Question: what is the main source of energy for wind currents on earth
[{'answer': 'differences in the atmospheric pressure', 'provenance': [{'wikipedia_id': '15440316', 'title': 'Wind', 'start_paragraph_id': 6, 'start_character': 18, 'end_paragraph_id': 6, 'end_character': 57, 'bleu_score': 1.0, 'section': 'Section::::Causes.\n'}]}, {'provenance': [{'wikipedia_id': '15440316', 'title': 'Wind', 'start_paragraph_id': 6, 'start_character': 0, 'end_paragraph_id': 6, 'end_character': 869, 'bleu_score': 0.985764216565234, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 7804767680622557571}, 'section': 'Section::::Causes.\n'}]}]