I have enormous respect for and faith in the scientific method, in proposing thesis, observing/experimenting, concluding and RECHECKING, always rechecking and reevaluating when data and postulates are at odds. Science is core to my being. Likewise with fact-checking. I tend to do a little research to confirm that data supports my positions, prejudices and beliefs rather than simply agreeing with something because it agrees with my bias and is supported by my limited perspective and experience. I mistrust personal accounts -even my own- because I have seen how easy it is to be deceived, how an angle of observation makes something seem to be that simply is not. I had these beliefs reinforced while on a brief holiday in Florida.
Florida is fairly far south in the USA and I visited my least favorite State less than a week after the summer solstice, that point in the year when the sun’s rays are most direct and a given hemisphere has the greatest amount of daylight. The northern hemisphere’s summer solstice occurs around June twenty-first and of course as we travel farther from the equator the amount of daylight one is exposed to increases. I have lived in ten U.S. States including Tampa, Florida which is located around 28 degrees north latitude and Lansing, Michigan up around 42 degrees north, so I have seen first hand over many seasons some extreme differences in daylight from the winter to the summer solstice. Additionally, I’ve lived extremely east and west in time zones so I understand both experientially and theoretically how two places at the same latitude can have the same amount of daylight but extremely different sunrise and sunset times on the same date.
I’ll use Lansing and Tampa as examples of the north/south daylight divide. On June twenty-first Lansing’s 42 degrees north sunrise/sunset times were 6:02 a.m. and 9:20 p.m. while Tampa’s 28 degrees north were 6:36 a.m. and 8:30 p.m., a difference of nearly 90 minutes. For east versus west let’s use Indianapolis (6:19 a.m. sunrise/9:16 p.m. sunset) and Washington. D.C. (5:45/8:37.) Indianapolis is ~550 miles/900 kilometres west of DC but is in the same time-zone. Indy and D.C. had nearly the same amount of daylight but the time interval from sunrise to sunset varied by over 35 minutes on both ends. While this is literally elementary school stuff lots of folks fail to grasp even these basic facts of light and while in Florida I had a brief conversation with a new arrival from the north who was shocked at how little difference in daylight hours there is between his former stomping grounds in Hartford, Connecticut and Florida.
I assured the man that the difference in daylight between Hartford and Tampa on June 21st is roughly ninety minutes but he wasn’t buying it. “Nope,” he declared, “I lived in Hartford for decades and I know sunset is around 8:30.”
“Okay,” I replied, “I lived in Hartford for a while too. I’ll give you that. What about sunrise?”
The man shrugged a shoulder as he lifted a brow, declaring, “I guess they’re about the same too, but I wouldn’t know. I’m retired. I gave up on sunrises five years ago.”
“Uh,” I replied. “I’m an early riser. You might want to check that.”
He said he might, but I doubt he did. I did. Hartford’s summer solstice sunrise/sunset times are 5:18 a.m. and 8:29 p.m.. The sunsets are nearly identical but Hartford gets an additional 80 minutes of daylight in the a.m. while he’s snoozing, a state of being far too many of us default too.
BTW- Another confusing astronomical factor is that sunrise/sunset gain and loss is capricious. Our sunsets can become later in the day as summer progresses even as the hours of daylight decrease. This can also cause those who sleep in to think that we have more daylight as summer progresses than we do on the solstice, an observation that I’ll choose to describe as “‘parochial.”