What happend to Maya cities in the 900?

By the late 900s, many Maya cities in the southern lowlands experienced significant decline, often attributed to a combination of factors such as prolonged drought, environmental degradation, warfare, and social upheaval. These pressures led to the abandonment of major urban centers like Tikal and Copán, resulting in a demographic shift as populations moved northward to the more stable regions in the Yucatán Peninsula. While the southern cities fell into decline, the Maya civilization continued to thrive in other areas, adapting to new circumstances.