How did the Little Ice Age boost forests in Mexico?
COUNTERINTUITIVE or what? The forests of the Caribbean were at their densest for the past 2000 years during the little ice age. How could this period of cooling have led to the forests reaching a peak of growth? From 1350 to 1850 the little ice age cooled low latitudes and dried the Caribbean. So you might expect to see evidence of this dry spell in the Yucatan Peninsula, says Maria Lozano-Garcia, a palaeontologist at the National Autonomous University of Mexico. Instead, Lozano-Garcia and colleagues found that the normal dry season was shorter or nonexistent during the little ice age. This was indicated by a sharp increase in the amount of pollen from both lowland and upland forests deposited in core-samples taken from Lago Verde, a small lake about 200 metres above sea level near the southern Gulf of Mexico. Astonishingly, the lake level also rose (Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.0707896104). Lozano-Garcia suggests that an increase in winter winds,
