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Stratigraphy, geochemistry and radiocarbon dating of a succession of sediment in the Santiaguillo Basin (central-northern Mexico) help reconstruct the millennial-scale dynamics of hydrological variability that occurred in the southern part of western subtropical North America since the late last glacial. Runoff was generally above average during the late last glacial from ~ 27 to 18 ka. Following this interval, runoff decreased and deposition of authigenic carbonate and aeolian transported sediment increased until ~ 4 ka. Heinrich 1 and 2, and Younger Dryas were intervals of reduced runoff and increased aeolian activity. The wetter climate of central-northern Mexico and arid conditions in north–northwestern Mexico during the late last glacial were probably related to formation of tropical cyclones in the eastern North Pacific during the autumn with restricted rainfall swaths and an absent/weaker North American Monsoon. Enhanced North American Monsoon and tropical cyclones with expanded rainfall swaths brought more summer and autumn precipitation to a broader region extending from the central-northern Mexico to the continental interiors of southwestern US during the early Holocene.

A new geochemical record from the paaleolake Santiaguillo documents the hydrological variability of subtropical northern Mexico over the last ∼14 cal. ka. Summer-season runoff, lake water salinity and deposition of sediments by aeolian activity were reconstructed from concentrations of K, Ca and Zr/K in bulk sediments. More-than-average runoff during c. 12.3-9.3 cal. ka BP represented an interval of enhanced summer precipitation. Arid intervals of c. 14-12.3 cal. ka BP and c. 6-4.3 cal. ka BP were characterized by average and more-thanaverage aeolian activity. Comparison with proxy records of summer as well as winter precipitation from tropical and sub-tropical North America and sea surface temperatures from the Atlantic and Pacific provides insight into the source of moisture and possible forcing. The wet Pleistocene−Holocene transition and early Holocene was contemporary with warmer conditions in the Gulf of California. We suggest that the Atlantic had minimal influence on the summer precipitation of the western part of sub-tropical northern Mexico and that the source of moisture was dominantly Pacific.

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Palaeoclimate research in subtropical arid Mexico is mainly focused to infer dynamics and geographic distributions of different precipitation regimes, but droughts have received less attention. We present a new sedimentary core record indicating orbital‐scale dynamics of droughts that occurred in central‐northern Mexico during the late Quaternary. This record is reconstructed from abundances of authigenic carbonate and windblown clastic sediments in a 1026‐cm‐long sediment core from the Santiaguillo ephemeral lake. The Marine Isotope Stage (MIS) 2 lacked drought, and at least two different droughts were centred at c. 13.5 ka and at c. 7 ka during the MIS 1. The drought of c. 13.5 ka in the Santiaguillo ephemeral lake was contemporary to an interval of droughts in the Basin of Mexico (central Mexico) and stronger aeolian activity in the Baja California peninsula (northwestern Mexico). This synchronous arid condition, observed in the subtropical as well as tropical Mexico, occurred during an interval of higher spring insolation, relatively warmer but fluctuating global temperature, and stronger El Niño‐Southern Oscillation. Unsuccessful radiocarbon dating for the lower part of the sediment core led to an assignment of uncertain chronology to droughts that occurred possibly between MIS 5 and MIS 3. Copyright © 2017 John Wiley & Sons, Ltd.