3-year trends to May 2011

Parametric plots of smoothed climate variables at Manilla

“Flooding rains climate peaked here in October 2010”Trends to May 2011.

Smoothed data for spring 2010

Fully smoothed data points for spring (SON) of 2010 are plotted in red on the left edge of the graphs. They show that several variables reached peak values during the season. First, temperature range anomaly reached a minimum in September. Next, in October, daily maximum temperature anomaly reached a minimum, rainfall anomaly a maximum, and Dew Point anomaly a maximum. In November, subsoil temperature anomaly reached a minimum. Cloudiness anomaly may have reached a maximum in that month, but perhaps smoothed December or January values will be higher. Daily minimum temperature anomaly did not peak. Through spring it fell steadily from a high positive value.
In a “weatherzone” post, I noted a tendency for variables to peak in a particular order.
“For a “flooding-rains” peak:

  • First: Daily Temperature Range (min);
  • One month later: Rainfall (max), Cloud (max);
  • Two months later: Daily Maximum Temperature (min), Dew Point (max);
  • Four months later: Daily Minimum Temperature (min), Subsoil Temperature (min).”

Not much is different in this case. In particular, daily temperature range was the first to peak (WHY?), and subsoil among the last. However, the time of rainfall maximum did not precede the time when daily maximum temperature reached a minimum.

Data after November 2010

During summer (DJF) most variables seemed to be moving towards “droughts” but this pattern broke down in autumn:

  • Maximum temperature anomaly did not quite reach normal before falling again;
  • Rainfall anomaly became negative then returned to positive;
  • Cloud anomaly had just one negative value before returning to record cloudiness;
  • Dew Point anomalies accelerated to extremely low values;
  • Temperature range anomaly went very positive before falling slightly;
  • Minimum temperature anomaly fell rapidly, independent of maximum temperature anomaly;
  • Subsoil temp anomaly stabilised at a slightly positive value.

I am surprised that extreme cloudiness and extreme low humidity occur together. I am also puzzled about the weak association between daily maximum and minimum temperatures. This is a worry because daily minimum temperatures provide the most consistent signal of climate change during the last century.

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.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s