainfall pattern continued through the 2017 Winter.
This time I have chosen to show the rainfall for every 24 hours for the
last 7 months, rather than the cumulative rainfall. As we head towards
another winter, I hope to show that it is the amount of rain that falls
in a short period that influences the level of the lake most. High
rainfall in a short period of time has less time to seep away, whereas
small amounts more frequently has time to seep away under the bar.
However as the sand in the bar gets clogged with micro debris from the
lake less and less seeps away.
Special thank you to the Arduino community for sharing all their good
ideas with everybody else,
Grazie
ragazzi!!! And also to Beck and Daff next door who keeps a
great rain gauge near mine for double checking the electronics system.
Cheers mate!