Relationship between Typhoon and Subtropical High

The relationship between typhoon and subtropical high is mutually restricted and influenced.

When the subtropical high is east-west zonal and its intensity is stable, the typhoon on the south side will move westward and its path will be stable; If the intensity of the subtropical high is not strong, when the typhoon moves to the southwest, it will cause the subtropical high to move eastward, and the typhoon may also turn to the north. In addition, the typhoon can break the weak subtropical high and pass through it. So generally speaking, the relationship between typhoon and subtropical high is mutually restricted and influenced.

Subtropical high is a warm high, coupled with its prevailing downward airflow warming effect, and the basic weather pattern in the central area (called ridge line) is sunny, hot and dry, so the weather where the subtropical high is located is hot and rainy. If the subtropical high stably controls an area, it is very prone to dry and hot weather here.

Causes of subtropical high

The formation principle of subtropical high is not as complicated as we thought, and solar radiation and geostrophic deflection are the main reasons.

The solar radiation in the equatorial region is relatively strong, and the air in this region will rise, and when it reaches high altitude, it will flow in the polar direction. However, the geostrophic force keeps the airflow deviating. With the increase of latitude, the geostrophic force becomes larger, which makes the airflow in the subtropical area (near 30 degrees north latitude) basically change from west to east, which hinders the subsequent air. This obstacle causes other air above to gather and be forced to sink, thus producing a subtropical high.

Due to the differences between land and sea and topography, there are many high pressure centers in the subtropical ocean, whether in the southern hemisphere or the northern hemisphere, whether in the Pacific Ocean or the Atlantic Ocean. But among these subtropical high, the subtropical high in the northwest Pacific has the greatest influence on China.