Extra を

Hi guys,
I was wondering if the first を is a typo in this news article. Should it be に？
海や川が凍って、海を流れてくる氷りを「流氷」といい ます。北海道には、冬になるとロシアから流氷が来きま す。

My interpretation is.....
Frozen Oceans and rivers which start to flow at sea as ice is called drift ice. As for Hokkaido, it becomes winter when drift ice from Russia comes.

よろしくお願いします

を indicates 通過 not 始点 in this case. Also 冬になると means more like 'when it's winter'.

Yeah, it's not a typo. (Although there are typos in the quote "氷りを and 来きます" probably you made.) As Morphling-san pointed out, を indicates the location of transfer in that sentence, as same as 道を歩く, 坂を上る or 空を飛ぶ. 海に流れてくる氷 means "ice that flows into the sea (mostly floating down a river)", weareas 海を流れてくる氷 is "ice that drifts on the sea (to our side)".

Your translation "it becomes winter when drift ice from Russia comes" means ロシアから流氷が来ると、冬になります. The conditional clause is 冬になると, not ロシアから流氷が来きます.

北海道に shows that 北海道 is the destination. The usual word order is 流氷が北海道に流れてきます. は is used to topicaize it.

The を particle is a very interesting and versatile one. Thanks all.