Week 23 [Part One]: Meteorology

Brrr it's cold.

It's safe to say that mid-January has brought a sizeable quantity of very cold, thick and low level fog to the British Isles and there's nothing more fun than needing to feel it's cold embrace as you scrape away the ice from your windscreen (sarcasm).

The presence of the fog itself though is rather apt. It links nicely to the very large topic of Meteorology (Met) which my CP and I have been studying over the past week and a half. I've found it fascinating but it certainly becomes complicated when you're given a set of data and you need to figure out what's going to happen next. 

The building blocks...

When learning Met you begin with the relationships between the four core principles that make up the Earth's weather system. Those are Pressure, Density, Humidity & Temperature. Some of these principles we've already explored within topics such as Principles of Flight and General Navigation but you look at them more closely in Met to understand how differing amounts of each have an impact on our atmosphere. Where pressure is concerned for example, we looked at where areas of High and Low pressures form around the atmosphere (as drawn on the map above) and how these pressures impact the winds and local weather systems. 

Building on the principles we then began to look at Frontal Systems which are very important to both aviators but are also quite appropriate for us as Brits given it's the most common weather system seen witnessed here. You can see the development within a front on the graphic above. As cold air passes warm air it forces the warm air to rise which sparks the development of several differing clouds and poor weather conditions lasting up to 24 hours in many cases. 

These cold frontal systems are also the prime spot for a pilot's worst enemy, the largest cloud form out there: the Cumulonimbus (CB). I can guarantee you've seen CB clouds before. They look all nice and fluffy (as above) and appear to grow in a vertical sense for miles on end. They often top off looking a bit like a mushroom or a blacksmith's anvil but whilst they can be pretty in appearance, don't let looks deceive you. As a pilot you'd certainly be sorry if you were to ever fly through one and thus we're told to avoid them like the plague. They can, and often do, exceeds heights of 30-40,000ft meaning that in some cases airlines can't even fly above them. 

Weather wise, a CB is responsible for never ending torrential downpours, flooding, thunderstorms, heavy winds, snow and even hail as large as small golf balls (pictured below) although thankfully the latter doesn't tend to affect us as much in the UK. Most moderate to severe turbulence occurs in their presence too!

Of course, this is only a small amount of what was covered. We also looked at what occurs in other regions too, such as Africa, the Mediterranean, Australia, and Asia. This included looking at the formation of Tropical Revolving Storms, the existence of the 'Intertropical Convergence Zone', Winds and more. In addition to the theory itself, we also took a look at the more operational side of things, such as weather forecasts and reports given to pilots (METARS and TAFS) and the various charts we'll be using on the line as pilots.

If you're interested, here's the full list. I think you'll agree when I say it's a big topic!

• The Atmosphere
• Heating of the Atmosphere
• Pressure, Density, Humidity, Temperature
• Cloud Formation & Classification
• Precipitation
• Thunderstorms
• Icing
• Visibility
• Wind
• Local Winds
• Upper Winds
• Turbulence & Windshear
• Pressure Systems
• Air Masses
• Fronts
• Frontal Depressions
• Non Frontal Depressions
• Climatology
• METARS / TAFS / Charts

Up next: Operations.

The next ATPL topic we are to look at is Operations. I'm quite looking forward to this as it's more directly linked to the airline world. We'll be covering things such as Flight Crew duty periods all the way through to Dangerous Goods and as usual, i'll try to write another blog post for you all after we've finished it.

Until then,

George.