{'fraction_non_alphanumeric': 0.02527075812274368, 'fraction_numerical': 0.01684717208182912, 'mean_word_length': 5.028985507246377, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Origin, chronology and climatological significance of annual-moraine ridges at Myrdalsjökull, Iceland

Minor, transverse moraine ridges have formed annually at the retreating north margin of Myrdalsjökull, 550-600 m a.s.l., in south Iceland during the period 1928-1981. They are composed of slabs of clast-paved lodgement till and their formation at the glacier edge results from subglacial freezing-on of sediment slabs during winter and the annual cycle of ice-front activity. This type of annual-moraine ridge is likely to be characteristic of retreating temperate glaciers where the glacier toe is thin and winters are cold. The speed of glacier retreat is finely balanced with changes in mean summer temperature suggesting that the short-term ice-front fluctuations are climatically induced and not a result of surge activity.