英文句子temperatures could rise as much as 3.5 to 7.4 Celsius

严格来讲，这是个病句。理由如下：rise是不及物动词，后不能直接跟宾语。有两个方法解决此问题。
1.rise后加by，变为：Temperatures could rise by as much as 3.5 to 7.4 Celsius，“升高。。。度”

2.rise后加to,变为：Temperatures could rise to as much as 3.5 to 7.4 Celsius “升高到。。。度”

as much as是 3.5 to 7.4 Celsius的同位语，可译成“可达。。。”

这句话的意思是 温度可上升3.5到7.4摄氏度

多达（as much as)3.5到7.4度，表示升温的幅度大。