TPO 10 氣候變化 - 英檢

We need therefore to know how much the climate can vary of its own accord in
order to interpret with confidence the extent to which recent changes are
natural as opposed to being the result of human activities.

can vary of its own accord
這一句要怎麼翻才算?

the extent to which recent changes are natural

結構看不太太懂 the extent to which

後面as 該翻成?

感謝回答

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