What was done
The authors "studied a 5.1-m sediment core from Aguada X'caamal, a small sinkhole lake in northwest Yucatan, Mexico."

What was learned
Hodell et al.'s work revealed that "an important hydrologic change occurred in Aguada X'caamal during the 15th century AD as documented by the appearance of A. beccarii in the sediment profile, a decline in the abundance of charophytes, and an increase in the δ¹⁸O of gastropods and ostracods."  They also note that "the salinity and ¹⁸O content of the lake water increased as a result of reduced precipitation and/or increased evaporation in the mid- to late 1500s."

The seven scientists say these several changes, as well as many others they cite, "were part of a larger pattern of oceanic and atmospheric change associated with the Little Ice Age that included cooling throughout the subtropical gyre (Lund and Curry, 2004)."  Their assessment of the situation is that that "climate became drier on the Yucatan Peninsula in the 15th century AD near the onset of the Little Ice Age," and they report that "comparison of results from the Yucatan Peninsula with other circum-Caribbean paleoclimate records indicates a coherent climate response for this region."  In addition, they state that "Maya and Aztec chronicles contain references to cold, drought and famine in the period AD 1441-1460."

What it means
In contrast to climate-alarmist claims that the Little Ice Age was a regional phenomenon restricted to countries bordering the North Atlantic Ocean, the results of this study, along with those of the many corroborating studies its authors cite, tell a very different story.

Reference
Lund, D.C. and Curry, W.B.  2004.  Late Holocene variability in Florida Current surface density: patterns and possible causes.  Paleoceanography 19: 10.1029/2004PA001008.