The findings dramatically alter the climatic framework used by geologists reconstructing past climate change; archaeologists describing human responses to environmental change; and water managers tasked with balancing environmental, agricultural and urban water needs in drought-stressed southwestern North America.
The number of endangered Mexican gray wolves confirmed in the wild declined for the third successive year as a result of trapping and shooting by the U.S. government.
Cultural changes during this period, including the earliest evidence for cultivation of corn and cotton, occur concurrently with changes in available moisture.
The Colorado River basin is home to more than 40 dams and diversions and functions more as a system of regulated canals and reservoirs than a river.
Scientists and managers in the Sierra Nevada parks have long recognized the essential nature of fire in these forests and have responded over the years with an increasingly sophisticated fire restoration program using both prescribed burns and natural fires.