In a recent article [Journal of Pacific Archaeology, vol 1(2), 2010], Scott Fitzpatrick contends that the AD 1300 event model is unhelpful as a key to understanding environmental and societal change in the Pacific during the past 1500 years. We reject this contention on the grounds that there are ample and persuasive grounds for supposing otherwise. The AD 1300 event model proposes that climate change (especially cooling) and sea-level fall affected most of the Pacific Basin during the transition between the Medieval Warm Period and Little Ice Age, and that the impacts of these changes on food resources were so profound that they led to enduring impacts on human societies in this region, particularly Pacific Islands. We aver that the AD 1300 event model remains a powerful tool for understanding last-millennium environmental and societal change in the Pacific Islands and that all the charges Fitzpatrick levels against it can be readily dismissed.

During the last millennium in the Pacific Basin (islands and continental rim) there was a marked contrast between 'times of plenty' and 'times of less' for its human societies. This contrast is attributable to climate and sea-level variations, notably the Medieval Warm Period (a.d. 700–1250) and the Little Ice Age (a.d. 1350–1800) separated by a time of rapid cooling and sea-level fall called the 'a.d. 1300 Event.' Outlines of the times of plenty during the Medieval Warm Period and the times of less during the Little Ice Age are given, supported by a number of examples. These confirm a general picture of societal collapse as a result of the a.d. 1300 Event. Well-dated human responses to the a.d. 1300 Event (establishment of fortified settlements, end of ocean voyaging) allow links to potential nonhuman causes to be strengthened. Although more data referring to both (natural) changes and their human effects are needed, a conclusion involving environmental determinism is inescapable.