Among older people, dehydration is one of the most common hazards of hot, humid weather. See what you can save with the AARP Auto Buying Program. Recent studies have found that even mild dehydration comes with big consequences â from altered mood and impaired memory to headaches and constipation.
diurnal - of or belonging to or active during the day; diurnal animals are active during the day; diurnal flowers are open during the day and closed at night; diurnal and nocturnal offices. 2. diurnal - having a daily cycle or occurring every day; diurnal rotation of the heavens.
A day is a unit of time. In common usage, it is an interval equal to 24 hours. It also can mean the consecutive period of time during which the Sun is above the horizon, also known as daytime. The period of time during which the Earth completes one rotation with respect to the Sun is called a solar day.his phenomenon is due to tides raised by the Moon which slow Earth's rotation. Because of the way the second is defined, the mean length of a day is now about 86 400.002 seconds, and is increasing by about 1.7 milliseconds per century (an average over the last 2 700 years).