大家在查： Northern America natural landscape polar circle Kalaallit Nunaat South Shetland Islands brown soil Western United States downward flow 30 degrees north latitude ironical maritime air

polar maritime air mass

民航专... ... 1200 Polar Front 极面 1201 Polar Maritime Air Mass 极地海洋气团 1202 Polar Pacific Air Mass 极地太平洋气团 ...