Studies suggest that precipitation may be greater in cities than in the surrounding countryside; this phenomenon may be clue in part to the increased roughness of city terrain, brought on by large structures that cause surface air to slow and gradually converge.
研究表明，城市地區的降水量可能大于周邊農村;這一現象部分上是城市地形地表粗糙度的增加。由于城市大型建筑物使地表粗糙度增加，從而使上方流經空氣降速，并逐漸匯聚。
precipitation 降水（量）
due to 因為
terrain 地形
bring on 導致，引起
converge 匯聚
