What are the main characteristics of subtropics?

Tropical climate is controlled by subtropical high, so it appears in the zone controlled by subtropical high. For most of the year, due to the trade winds, it flows downwards. Its characteristics are high ground temperature, strong sunshine and dry climate. In Africa, Australia, Arabia and other tropical areas where deserts are widely distributed, they are all within the scope of the subtropical high zone. In these areas, the overall climate is very dry and there is little rain. Only on the east coast of the mainland, because there are warm ocean currents passing by and facing the trade winds, the climate will become humid. On the west coast of the mainland, due to the leeward position of the trade winds and the influence of cold ocean currents, the desert distribution can reach the coast directly.

The annual and daily changes of temperature are the remarkable characteristics of subtropical climate. At latitude 20, the annual average temperature difference is only 6.2℃, but it will reach 15℃ in the subtropical zone. The daily temperature difference is larger, reaching above 20 ~ 30℃, and the highest temperature difference can reach above 48 ~ 55℃ in summer, and it is cooler at night. Due to the dry climate and strong sunshine, some exposed sand and stones are very hot, and sometimes even eggs can be boiled. In these areas, sometimes you will see some wonders, because the air near the surface layer is heated and its density is reduced, while the air in the upper layer is denser. Therefore, the space layers with different heating degrees will refract and form a mirage. Subtropical rainfall is less and the distribution is extremely uneven. In some monsoon climate areas, the rainfall can reach more than 1000 mm, while in some desert areas, the rainfall is often less than 50 mm. Because of the low temperature, clear and stable weather and little momentum, it has become the region with the least cloud cover in the world. In general, the sky is blue and there are no clouds in Wan Li, but sometimes the sky becomes dark because of the diffuse dust.