EDITOR'S NOTE: This story originally appeared in 2014.
This might very well be one of the toughest Mondays of the year.
If you wake up before 7 a.m., it certainly will be a lot darker than it was at the same time Friday morning.
And you might feel like you didn't get enough sleep this weekend, because, well, a whole hour vanished into thin air.
Brighter days are ahead.
"After the winter we've had, I think right now we really need this," said Kim Rosenberg, a licensed psychologist in Lancaster.
"This" is daylight saving time, which arrives at 2 a.m. Sunday.
In keeping with the reminder to "spring ahead," 2 a.m. instantly became 3 a.m.
For some, the arrival of daylight saving time is a sign that winter is waning and spring is just around the corner, Rosenberg said.
It puts many of us in a better frame of mind than we were in just last week, because, although we'll probably wake up in the dark for the next couple of weeks, there's more light during the evening hours after work.
And going forward until June, sunrise will come earlier each day, while the sun will set later and later.
"In part, the light really does affect our mood," Rosenberg said. "We have more of it in our waking hours, and that can make us feel better — more positive."
Jane Clipman is an adjunct instructor in Millersville University's psychology department.
"I look forward to daylight savings time," Clipman said. "It makes me feel wonderful.
That said, however, Clipman noted the research she found on daylight saving time and mood indicates Monday typically is harsh.
The Monday after daylight saving time, she said, is associated with:
• a higher incidence of traffic accidents;
• more work related injuries;
• a higher rate of heart attacks;
• a drop in stock prices;
• more cyberloafing on the job;
• a decline in rating of personal happiness among people who work full time — early risers reported hating the once-again dark mornings.
"These outcomes have been blamed on the lost hour of sleep and the resultant lack of attention, poor mood, and increased stress hormones," she said.
"None of the differences are very large. Some occur only under certain conditions, and they all apply only to the Monday after (daylight saving time) begins."
Clipman, who has taught courses in positive psychology and health psychology, has some theories about why people's moods seem to change for the better beyond Monday.
One involves basic chemistry, she said.
Cortisol is a hormone in the bloodstream that indicates stress and is typically present during bad moods.
In most people, cortisol levels are lowest in summer and highest in winter.
"Baseline cortisol levels vary in response to many things, but also in response to the number of hours of daylight," Clipman said. "They do not change because of (daylight saving time), but we associate (daylight saving time) with the coming late spring and summer days, when cortisol will actually be lower and we will feel better."
Also, Clipman said, people are outside in the sunlight more after daylight saving time arrives, and the sunlight entering the eye increases serotonin levels — a neurotransmitter linked to mood.
Seasonal affective disorder — winter depression — is caused by lowered serotonin levels due to lack of light, Clipman said.
Beyond science, Clipman suggests "people engage in more activities that they find joyful because of this later hour of light — shopping, exercise, etc."
"With the hour of daylight moved later in the day, there's now time to engage in feel-good activities, such as walking the dog after dinner."