Spring is a season full of changes that are easy to notice, from greener grass to brighter skies and busy birds. It happens because Earth is tilted as it travels around the Sun, so different places get different amounts of sunlight during the year. That extra light and warmth help plants grow and many animals become more active.
Why Spring Happens

source: facts.uk
Spring begins when a hemisphere starts leaning more toward the Sun than it did in winter. The sunlight hits that part of Earth more directly, so days usually feel warmer and longer. Around the spring equinox, day and night are close to the same length in many places, though the exact timing and weather can vary by location. Spring does not arrive on the same date everywhere, because the Northern and Southern Hemispheres have opposite seasons.
That means when one side of Earth is enjoying spring, the other side is moving into autumn. This is one of the most interesting parts of Earth’s yearly cycle.

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Signs of Spring

source: thefeather.com

source: mystart.com
People often notice spring first through the weather. Temperatures usually rise, snow may melt, and rainy days can become more common in some places. Sunlight lasts longer into the evening, which gives plants more time to grow. Trees may bud, lawns turn green again, and flowers such as tulips or daffodils bloom. These changes happen because plants respond to light, warmth, and moisture.
Spring can look different in deserts, mountains, and tropical climates, but the season still often brings a fresh burst of growth. That is why many people think of spring as a time when nature wakes up.

source: www.britannica.com

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Spring also brings exciting changes for animals. Many birds migrate back to warmer or food-rich areas, while others begin nesting. Frogs may start calling near ponds, bees become busier around flowers, and some mammals have their young in spring when food is easier to find. One surprising fact is that spring can begin with very different weather from place to place; it might feel mild in one region and still be chilly in another.
Another fun fact is that longer daylight helps both plants and animals stay active for more of the day. Those small changes make spring easy to spot and fun to learn about.

source: www.madewithhappy.com