The following figure shows the ground weather map of an area on April 6, 2006 17, and the real-time distribution map of some meteorological disasters caused by the graphic weather system is within the

The following figure shows the ground weather map of an area on April 6, 2006 17, and the real-time distribution map of some meteorological disasters caused by the graphic weather system is within the dashed line. earlier times

(1) southwest and southeast have high air pressure, high air pressure center, sparse isobar and small air pressure gradient; The air pressure in the north of the central part is low, the air pressure center is low, the isobars are dense, and the air pressure gradient is large.

(2) Sandstorm.

Weather conditions: rising temperature leads to thawing of topsoil, enhanced evaporation, dry surface and abundant sand sources; The warm air mass in front of the cold front is dry, so it is difficult to form precipitation, and the cyclone is strong, and the airflow rises, forming sand blowing; The west wind is strong, forming a large-scale sandstorm.

(1) It is the key to solve the problem to determine the position of high and low pressure centers according to the isobar diagram. According to the map, the high pressure center is located in the southwest and southeast of the area, and the low pressure center is located in the north of the middle of the area. The weather conditions of sandstorm formation are answered from the aspects of fast cold front, low air humidity on one side of heating mass, rising temperature and enhanced air convection.

(2) The key information such as "April, thaw and dryness" in the title is extracted, and combined with the map information such as cold front crossing in the weather map, it is inferred that the meteorological disaster is a sandstorm.

Taking the regional weather map as the information carrier, this topic comprehensively examines the interpretation of isobar map, the judgment of meteorological disasters and the analysis of weather factors, and examines the ability of candidates to extract geographical information and solve problems by using geographical knowledge.