Why is the solar intensity at noon higher at the summer solstice than at the winter solstice and relationship between the angle of sunlight and seasons?
The higher solar intensity at noon during the summer solstice compared to the winter solstice is due to Earth's axial tilt and its orbit around the sun. During summer, the North Pole is tilted toward the sun, causing sunlight to travel through less atmosphere, resulting in higher concentration of solar energy. In contrast, during winter, the North Pole is tilted away from the sun, leading to sunlight traveling through more atmosphere and spreading out over a larger area, resulting in lower solar intensity. This variation is caused by the angle at which sunlight strikes the Earth's surface, which changes with the seasons.
The higher solar intensity at noon during the summer solstice compared to the winter solstice is due to Earth's axial tilt and its orbit around the sun. During summer, the North Pole is tilted toward the sun, causing sunlight to travel through fewer atmospheres, resulting in higher concentration of solar energy. The summer solstice is the longest day of the year, and the winter solstice is the shortest day of the year. The summer solstice occurs when the sun is at its highest point in the sky, and the winter solstice occurs when the sun is at its lowest point in the sky. At local midnight the summer Sun culminates at 3.44°. Said another way, it does not set; it is the polar day. Solstice day arcs as viewed from either pole (90° latitude). At the time of the summer or winter solstices, the Sun is 23.44° degrees above or below the horizon, respectively, irrespective of time of day. During the summer solstice, the Sun shines most directly on the Tropic of Cancer, 23.5 degrees north of the equator, giving its most direct energy on Earth to the Northern Hemisphere. Since the earth's axis is tilted, the sun is higher when you are on the part of the earth where the axis points more towards the sun, and lower on the part of the Earth where the axis points away from the sun. The summer solstice occurs at the moment the earth's tilt toward from the sun is at a maximum. Therefore, on the day of the summer solstice, the sun appears at its highest elevation with a noontime position that changes very little for several days before and after the summer solstice. During winter, the Northern Hemisphere leans away from the sun, there are fewer daylight hours, and the sun hits us at an angle; this makes it appear lower in the sky. There is less heating because the angled sun's rays are “spread out” rather than direct. The Sun appears higher in the sky during the northern hemisphere summer, moving lower as we move into winter. The larger loop shows how the Sun's position changes rapidly between measurements. At that time of year the Earth is closer to the Sun and therefore travels faster around it. As the tilt of the Earth changes relative to the Sun, the seasons change. On the winter solstice the angle of the Sun is lowest on the horizon, shining at you more than on you. This is why it casts a longer shadow in winter. This is why the Earth's 23.5 degree tilt is all important in changing our seasons. Near June 21st, the summer solstice, the Earth is tilted such that the Sun is positioned directly over the Tropic of Cancer at 23.5 degrees north latitude. This situates the northern hemisphere in a more direct path of the Sun's energy. Earth's tilted axis causes the seasons. Throughout the year, different parts of Earth receive the Sun's most direct rays. So, when the North Pole tilts toward the Sun, it's summer in the Northern Hemisphere. And when the South Pole tilts toward the Sun, its winter in the Northern Hemisphere. When the sun's rays strike Earth's surface near the equator, the incoming solar radiation is more direct (nearly perpendicular or closer to a 90˚ angle). Therefore, the solar radiation is concentrated over a smaller surface area, causing warmer temperatures.
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