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，城市地区的降水量可能大于周边农村;这一现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，从而使上方流经空气降速，并逐渐汇聚。
precipitation 降水（量）
due to 因为
terrain 地形
bring on 导致，引起
converge 汇聚
