3-45. During summer in the Northern Hemisphere, where would you most likely find the Arctic front? 1. In the North Atlantic 2. In the North Pacific 3. North of Europe 4. Northeastern Asia 3-46. Which of the following statements concerning polar fronts is correct? 1. They  separate  polar  air  from  tropical  air only 2. They are stronger in summer than winter 3. They   are   more   common   along   eastern coasts of continents in summer 4. They are present throughout the year 3-47. What  three  elements  are  used  to  determine whether or not a front actually exists? 1. Visibility, temperature, and pressure 2. Clouds, temperature, and wind 3. Temperature, pressure, and wind 4. Present weather, temperature, and pressure 3-48. The   temperature   increase   within   a   frontal inversion  and  the  thickness  of  the  inversion layer provide a rough indication of 1. frontal slope 2. frontal intensity 3. turbulent mixing 4. precipitation within a frontal zone 3-49. Which of the following statements concerning frontal inversions is correct? 1. Cold fronts generally show stronger inversions than warm fronts 2. They normally show up as a decrease in the lapse rate below 400 millibars 3. Double  inversions  are  often  evident  with occluded fronts 4. Each of the above 3-50. Which  of  the  following  occurrences  causes  a front  to  exhibit  a  strong  inversion  layer  and little or no weather activity? 1. Subsidence   in   the   warm   air   above   the frontal surface 2. Subsidence   in   the   cold   air   beneath   the frontal surface 3. Adiabatic warming of the cold air beneath the frontal surface 4. Upward vertical motion in the warm air 3-51. In   the   Northern   Hemisphere   when   a   front passes your station, what change takes place in the wind direction? 1. It veers 2. It backs 3. It shifts in a counterclockwise direction 4. It shifts in a clockwise direction 3-52. In  a  frontal  zone,  what,  if  anything,  normally happens to the wind speeds? 1. They increase with height only 2. They decrease with height only 3. They may increase or decrease with height 4. They  vary  on  either  side  of  the  frontal zone,  but  maintain  a  steady  state  through the zone 3-53. At the surface, when a front moves beyond its associated  pressure  trough,  how,  if  at  all,  are the winds across the front affected? 1. The  wind  speeds  do  not  change,  but  the wind shift becomes far more apparent 2. The  wind  speeds  show  a  drastic  change, and   the   wind   shift   becomes   far   more apparent 3. The wind speed difference across the front continues,  but  the  wind  shift  can  become almost undetectable 4. Movement   out   of   the   pressure   trough affects neither wind speeds or direction 3-54. Which  of  the  following  factors  causes  frontal clouds, condensation, and weather? 1. Low pressure 2. Friction between front and Earth’s surface 3. Vertical displacement of air along the front 4. Each of the above 3-55. Which   of   the   following   frontal   slopes   is classified as being the steepest? 1. 1:35 2. 1:50 3. 1:150 4. 1:300 3-56. What  factor(s)  contribute(s)  to  a  steep  frontal slope? 1. High  wind  velocity  difference  across  the front 2. Small temperature contrast across the front 3. High latitude 4. All of the above 17