HOLOCENE CLIMATE CHANGE IN THE NORTHERN CHIHUAHUAN DESERT

Analyses of pollen, algae, and charcoal from the Diamond Y cienega, Pecos County, Texas, provide a 7,000-year history of vegetation and climate change in the northern Chihuahuan Desert. The late early-Holocene was characterized by cooler, wetter conditions and a mixed-grass prairie vegetation type. By the mid-Holocene altithermal, seasonality of precipitation shifted, annual precipitation rates dropped, and average temperatures increased resulting in a long, dry period. The late-Holocene was marked by fluctuating conditions with a general trend towards modern values. Human responses to these changes in vegetation and climate will be discussed.