What does "competing for summer" mean?

Is it "competing for summer" to hang the extremely hot weather warning for two or three days in a row? Not really, because it's still a hot summer, and we haven't arrived in beginning of autumn yet. "Autumn competes for summer" is to describe the weather in beginning of autumn and midsummer. What is the cause of the climate phenomenon of "autumn competing for summer"? The solar terms in the lunar calendar are different from the general moon cycle. In fact, the 24 solar terms belong to the solar cycle, which accurately represents the key days of temperature change in a year and provides the best basis for people to live and farm regularly in a year. From the vernal equinox, the sun gradually moved from the equator to the northern hemisphere, and the sunshine time in the northern hemisphere became longer and longer, and the days became longer and the nights became shorter. Until the summer solstice, the sun shines directly on the tropic of cancer, which is the longest day and the shortest night in a year. Then, the sun turned to the south. When it reached the equator, it was already the autumnal equinox, and the midpoint of this journey was beginning of autumn. Since the sun shines in the northern hemisphere for a long time from the vernal equinox to the summer solstice, the temperature in the northern hemisphere continues to rise and the weather changes from warm to hot summer. The solstice in summer is when the sun shines directly on the polar regions, and the cold air in the polar regions cannot go south. Therefore, when the sun turns around and shines repeatedly, the temperature rises even more, so there will be slight summer heat and great summer heat after the summer solstice, and the hot weather will last until this month. Beginning of autumn just enters autumn, because the sun is gradually moving away from the polar regions, and cold air has a chance to be active. However, after beginning of autumn, it was still hot in summer, but the sun didn't really leave the northern hemisphere. The heat of the sun and the warm atmospheric circulation will still bring high temperature weather, and the afterglow is still there. Therefore, during the period between beginning of autumn and the hot summer, the weather is sometimes unusually hot, and sometimes it feels cool and autumn. "Fighting for summer heat" describes the transition period between summer and autumn. 2011-08-09 05: 23: 48 Supplement: Please allow me to add that in summer, the sunshine time is long, and the land absorbs heat and heats up quickly, which is easy to form a low-pressure area, and the seawater absorbs heat and heats up slower than the land, forming a high-pressure area, so the wind in summer is mostly blowing from the ocean to the land, and this season is a warm and humid southwest monsoon. Stepping into beginning of autumn, the front of the northeast monsoon began to pass through China and Hong Kong in the form of trough of low pressure, but at this time, China and Hong Kong are still not dominated by the northeast monsoon, and there are still opportunities for hot weather, especially when the subtropical high extends westward, bringing sunny and partly cloudy weather, or tropical cyclones move closer to the south China coast, and China and Hong Kong are affected by downward flow, resulting in hot weather. If the vernal equinox is regarded as the sunrise in the morning, the solstice in summer is equal to noon, and the autumnal equinox is equal to sunset, "autumn fighting for summer heat" is "westward setting", it will still be quite hot, but it won't be long before the sun turns into salted egg yolk and falls to the horizon.

Reference: Old Works ── Le Yuanye's Old Works