Like many others, my family and I traveled for the holidays. Let’s see if you can figure out where we are. I’ll give you a few hints.
This morning (I’m writing early Friday morning, hoping to make my deadline), I’m expecting a beautiful sunrise at 7:16 am, which I’ll be sure to get out to see. In the Grand Haven area, the sun will rise an hour later, at 8:16 am. Probably it will be cold and cloudy in Grand Haven (I’ve not looked up your weather forecast), so I don’t know if you’ll get out to catch the sunrise.
Later today, at precisely 12:29 pm my time, halfway between sunrise and sunset, the sun will reach it’s highest altitude. This is called solar noon. At solar noon here, the sun will be 40 degrees above the horizon.
Solar noon in the Grand Haven area today is a bit later, at 12:46 pm, and then the sun will be just 23 degrees above the horizon.
Tonight I’ll be sure to get out to see a nice sunset at 5:45 pm. In the Grand Haven area today, sunset is at 5:18 pm.
Today I’ll see the sun for most of the 10 hours and 29 minutes it will be above the horizon; you’ll have sunlight for just 9 hours and 2 minutes.
Have you figured out where my family and I are spending the holidays this year? Here is another hint: we’ve not seen a snowflake since the plane that flew us here was on its takeoff roll last Saturday. We got out in the nick of time.
Here’s how the numbers add up. Recall that our round earth is mapped out by lines of latitude and longitude. Pardon me if this is a review, but so we’re all on the same page, it goes like this. Lines of latitude run east-west parallel to the equator and map how far north (or south) of the equator a place is. Lines of longitude run north-south, wraping around earth, all passing through the north and south poles. Longitude maps how far west (or east) from Greenwich, England a place is. (Why Greenwich, England? I don’t know, off hand).
Notice that at solar noon where I am the sun is 17 degrees higher in the sky than it is at solar noon in the Grand Haven area. This betrays the fact that my family and I have travelled to a location that is 17 degrees of latitude south of Grand Haven. Grand Haven’s latitude is about 43 degrees (N).
Notice that solar noon occurs where I am about 15 minutes before it does in Grand Haven. The east-rising/west-setting of the sun is a consequence of earth’s daily west-to-east rotation. Earth spins 360 degrees in 24 hours, so at a rate of 15 degrees per hour. The quarter hour difference between my solar noon and yours betrays the fact that my family and I have travelled to a place that is about 4 degrees lof longitude east of Grand Haven. Grand Haven’s longitude is about 86 degrees (W).
Where are we? Latitude 26 degrees (N), longitude 82 degreees (W) – Punta Gorda, Florida.
It’s warm and sunny here. Warm and sunny because the sun is higher above the horizon all day long here compared to West MI. Very nice.
I hope you are enjoying the holidays. And as nice as it is here in Florida, our return to the land of snow and ice is surely going to be harsh.
This column originally appeared in the Grand Haven Tribune on 26 December 2008.
