`The moat in Mandalay is one of the minor beauties of the world. It has not the sublimity of Kilauea, nor the spectacular picturesque of the Lake of Como, nor yet the swooning loveliness of the coastline of a South Pacific island, nor the austere grandeur of parts of the Peloponnesus, but it has a beauty which you can take hold of, and enjoy and make your own."
I was reminded of Somerset Maugham's somewhat pretentious eulogy of this Burmese city by a basso profundo rendering on German radio of Kipling's celebrated verse. You remember the one, of course; it goes:
Come you back to Mandalay
Where the old Flotilla lay;
Can't you hear their paddles chunkin'
From Rangoon to Mandalay.
But Mandalay's celebrity for meteorologists stems from its status as probably the most famous rain-shadow in the world.
Altitude plays a major part in rainfall. Higher than average rainfall occurs near high ground because of the forced ascent of moist air; the resultant cooling causes the moisture in the air to condense, producing clouds and rain. But this surfeit of rain occurs only on the windward side of high ground, a phenomenon that has a beneficial outcome for low-lying areas on the sheltered side of any mountain.
If enough water has been extracted from the air on the ascent, there will often be insufficient moisture for clouds or rain by the time it reaches low ground on the far side. The end result is a region of relatively light rainfall in the lee of high ground - a "rain-shadow" - where it often remains dry when it is raining steadily elsewhere.
Now Mandalay lies in a region which, in general, has a very high rainfall. Rangoon, for example, to choose the other city of Kipling's rhyme, is just a few hundred miles down the Sittang Valley to the south of Mandalay, and experiences an annual total of nearly 5,000 mm of rain, which, to put it in perspective, is about five times that of most places in Ireland.
But Mandalay itself lies on the alluvial plains of the Irrawaddy river, and is surrounded on all sides by high mountains. No matter from what direction the rain approaches, the city is in rain-shadow, and the result is an annual total of less than 700 mm.
But there is another even more intriguing question about Mandalay. It is an inland city, so what on earth did Kipling mean when he wrote:
On the road to Mandalay,
Where the flyin'-fishes play,
An' the dawn comes up like thunder, outer China
`crost the Bay?