Friday, November 03, 2006

Scintillating discrete angels

That’s what I’m reading about today. I’m in the Alexander Library of the Edward Grey Institute, part of the Zoology Department of Oxford University.

Phew.

It’s a second home to me, but I don’t get here as much as I’d like. The journey from Cambridge to Oxford is god awful, really it is. You choose between a train journey via London, or a coach journey that takes longer than flying from Boston to London. I collared the driver, once. I came over all selfrighteous and unfolded my timetable and pointed my finger at the floppy paper and demanded an explanation from the driver.
"Look! It says two and a half hours on this timetable!"
"Yeah". He was so cool. "You don't want to pay any attention to that, love, it's rubbish. They don't know what they're talking about".

Creepy old Oxford...

Downstairs at the EGI is a cracking research library, all 1970s wooden tables, yellow striplights, grey metal shelving. I'll take some sneaky pics today—wow, yes, brace yourselves: doesn't it sound exciting?! Bear with me — trust me on this, it's really pretty awesome.

The Library!

So yesterday, in a paper on radar ornithology I read the most bewitching passage. It describes the movements of storm fronts and migrant birds. At this point, of course, no-one knew what these radar plots were, nor what was happening on the screen...

Here it is:

The line first became evident at about 1200hr along the coast near Felixstowe; it then moved inland, increasing in intensity and accelerating gradually until sunset, by which time it had reached nearly 50 miles inland and was moving at 6 knots. A similar line developed over Kent and Sussex, moving inland in a similar way. The whole phenomenon decayed rapidly over the sunset period 1930-2000 hr.
Scintillating discrete angels could be seen breaking away from the line during its strongest period; on the easter side of the northern segment over Hertfordshire and Suffolk, and from both sides of the Sussex segments of the line.
In addition to the line echo the screen was well covered with discrete angels during this day. Most were of the short-lived, or rapidly scintillating kind, and these showed no obvious pattern of movement. However, a well-marked stream of persistent angel echoes could be seen moving up the Thames estuary, and some of these could be tracked for considerable distances, occasionally even across the line echo.

6 comments:

Heidi the Hick said...

This makes my brain crinkle. (I'm kinda dense...what were the scintillating discrete angels? And how can I work that into a sentence today?)

Reid Farmer said...

In aircraft communications, "angels" refers to altitude in 1000s of feet. So if someone asked your altitude you would say "angels 20" for 20,000 ft.

Old Scrote said...

Starlings?

dr. hypercube said...

From wikipedia:
angels - British radar operator's jargon for a large diffuse radar echo, often caused by a flock of birds.

Pluvialis - reading your posts is almost as good as being outside - thanks.

Anonymous said...

Though you don't mention the date (and why should you) I'm pretty sure that what's being described are sea-breeze (not storm) fronts - the line echoes formed by swifts and hirundines feeding on insects in the rising current of air as the fronts push inland. Sorry to be less than scintillating. -
Jonanon

pluvialis said...

Is good to know. Thanks for that! Paper was from very early days, and storm fronts were mentioned; but radar ornithology has clearly moved on considerably since then!