3-year trends to August 2010

Parametric plots of smoothed climate variables at Manilla
“Summer retreated from drought”

Trends to August 2010.

Manilla’s recent climate continues to be marked mainly by cloudier skies and a narrower daily temperature range than in the 12-year averages.
In the current plots we see final smoothed trends for summer (DJF) of 2009-10.

Daily maximum temperature anomaly is shown on the x-axis of each plot. The minimum value in Feb 2008 (-1.61) and maximum value in Nov 2009 (+1.35) are also the extremes (in blue) of the smoothed data set. In summer 2009-10 the smoothed temperature anomaly fell much faster than it had risen in the previous winter and spring. During autumn the max temp anomaly was near zero, and the raw value for August is so low (cold) the scale has had to be extended.

Monthly total rainfall anomaly is on the y-axis (inverted) of the first graph. It showed a very mild drought throughout the last winter, spring, and summer. Autumn seems to have been less droughty, much like the previous autumn, but with the opposite trend. Recently, July 2010 was very wet, but August rainfall was normal.

The anomaly of per cent cloudy mornings fell during winter 2009 as the maximum temperature anomaly rose. During summer 2009-10 it rose again as the maximum temperature anomaly fell. However, for a given maximum temperature anomaly the cloudiness anomaly was now more positive (it was cloudier). Since the end of summer, skies have been extremely cloudy

On the graph for early morning dew point anomaly, the final year’s data plots like that of the cloudiness graph. However, dew point anomalies were not so positive: in winter and spring 2009 they were quite strongly negative. By autumn 2010, dew points seem normal, and recent values are high (humid climate).

For daily temperature range anomaly, again, the last year’s pattern on this graph is like that on the previous two graphs. In this case, values low on the graph are negative anomalies, representing narrow daily temperature ranges. For a given maximum temperature anomaly, the anomaly of daily temperature range was lower during the summer than it had been the previous winter.

(Note on the “Macquarie Island” label. This August  Manilla’s anomalously low maximum temperature (16.8°) is actually much higher than that of Macquarie Island (5.0°), and the anomalously narrow daily temperature range (11.9°) is still much wider than that of Macquarie Island (3.5°).)

In the case of daily minimum temperature anomaly, summer 2010 began with a maximal value, and the value stayed high through the season. Values may have been lower in autumn, then they seem to have risen even higher (very warm nights).

World-wide low temperature

At Manilla, in early 2008  there were record low values of daily minimum temperature, daily maximum temperature and subsoil temperature. These did NOT come with high rainfall and high dew point as would occur in a “flooding rains” peak of the quasi-biennial oscillation. They match low temperature at that time world-wide.

Subsoil temperature anomalies have remained close to zero for 17 months, despite big changes in the anomalies of other temperatures.

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.

3-year trends to July 2010

Parametric plots of smoothed climate variables at Manilla
“Extraordinarily moist”

Trends to July 2010.

The July 2010 raw data, (orange) shows an extraordinarily moist month. Anomaly values of rainfall, cloudy days, Dew Point, and temperature range are so extreme that the graph margins have had to be moved. The Minimum temperature anomaly is also extraordinarily high, but this result is not so clearly linked to moisture.
Extreme moisture is usually associated with low maximum daily temperatures, in the “Flooding Rains” corner of the graphs, but this July the maximum temperature is not extreme, but normal.

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.

3-year trends to June 2010

Parametric plots of smoothed climate variables at Manilla
“Back from a very mild drought.”

Trends to June 2010

Raw data for June 2010 (orange) are mainly near the smoothed values for January 2009, 17 months earlier. As an exception, the minimum temperature anomaly was very high, making the daily temperature range very low.

The last fully-smoothed data point, December 2009 (red), had hot days with a slightly lower daily maximum temperature anomaly than the record set the month before. Rainfall anomaly during this “drought” peak was not very low at all (-16 mm). Other variables for November 2009 were near normal, except daily minimum temperature anomaly, which was a record high value of +1.31 degrees.

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.

3-year trends to May 2010

Parametric plots of smoothed climate variables at Manilla
“Temperatures normal”

Trends to May 2010

Manilla’s climate in the last three years has been marked mainly by cloudier skies and a narrower daily temperature range.

Raw anomaly values for climate variables for May 2010 (orange) were normal for daily maximum, daily minimum, and subsoil temperatures and for daily temperature range. Rainfall and humidity (dew point) were rather low, but skies were very cloudy.
Fully-smoothed data (red) for November 2009 showed a record value for daily maximum temperature anomaly, which seemed likely to be a peak value.

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.


(Note added in May 2014:

This post titled “3-year trends to May 2010” is the first of a consecutive series of parametric plots, updated monthly at the time of observation and originally posted elsewhere.
Data exists back to March 1999, but the earlier data was not edited in this form at the time.
To display all existing fully-smoothed data points at least once, I have prepared back-dated posts in this same format for:
“3-year trends to August 2002” which includes smoothed data September 1999 to February 2002, covering the calendar years 2000 and 2001.
“3-year trends to August 2004” which includes smoothed data September 2001 to February 2004, covering the calendar years 2002 and 2003.
“3-year trends to August 2006” which includes smoothed data September 2003 to February 2006, covering the calendar years 2004 and 2005.
“3-year trends to August 2008” which includes smoothed data September 2005 to February 2008, covering the calendar years 2006 and 2007.)

3-year trends to August 2008

Parametric plots of smoothed climate variables at Manilla
“Years with unusual trends”

Trends to August 2008

These graphs, ending with raw data for August 2008, show fully-smoothed data from September 2005 to February 2008. They include all months of the calendar years 2006 and 2007.
Smoothed daily maximum temperature anomaly (X-axis on all graphs) began 2006 high in the “normal” range, fell to normal by June, and rose again to +0.63°  in November and December. It then fell from high to very low through 2007, reaching the record low value of -1.61°  by February 2008. (Note added: This record low maximum temperature anomaly stood for only 19 months, until September 2010.)
Smoothed rainfall anomaly peaked at +20.6 mm in November 2005, fell rapidly to -11.7 mm in June 2006 and slowly to -14.6 mm in October 2006. It rose again to just above normal by February 2007, and changed little in the following year.
Smoothed percent cloudy mornings followed a similar course to that of rainfall but, as temperature fell through 2007, cloudiness (unlike rainfall) increased, as is normal,  along the blue trend-line.
(Note added in May 2014: Although the minimum value of the cloudiness anomaly in August 2006 (-7.7%) is less negative than the record minimum in August 2002 (-11.3%) (or even than the minimum in February 2005 (-9.1%)) it is more negative than any later value. No smoothed negative values at all were recorded in almost seven years between February 2007 and October 2013.)
Smoothed dew point anomaly also followed a similar course to that of rainfall but, unlike cloudiness, actually declined as temperature fell during 2007. Temperature range anomaly moved like dew point anomaly.
Daily minimum temperature mainly varied in the same sense as daily maximum temperature, but at a higher rate. As an exception, from January to June 2007, it rose slightly as maximum temperature fell. That moved the curve towards a more “maritime” climate for the rest of the time. Subsoil temperature anomaly moved in a similar pattern.

Unusual trends

Through the years 2006 and 2007 shown here, the climate moved as much along the axis from top left to bottom right, as along the usual axis from top right to bottom left. It departed from the typical Quasi-biennial oscillation of “droughts and flooding rains”*. (Note added: The extreme negative maximum temperature anomaly of February 2008 was the only one on this record that was not linked to an extreme positive rainfall anomaly.)
(Note added concerning global temperature: At this time there was a sudden major cooling in mean air temperature, both locally and globally. This linked post  shows that, when 37-month averages of global and local values are plotted, mean temperature fell from a peak in April or May 2006 to a trough in October 2007, breaking the global warming trend. The global (GISS) value fell by 0.074° (and the Manilla value by 0.48°). The connection is enigmatic. The unusual trends shown here do not match the dates of the cooling event, but come mainly before or after it.)

* By arrangement with the Licensor, The Dorothea Mackellar Estate, c/- Curtis Brown (Aust) Pty Ltd.

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.
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.

(Note added in May 2014: A much later post titled “3-year trends to May 2010” is the first of a consecutive series of parametric plots, updated monthly at the time of observation and originally posted elsewhere.
This earlier data was not edited in this form at the time.
To display all existing fully-smoothed data points at least once, I have prepared these back-dated posts in the same format for:
“3-year trends to August 2002” which includes smoothed data September 1999 to February 2002, covering the calendar years 2000 and 2001.
“3-year trends to August 2004” which includes smoothed data September 2001 to February 2004, covering the calendar years 2002 and 2003.
“3-year trends to August 2006” which includes smoothed data September 2003 to February 2006, covering the calendar years 2004 and 2005.
“3-year trends to August 2008” (this post) which includes smoothed data September 2005 to February 2008, covering the calendar years 2006 and 2007.
In these back-dated posts the anomaly values depend on climate normals that are based on the decade ending February 2009, and were thus not available until after that date. I have written the posts as if they were available at the time.
In places I have written some “Notes added in May 2014” (like this) commenting on how values observed at that time relate to more recent events.)