why do the northern and southern hemispheres have opposite seasons
Throughout the course of the, most places on Earth goes through four noticeable
: summer, autumn (fall), winter and spring, each lasting for about 3 months. The seasons experienced by the northern and southern hemisphere always differ by six months when it is summer in the northern hemisphere, it is winter in the southern hemisphere, and so on. Seasons are a direct consequence of the Earth s tilted rotation, which makes an of about 23. 5 degrees to a line drawn perpendicular to the plane of the. The direction of the Earth s axis stays nearly fixed throughout one, so that at different parts of the orbit one hemisphere leans towards the (summer), while the other leans away (winter). Six months later, the Earth is leaning in the opposite direction. For locations north or south of the, the main feature accompanying each season is a change in temperature caused by the varying amount of sunlight that falls on each hemisphere of the Earth throughout its annual orbit. The hemisphere tilted towards the Sun will experience longer hours of sunlight, and more direct sunlight. As the Sun is higher in the sky during summer, the sunlight reaching the surface is more concentrated. In winter, the Sun is lower in the sky, and sunlight is spread out over a larger.
During spring and autumn, both hemispheres receive about the same amount of sunlight. At the equator, the temperature variation is much smaller throughout the year, and it is common to consider just two seasons: dry and wet (or monsoon). For observers right at the north pole and the south pole, there are only two seasons an almost six-month long winter night followed by an almost six-month long summer! Within the and the (latitudes 66. 5 degrees north and south), there will be at least one polar day (24 hours of continuous daylight, sometime called the midnight sun ) and one polar night (24 continuous hours of darkness). The date of the start of the seasons is often chosen to start on the dates of the solstices (summer and winter) and equinoxes (autumn and spring). Alternatively, the start of a new season may be associated with the first day of the month (December, March, June and September) in which a or equinox occurs. The Earth s changing from the Sun due to the Earth s orbit is sometimes thought to cause the seasons. This is incorrect! The Earth s distance from the Sun varies by about 3% from closest ( distance = 147. 09 million km) to furthest approach ( distance = 152. 10 million km). This small change in distance cannot account for the temperature differences between summer and winter, and cannot explain how it can be winter in one hemisphere and summer in the other hemisphere.
Four seasons -- autumn, winter, spring and summer -- occur throughout the year. Each hemisphere experiences an opposite season. For example, the winter season in the northern hemisphere is summer in the southern hemisphere. The seasons are caused by the tilt of the Earth's axis as it orbits the sun. The Earth spins counterclockwise on its axis at an angle of 23. 4 degrees. This spinning of the Earth causes day and night because only half the world faces the sun. Moreover, as the Earth spins on its axis, it orbits the sun, taking 365 days to complete a whole orbit. Because of the tilt of the Earth's axis, different areas receive different amounts of sunlight during the Earth's orbit, creating the four seasons. The timing of the seasons is opposite for each hemisphere. This is because when the north pole is tilted toward the sun, the northern hemisphere faces the sun at a greater angle than the southern hemisphere. Therefore the northern hemisphere gets warmer. This represents the summer months for the northern hemisphere and winter for the southern hemisphere. As the Earth continues its orbit, the south pole eventually is tilted toward the sun, reversing the seasons in each hemisphere.
During the winter solstice, the sun is at its lowest path in the sky, resulting in the shortest day of the year. After this day, the sun follows a higher and higher path through the sky. The spring equinox occurs when sun rises exactly in the east and travels through the sky for 12 hours, setting exactly in the west. There is a spring and autumn equinox, where every place on Earth experiences an approximate 12-hour day. After the spring equinox, the sun continues to follow a higher and higher path through the sky until the summer solstice, the longest day of the year and the sun's highest point in the sky. After this, the sun follows a lower and lower path until it reaches the autumn equinox and then the winter solstice. Summer is the season with the longest days and warmest temperatures, with winter being the opposite. Spring represents the time when the days start to get longer, with more hours of sunlight. Autumn is the period when the days get shorter, with less sunlight, building toward the winter months. Less distinction between the seasons exists at the equator than at the poles because the equator is tilted at almost the same angle from the sun all year long.
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