|MadSci Network: Environment & Ecology|
Although I do not have specific information on Poland's ice storm, it is safe to say that the 'greenhouse effect' was not the direct cause. The 'greenhouse effect' could, however, cause 'global warming', which may (or may not) change the duration and severity of storms and droughts.
The topic of 'global warming' is strongly debated and not all scientists can agree. Although data indicates that the Earth's climate is warming, the cause is not known. It could be a result of the 'greenhouse effect' or just part of a longer temperature cycle which occurs naturally.
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