July 2015 cloudy and cool

Photo sequence of Wood Ducks and ducklings

Wood Ducks Predator Drill

After a week of fine weather, most of the month was overcast, with cool days and warm nights. One day was very cool, 7 degrees below normal. Later, to make up for that, one night was 7 degrees above normal. There were 13 frosts (usually 17).
The news was full of items about cold weather. In fact, the weekly average temperature was not low here.
It rained on ten days, but never more than 6 mm.

Weather log for July 2015

 Comparing July months

For monthly averages, the most remarkable was the cloudy mornings: 55%. Even that was not as high as in July 2010, which had 61%.
The mean daily maximum temperature was just one degree low and the mean daily minimum one degree high. That made the daily temperature range a narrow 13.2 degrees. This also was not quite as narrow as in July 2010.
The rainfall of 18.0 mm was in only the 21st percentile, but it was higher than in last July or in three other recent July months. This month, one rainfall total has fallen into the 9th percentile (a serious shortage): the 24-month total of 984 mm.

Climate for July 2015


Data. All data, including subsoil at 750 mm, are from 3 Monash Street, Manilla. Rainfall data up to 26/3/15 is from Manilla Post Office, Station 055031.

3-year trends to July 2015

Parametric plots of smoothed climate variables at Manilla
“July 2015: cooler, moister trend”

Trends to July 2015

July raw anomaly data (orange)

The near-normal values of June are now seen as merely interrupting a trend to cooler, moister climate. July had very low day temperature, very high cloudiness, and very low daily temperature range, but dew point was not extreme. Discordantly, rainfall, which had been very high in June, became very low in July.
Night-time and subsoil temperatures continued their trends towards higher values. (Relatively warm nights have now persisted for 17 months.)

Fully smoothed data (red)

January 2015 was relatively cooler by day than the previous month, but each of the other variables moved only slightly down the graphs.

El Niño

In this record, the last hot dry climate phase that matched an El Niño was in November-December 2009. At that time, the daily maximum temperature anomaly was very high, the rainfall anomaly was low, and the daily minimum temperature anomaly (lower left graph) was a record high.
Later, in November-December 2013, without an El Niño, Manilla had a more extreme hot dry climate phase. As seen on these graphs (marked in blue), 21st century records were set then for anomalies of high daily maximum temperature, high subsoil temperature, and low dew point.
Now, in July 2015, an El Niño is forecast, but these Manilla graphs show no movement as yet away from cool moist climate.


Note:

Fully smoothed data – Gaussian smoothing with half-width 6 months – are plotted in red, partly smoothed data uncoloured, and raw data for the last data point in orange. January data points are marked by squares.
Blue diamonds and the dashed blue rectangle show the extreme values in the fully smoothed data record since September 1999.

Normal values are based on averages for the decade from March 1999.* They appear on these graphs as a turquoise (turquoise) circle at the origin (0,0). A range of anomalies called “normal” is shown by a dashed rectangle in aqua (aqua). For values in degrees, the assigned normal range is +/-0.7°; for cloudiness, +/-7%; for monthly rainfall, +/-14 mm.

 * Normal values for rainfall are based on averages for the 125 years beginning 1883.

Hot Days and ENSO

Graphical log of max temps and hot days

More frequent hot days do not come in a three year cycle, but in a 1.5 year cycle related to ENSO.

The Hot Day data set

The graph of number of hot days per year

Log of annual hot days in 16 yearsThe graph on the left is one I posted earlier. The height of each data point represents the number of hot days in a year, plotted near January. The pattern of points led me to join them by a smooth curve. This curve swings up and down rather regularly, with five peaks and five dips in the fifteen years. That is, more frequent hot days seem to come in a three-year cycle.
Is this cycle “real”? Should we look for a cause? Will the cycle continue?
Probably not! The points of measurement are one year apart. Cycles that are only three years long may be “aliases” of different and shorter undetectable cycles. (See Note below on Nyquist frequency.)

More detailed hot day data

Other graphs already shown include further data: the number of hot days in each month, and the 13-year average number of hot days in each calendar month. From these I have calculated a relative frequency. That is, the ratio of the actual number to the average number for that month.
Only the months of November, December, January and February have enough hot days to calculate a relative frequency, but these can show changes within the hotter months of each year.

The daily maximum temperature data set

A graph that I posted in “El Niño and my climate” shows a curve of smoothed monthly means of daily maximum temperature anomalies. The yearly cycle of summer-to winter temperature has been removed. I have also applied a smoothing function, which makes the monthly points of measurement effectively two or three months apart. As a result, cycles longer than about six months can be detected.
There are about 10 peaks and 10 dips in the 15.5 year curve. They define a cycle of about 1.5 years wavelength. That cycle is so much longer than the minimum-detectable six month cycle that “aliasing” is not likely.
The reality of this temperature curve is supported by its close similarity to the recognised curve of the El Niño – Southern Oscillation (ENSO), as read from NINO3.4 Pacific Ocean sea surface temperature anomalies.

A combined graph of hot day and temperature data

The graph at the top of the page presents the monthly smoothed maximum temperature anomaly again, using the scale at the left. To this I have added data on the number and frequency of hot days.
The annual number of hot days is shown in blue, in blue boxes. The boxes are placed higher or lower according to the number, but the height is adjusted to match other data better.
A “Hot Day Index” is shown by blue diamonds. This index is based on the relative frequency of hot days in each month that has data.  I have re-scaled the values to improve the match. (See Note on Re-scaling below.)

Matching hot days with temperature

Continue reading

El Niño and My Climate

ENSO and Manilla NSW temperature anomalies over sixteen years

Temperature

The first graph shows that the temperature at Manilla NSW agreed very closely with El Niño and La Niña temperatures for a good part of the last sixteen years.
The El Nino – Southern Oscillation (ENSO) is shown by NINO3.4 monthly anomaly values, and temperature at Manilla, NSW is smoothed monthly mean daily maximum temperature anomalies. (See the Note below.)
Values of Manilla temperatures agree with those of ENSO through the major temperature peaks and troughs in the spring seasons of 2002, 2006, 2007, 2009, and 2010. In the two highest peaks of 2002 and 2009 and the deep trough of 2010, Manilla temperature extremes were more than a month ahead of ENSO temperature extremes.
Since mid-2011, the two curves do not agree well:
* A La Nina in summer 2011-12 that was very weak produced the deepest of all troughs in Manilla temperature.
* An El Nino in winter 2012 resulted in heat at Manilla, but not until four months later.
* In spring 2013, when there was no El Nino at all, Manilla had a heat wave just like those with the El Nino’s of 2002 and 2009, .
The record for ENSO since January 2013 is unlike that earlier this century: it flutters rather than cycles.
To show slower changes, I have drawn cubic trend lines for both of the variables. These also agree closely, with ENSO going from a maximum (2004) to a minimum (2011) seven years later. Manilla temperature trends remained ahead of ENSO temperature trends by one or two years.

Rainfall

ENSO and Manilla NSW rainfall anomalies over sixteen years.

Continue reading

June 2015 rather wet

Photo of the tiny blossoms of the Wilga, an Australian shrub

Wilga blossoms in June

The first week of June was cold but sunny, the second warm, and the rest not quite so warm. Rain registered (unofficially) on the 17th was 54.5 mm. That was close to the record June day of rainfall at Manilla Post Office: 55.1 mm on 18/6/1930.
The early morning minimum of the 17th was extremely warm, at 12.8°: the fifth warmest for June. There were 12 frosts (as usual) but none was severe. On two mornings, fog persisted past nine o-clock.

Weather log for June 2015

 Comparing June months

Most monthly averages were near normal. Daily minima were up one degree, and morning dew points down one degree.
While lower than in June 2013, the total rainfall of 74.4 mm is high: in the 82nd percentile. Among rainfall totals for more than one month, there are no serious shortages. The lowest percentile value (11th) is for the 24-month total of 996 mm.

Climate for June 2015


Data. All data, including subsoil at 750 mm, are from 3 Monash Street, Manilla. Rainfall data up to 26/3/15 is from Manilla Post Office, Station 055031.

3-year trends to June 2015

Parametric plots of smoothed climate variables at Manilla
“June 2015: back to normal”

15JunParam

June raw anomaly data (orange)

Nearly all raw anomalies for the latest month are nearer to normal than the partially-smoothed anomalies of the autumn months. They are also quite close to the smoothed values of a year ago. Rainfall stands alone as a high value.

Fully smoothed data (red)

In December 2014, most anomalies were normal, or near normal, and changing only slowly.


Note:

Fully smoothed data – Gaussian smoothing with half-width 6 months – are plotted in red, partly smoothed data uncoloured, and raw data for the last data point in orange. January data points are marked by squares.
Blue diamonds and the dashed blue rectangle show the extreme values in the fully smoothed data record since September 1999.

Normal values are based on averages for the decade from March 1999.* They appear on these graphs as a turquoise (turquoise) circle at the origin (0,0). A range of anomalies called “normal” is shown by a dashed rectangle in aqua (aqua). For values in degrees, the assigned normal range is +/-0.7°; for cloudiness, +/-7%; for monthly rainfall, +/-14 mm.

 * Normal values for rainfall are based on averages for the 125 years beginning 1883.

Constructing My Solar-passive House

Photo of tossing a brick

One Brick Thermal Mass

The “Indoor climate” posts on this blog relate to the particular house that I live in. Mainly by luck, it has proved to need very little energy indeed to remain comfortable in all seasons.
Recently, I have collected and arranged photos of the house so that people can see what kind of a house it is.
These photos are accessed by way of “My House Page”.

House footings on a rise

Footings View East

In the last few days I have uploaded photos of the stages in the building of the house. They are in two galleries. The first, “Building Photos: Start” covers from preparation for building up to the erection of timber frames. The photo on the left, showing some of the footings, is an example.

The second new gallery, “Building Photos: Finishing” covers from laying bricks for thermal mass walls (as in the photo at the top) to the completion of an acrylic textured coating on the walls.

Photos of the completed house, inside and out, had been posted already, in “Award photos 1999”.

Once an “Indoor Climate” post or page has been accessed on this web-site, links to all others appear. A post such as this one, when accessed through “Home” will not link to the others until it is selected positively by clicking its title line.