Tuesday, February 3, 2009

Google Earth goes to sea

I suppose I have to put the disclaimer up "Not intended for navigational use" first, right? Although I did run into a gentleman once halfway up Johnstone Strait who was navigating his way from Seattle to the Aleutians using a second-hand National Geographic "Maps of the World" CD ROM. He was doing all right.

Google Earth, the program that lets you zip and zoom around the globe with a flick of your mouse, now has data covering the depths of the world's oceans. Navigate with it at your peril! As the article says "The addition of the oceans posed many technical hurdles, not the least being aligning disparate data sets so water meets land in the right places, Google engineers said." That information, of course, is sort of the bare minimum I look for in charting solutions, but at any rate this isn't being proposed as such and I don't know why I mention it.

No, I do know why I mention it, actually; I was trying to skimp and save some money last year by avoiding the purchase of small-scale route-finding maps (also not intended for navigation, though Lord knows they cost as much as charts which are) of the Inside Passage by using Google Maps. I was defeated, however, because I found that the location and distinction of the many small landmasses which make up the Inside Passage were so muddled, and the satellite imagery so blurry and indistinct, that there were no clear representations of well-known channels, let alone navigable passages. I broke down and borrowed the route maps, instead.

I hadn't tried the downloadable Google Earth at the time as I assumed it worked from the same data. Operating under the same assumption in reverse, then, I went back today to check out Google Maps north of, say, Port Hardy, and found that there is a world of difference--although some of the sat imagery is still less than pristine (I don't doubt it's hard to find clear days in that neck of the woods; clouds cover some significant patches of the area even on images further south) it is available in considerably more detail--I can actually zoom down in and check out some of our anchorages, including the infamous Boat Inlet. That lighter green patch toward the bottom of the channel, right before it opens up again, are the shoals on which we ran aground. Zoom out a little bit and you'll see how constricted the channel was--once the transmission lever broke, we were committed to going forward until we reached the larger pool at the interior. Unfortunately, we didn't quite make it.

Keep zooming out and you can see where we were in relation to Bella Bella. The Canadian Coast Guard station is where "Old Bella Bella" is marked on Denny Island.

Had everything gone as planned, we would have ducked out into Queen Charlotte Sound the next day and continued north. Funny, it all looks a lot easier on Google Maps....