In many volcanoes the lava bubbles quietly, tossing lava into the air at times, giving off gases, and, in general, being fairly harmless.

许多火山的熔岩静静地在冒泡，有时喷入空中，释放出气体，一般是完全无害的。

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The report blames industrial pollution from the 19th century for climate change from the mid-20th century, although the recent warming trend set in about 20 years ago from the cumulative use of fossil fuels giving off clear greenhouse gases such as methane and carbon dioxide.

CNN: Alpine resorts feel the heat