Reply on “Climate impact on the development of Pre-Classic Maya civilization” (RC-2)

Abstract

The impact of climate change on the development and disintegration of Maya civilization has long been debated. The lack of agreement among existing palaeoclimatic records from the region has prevented a detailed understanding of regional-scale climatic variability, its climatic forcing mechanisms, and its impact on the ancient Maya. We present two new palaeo-precipitation records for the Central Maya Lowlands, spanning the Pre-Classic period (1800 BCE-250 CE), a key epoch in the development of Maya civilization. Lake Tuspan's diatom record is indicative of precipitation changes at a local scale, while a beach ridge elevation record from world's largest late Holocene beach ridge plain provides a regional picture. We identify centennial-scale variability in palaeo-precipitation that significantly correlates with the North Atlantic δ 14 C atmospheric record, with a comparable periodicity of approximately 500 years, indicating an important role of North Atlantic atmospheric-oceanic forcing on precipitation in the Central Maya Lowlands. The Early Pre-Classic period was characterized by relatively dry conditions, shifting to wetter conditions during the Middle Pre-Classic period, around the well-known 850 BCE (2.8 ka) event. We propose that this wet period may have been unfavorable for agricultural intensification in the Central Maya Lowlands, explaining the relatively delayed development of Maya civilization in this area. A return to relatively drier conditions during the Late Pre-Classic period coincides with rapid agricultural intensification in the region and the establishment of major cities. 1. Introduction During the last decades, a wealth of new data has been gathered to understand human-environmental interaction and the role of climate change in the development and disintegration of societies in the Maya Lowlands (e.g.,