Summertime convection

Have you ever thought that for aeroplane pilots, every day at work is a blue-sky day? Soaring above the clouds you might think that the weather isn’t such a big deal. But this couldn’t be further from the truth. Pilots are dependent on weather information at every stage in their flights. In this blog post, we discuss one crucial aspect of aviation weather that affects both pilots and passengers – turbulence.

The nature of turbulence

In the English language we have many words in common usage that have related but more specific meanings in a scientific and mathematical context. The key word of this blog post, “convergence”, is a good example of this. We sometimes hear of people’s views on some matter initially disagreeing and then, later, coming together or “converging”. In fluid dynamics we’re often interested in regions where different air flows come together. We call this type of flow convergence, and say that the air is converging. 

August 2012

One evening, having just arrived home after the short walk from Trentham Station, I remarked to my family that it was unusual for the wind to blow from the northeast in Upper Hutt. Five days later and it was still blowing from there.

In the days following Wednesday 6 July 2011, stormy westerly conditions affected New Zealand. In this blog, we'll look at why.

The "Long Waves"

Below is the mean sea level analysis - the weather map - for 6am Sunday 10 July. In between big highs over the mid South Pacific and south of western Australia is a really large trough; it's the area shaded light blue. The weather map looked like this, more or less, since Wednesday 6 July: that is, the big features on it aren't moving much.

Written by Chris Webster, Meteorologist