A.upper front aloft B.cyclone C.occluded front D.cold front
单项选择题A sea breeze is a wind().
A.that blows towards the sea at night B.that blows towards an island during the day C.caused by cold air descending a coastal incline D.caused by the distant approach of a hurricane
单项选择题A line of clouds,sharp changes in wind direction,and squalls are most frequently associated with a(n)().
A.occluded front B.warm front C.cold front D.warm sector
单项选择题A hygrometer is a device used for determining().
A.the absolute temperature B.atmospheric pressure C.wind velocity D.relative humidity
单项选择题A generally circular low pressure area is called a(n)().
A.cyclone B.anticyclone C.cold front D.occluded front
单项选择题A frontal thunderstorm is caused by().
A.pronounced local heating B.wind being pushed up a mountain C.a warm air mass rising over a cold air mass D.an increased lapse rate caused by advection of warm surface air