It’s finally here. Welcome to summer!
Summer arrived today, June 21, at 12:24 am EDT. The summer solstice officially marks the start of the summer season.
It’s the day when those of us living in the northern hemisphere will experience the most daylight of the calendar year. Around New York Harbor the longest day of the year is over 15 hours of sunlight.
At noon today, the Sun will also be located at the highest point in the sky around New York Harbor at about 73 degrees 30 minutes above the horizon. That is as high as the Sun will ever get around New York Harbor. The Sun has been getting higher and higher in the sky ever since the winter solstice back in December and through the spring vernal equinox in March.
The Sun will produce its maximum solar input to the atmosphere in June, but it does not exert its greatest influence on surface temperatures until July and August. This is when the cumulative effect of the sun’s heating peaks.
The summer solstice is not caused by the Earth being closer to the sun (as some people incorrectly believe), but by the orbit of Earth and its angle of orientation as it rotates around the Sun. The Earth is tilted on an axis at about 23.44 degrees. When the northern hemisphere is tilted toward the Sun, the days are longer and the sun is high in the sky.
At this same time, the southern half of the Earth is tilted away from the Sun now. People living in southern Argentina are getting ready for winter. Six months later, the northern hemisphere will be tilted away from the sun and the days are shorter and the sun is low in the sky, and we will have winter.
The seasons are based on the Earth’s journey around the Sun, with the four quarters of the orbit determining the four seasons: winter, spring, summer, and autumn.
Get outside and enjoy the summer weather. It will not last long. The astronomical summer will end on September 22.