Read the sea level isobar map of a place in the northern hemisphere and complete the following requirements. (1) The weather system that affects A is _ _ _ _ _. Under the control of this system, A.

(1) From the distribution of isobars in the figure, the weather system at A is anticyclone, and under the control of this system, the weather feature at A is sunny; The weather system is a cyclone at best. Under the control of this system, the weather at point B is characterized by rainy weather.

(2) According to the knowledge of frontal cyclone, point C is located in front of the cold front and will be affected by the cold front weather. When the cold front crosses the border, there will be strong winds, cooling and rainy weather. After the weather system transits, the temperature drops, the air pressure rises and the weather turns fine.

(3) Ground C is located in front of the cold front and behind the warm front, and is controlled by a single warm air mass.

(4) Specifically, the wind direction is from high pressure to low pressure, and the northern hemisphere deflects to the right. The wind direction at G in the figure is northwest wind.

So the answer is:

(1) cyclone prevention in sunny days and rainy days

(2)C？ Cold front? Wind cooling, rain and snow? The temperature drops, the air pressure rises, and the weather turns fine.

(3) warmth?

(4) Northwest wind