Question: when does the reliable instrument record begin for climate variables
[{'answer': 'around 1850', 'provenance': [{'wikipedia_id': '182371', 'title': 'Instrumental temperature record', 'start_paragraph_id': 31, 'start_character': 156, 'end_paragraph_id': 31, 'end_character': 167, 'bleu_score': 1.0, 'section': 'Section::::Global record from 1850.\n'}]}, {'provenance': [{'wikipedia_id': '182371', 'title': 'Instrumental temperature record', 'start_paragraph_id': 31, 'start_character': 0, 'end_paragraph_id': 31, 'end_character': 255, 'bleu_score': 0.8675979125638371, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 3520022840804288438}, 'section': 'Section::::Global record from 1850.\n'}]}]