【練習(xí)】

Changes in climate that had already taken place are manifested __1

from the decrease in extent and thickness of Arctic sea ice, perma- __2

frost thawing, coastal erosion, changes in ice sheets and ice　shelves, altered distribution and abundance of species. __3

Nowadays snows melt earlier in the springtime. Lakes, rivers　and bogs freeze much more later in the autumn. Reindeer herding __4

becomes more difficult so the ice is weak and may give way. __5

Nowadays winters are much colder than they used to be. __6

Occasionally during winter time it rains. We never expected this;we could not be ready for this. It is very strange. The cycle of the　yearly calendar has been disturbed greatly.Warming over northern land areas has been very greater than elsewhere in the world. The __7

changes are due to human modification of the concentration of greenhouse gases during the 20th century, leading quite directly to the projections the Artic will warm by several times as much during the __8

21st century as it did during the 20th century. The amplified warming in Arctic, in turn, directly contributes to overall global warming, as __9

well as cause changes that create impacts over the rest of the globe. __10

（責(zé)任編輯：liushengbao）