by Doug Ashbury
Northern News Services

NNSL (Apr 29/98) - As the days get longer, get ready for a lot more squinting.

Michael Schaffer, senior meteorologist with Environment Canada's Arctic Weather Centre, says Yellowknife is gaining about six minutes of daylight a day at this time of year.

On Thursday, the city will get 16 hours and 20 minutes of daylight. Sunrise is 5:26 a.m. tomorrow while sunset is 9:46 p.m.

On June 20, Yellowknife will get 20 hours and five minutes of daylight with sunrise at 2:37 a.m. and sunset 10:42 p.m.

Despite official sunrise and sundown, there will be a lengthy stretch when several days known as perpetual twilight. Yellowknifers will be in the gloaming each day for just over seven weeks.

Civil twilight (there are three legal definitions of twilight -- civil, nautical and astronomical) in Yellowknife stretches from May 28 to July 17.

All this daylight likely means loads of sunshine.

And that means your eyes are subject to the sun's harmful rays.

But there is protection available.

Good sunglasses ward off the dangers of intense sunlight and drying winds. They also lessen the chance of airborne debris clogging up your cornea.

As dust season in the capital approaches, that's something to think about.

Optician Ken Morrison says expect to pay at least $100 for a good pair of shades.

It may sound like a lot, he adds, it's worth it.

Lenses in cheap sunglasses (the $19.95 kind) are "stamped out of a sheet that has been dipped or sprayed with ultraviolet protection," he said.

After a few rubs, the UV protection has been wiped off, he said.

Pay more and you will get sunglasses with lenses ground to a standard. The UV barrier will be part of the eye wear.

And for people looking for adjustable shades, there are photochromatic models that go darker when you step outside into all that bright Northern light.