At the winter solstice for the northern hemisphere, the Sun is over the Tropic of Capricorn at 23 degrees 26 minutes south. Your observer is at 38N, a difference in zenith angle of 38+23.5=61.5 degrees. The elevation of the Sun above the southern horizon at noon (more precisely "Local Apparent Noon") is 90 - the azimuth angle, or 28.5 degrees.
Noon by your clock probably isn't "local apparent noon", the time when the Sun is in transit - at its highest point in the sky. For example, I live near Sacramento, CA, and here, in daylight savings time, the Sun transited my longitude at 12:57PM today. If I were a sailor (which I used to be) I could take a single "noon sight" of the Sun and calculate my position quite accurately with a single observation.
I need to watch the Sun through my sextant, and take continuous readings of the elevation angle of the Sun. (On the deck of a pitching boat, this observation can be tricky!) I note the time when the Sun is no longer rising in the sky, and starts to set; that time, to the nearest 15 seconds, gives me my longitude. The elevation angle at that time tells me my latitude. I do need to have an accurate watch, and a copy of the Nautical Almanac, but every modern sailor has these things.
Back in 1714, the British Admiralty offered a prize of twenty thousand pounds - a king's ransom, back then! - for the invention of a clock that kept accurate time at sea, because your celestial position is only as accurate as your clock!
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