Saturday, September 12, 2009

The rain in Spain...

... may fall mainly in the plain, but in Alaska it rains along the coast.

About ten years ago, Nancy and I visited Europe. We landed in Munich on a gray, soggy day. It had been raining continuously, we were later told, for several weeks. But then an amazing thing happened. As we got off the plane, the rain stopped and the cloud cover started to thin. By the time we cleared customs the sun was shining, and since then we have had an almost uninterrupted streak of good luck with the weather whenever we have travelled. It has really been quite amazing.

Today our luck finally ran out. When we arrived in Juneau, Alaska this morning it had started to rain, and it hasn't stopped all day. Our excursion to the Mendenhall Glacier was cancelled, but not before we had driven to the airport and donned ice-hiking gear, including crampons and a harness. The day was somewhat redeemed by an absolutely fabulous dinner at a place called the Twisted Fish. If you're ever in Juneau I highly recommend it. The cocoanut salmon is almost worth the trip.

Juneau is actually a pretty amazing place. It's on the North American continent, but you can't reach it by road. The only way to get here is by air or sea. Nonetheless, it is the capital of Alaska, one of only two state capitals that is not accessible by road (the other, of course, being Honolulu). There seem to be only two kinds of businesses in town: art galleries and bars.

We're told this weather is not at all unusual. What is unusual, in fact almost unheard of this time of year, is sunshine. So it will give you some idea of how powerful our travel weather juju has been up until now when I tell you that we actually saw the sun yesterday in Ketchikan (of bridge-to-nowhere fame) for about five minutes. All of the locals were in the street gazing open-mouthed at the sky as if it were the Second Coming. (Yes, I am kidding about that. Now, I am not (at least as far as I know) kidding about how rare sunshine is up here.)

Which brings me back to Fjords. There are only four places in the world that have fjords: Norway, Alaska, Chile and New Zealand. Why is this? It because fjords are valleys carved out by glaciers. To make a glacier you need a lot of ice. To make a lot of ice you need a lot of precipitation and cold temperatures. To get cold temperatures you have to be far from the equator. And to get a lot of precipitation you need a mountain with a large body of water to the west. Why? Because the prevailing winds on planet earth blow from west to east. You can get sporadic precipitation from a lot of different sources. But to get the kind of sustain precipitation that you need to make a glacier the only way to do it is to tap into the water that has just evaporated from an ocean. The way you do that is you take the moist air from the ocean and force it upwards. As air rises, it cools, and any moisture it contains condenses out. And the easiest way to force air upwards is to take a mountain and put it in the path of the prevailing wind. Norway, Alaska, Chile and New Zealand are the only four places on earth that have the necessary ingredients to make glaciers: mountains far from the equator facing west adjoining an ocean.

So fjords, along with earthquakes and the Hawaiian islands chain, are another puzzle for young-earth creationists. If you want to argue that fjords were created by, say, Noah's flood, then you have to come up with some other explanation for why fjords are found in exactly these four places and no others, since glaciers require a very long time to form (and a long time to disappear again). 6000 years is nowhere near enough.

2 comments:

John Dougan said...

Ummm....no. Those are not the only places with fjords. At the very least a quick glance at a globe will show that there are a bunch down the British Columbian coast. The Wikipedia article on Fjords has a complete list.

Ron said...

> a quick glance at a globe will show that there are a bunch down the British Columbian coast.

Oh, give me a break. It goes without saying that geological processes don't respect political boundaries. When I said "Alaska" I meant "Alaska and nearby areas". BC is just south of Alaska.

The point is: fjords are found *only* at extreme northern or southern latitudes, and *only* on west-facing coastlines.