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What is a season? What causes the seasons? What season is the earth tipped toward the sun? What season is the earth tipped away from the sun? What are the two dates in which the angles of the sun are the most extreme? What is the equator? Why is it hotter at the equator than it is at the poles? |
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What is a season?
A season is a time of year. There are four seasons each year. The four seasons are Spring, Summer, Fall and Winter. The weather outside is different in each season. The length of the daylight hours is also different in each of season. Spring Summer Fall (Autum) Winter Spring Spring is the season after Winter and before Summer. The temperature gets warmer and plants start to grow. Leaves appear on the trees. Grass grows and turns green. Flowers come up and bloom. Fruit trees bloom. Many baby animals are born in the spring. Summer Summer is the warmest season of the year. It follows Spring and comes before Fall. Vegetables and fruits grow in summer. Summer is the season with the longest days. There is more sunlight during summer than during the other seasons. Fall (Autum) Fall is the season after Summer and before Winter. It is also called Autumn. Trees, vegetables, fruits, flowers and grass stop growing in the Fall. The leaves on trees and bushes change color and fall to the ground. The daylight hours get shorter and the days get cooler. Winter Winter is the coldest season of the year. The temperature outside is always coldest in Winter. Some places will have snow storms. The days are the shortest in winter. Trees and other plants are resting during the winter and waiting until Spring to start to grow again. Location, location, location The timing and characteristics of the seasons depends upon the location on Earth. Regions near the equator experience fairly constant temperatures throughout the year, with balmy winters barely discernable from warm summers. But for areas to the north and south, the seasons can change more significantly. People closer to the poles might experience icier, more frigid winters, while those closer to the equator might suffer hotter summers. Other factors can also affect the weather and temperature over the seasons; some areas experience dry summers as temperatures spike, while others might call summer their "wet season," experiencing higher than average rainfall. Mountainous regions might experience more snowfall than plains within the same latitude, while oceanfront property could see an increase in violent tropical storms as the weather shifts. The time of year a region experiences a season depends on whether it is in the northern or southern hemisphere. The Southern Hemisphere experiences winter while its northern neighbors chart summer; the north sees the slow blossom of spring while the south brings in the autumn harvest. Earth and the sun The cycle of seasons is caused by the Earth's tilt toward the sun. The planet rotates around an (invisible) axis. At different times during the year, the northern or southern axis is closer to the sun. During these times, the hemisphere tipped toward the star experiences summer, while the hemisphere tilted away from the sun experiences winter. At other locations in Earth's annual journey, the axis is not tilted toward the sun but instead along the planet's path, parallel to the star. During these times of the year, the hemispheres experience spring and autumn. The astronomical definition of the seasons relate to specific points in Earth's trip around the sun. The summer and winter solstice, the longest and shortest day of the year, occur when the axis of the Earth is either closest or farthest from the sun. The summer solstice in the northern hemisphere occurs around June 21, the same day as the winter solstice in the southern hemisphere. The south's summer solstice occurs around December 21, the winter solstice for the north. In both hemispheres, the summer solstice marks the first day of astronomical summer, while the winter solstice is considered the first day of astronomical winter. Equinoxes are another significant day during Earth's journey around the sun. On these days, the planet's axis is pointed parallel to the sun, rather than toward or away from it. Day and night during the equinoxes are supposed to be close to equal. The spring, or vernal, equinox for the northern hemisphere takes place around March 20, the same day as the south's autumnal equinox. The vernal equinox in the southern hemisphere occurs around September 20, when people in the north celebrate the autumnal equinox. The vernal equinox marks the first day of astronomical spring for a hemisphere, while the autumnal equinox ushers in the first day of fall. [INFOGRAPHIC: Earth's Solstices & Equinoxes Explained] But changes in the weather often precede these significant points. The meteorological seasons focus on these changes, fitting the seasons to the three months that best usher them in. December to February marks meteorological winter in the Northern Hemisphere and meteorological summer in the southern. March, April, and May are lauded as spring or autumn, depending on the location, while June through August are the months of summer for the north and winter for the south. September, October, and November conclude the cycle, ushering in fall in northern regions and spring in southern. The seasons can bring a wide variety to the year for those locations that experience them in full. The weather in each one may allow people to engage in activities that they cannot perform in others — skiing in the winter, swimming in the summer. Each season brings with it its own potential dangers, but also its own particular brand of beauty. What causes the seasons?  The seasons are caused by the tilt of the Earth's rotational axis away or toward the sun as it travels through its year-long path around the sun. The Earth has a tilt of 23.5 degrees relative to the "ecliptic plane" (the imaginary surface formed by it's almost-cicular path around the sun). The tilt toward the sun is maximized during Northern Hemisphere summer in late June (the "summer solstice"). At this time, the amount of sunlight reaching the Northern Hemisphere is at a maximum. In late December, on the date of the "winter solstice", the Earth's tilt away from the sun is maximized, leading to a minimum of sunlight reaching the Northern Hemisphere. The seasons, of course, are reversed in the Southern Hemisphere. During the winter, cold air masses build up over North America, Europe, and Asia, due to the low intensity of sunlight. The oceanic air masses are much less affected by the seasons because circulations in the upper ocean replenish warm surface water if it has been cooled. The strong temperature contrast between the cold air masses over land and the relatively warmer air masses over the ocean lead to extratropical (non-tropical) cyclone formation (low pressure). These storms are thus much more frequent and intense in the winter than in the summer. Interesting facts: The sun is actually closest to the Earth during Northern Hemisphere winter (not summer). Thus, the amount of sunlight averaged over the whole Earth, is as much as 7% more intense in the winter than the summer. Despite this fact, the global-average surface temperature is warmer in Northern Hemisphere summer, due to the much greater expanse of land there, and since land heats to a higher temperature than the ocean does. 
2. What season is the earth tipped toward the sun? Summer. 3. What season is the earth tipped away from the sun? Winter. 4. What are the two dates in which the angles of the sun are the most extreme? June 21st and Dec. 21 June 20-21 is start of summer in the Northern Hemisphere but simultaneously the start of winter in the Southern Hemisphere. It's also the longest day of sunlight for places in the Northern Hemisphere and the shortest day for south of the equator. What is the equator? The equator is an imaginary geographic line that goes around the Earth halfway between the North Pole and the South Pole. It divides the planet into the Northern and Southern hemispheres. This massive circle is 24,902 miles (40,076 kilometers) around and 7,927 miles (12,757 kilometers) in diameter. It lies 90 degrees of latitude (6,215 miles, or 10,002 kilometers) from each of the Earth's poles. Why is it hotter at the equator than it is at the poles? The earth is spherical in shape. At any point of time when the earth faces the sun, its rays are more spread out at the poles than at the equator. Also the light rays have to travel farther through the atmosphere to reach the earth's surface. The poles thus receive slant rays having less intensity of heat. On the other hand, the equator receives direct light of high heat intensity as the rays travel straight and are least spread out on the earth's surface. This is why places near the equator are hotter than those near the poles. |