Chicago Approach can coordinate a TMI with the ATCSCC and Chicago Centre, requiring that Center feed the airplanes to Approach spaced by thirty miles.
Via CDM conference calls, the ATCSCC can propose a new solution--a Ground Delay Program (GDP)--and include it in their operational plan.
The ATCSCC's software assigns those EDCTs on an equitable basis.
The ATCSCC can chop the throttle to idle and shut down traffic flow at the source.
While the ATCSCC is the focal point for all traffic management decisions, ground stops often originate at lower level facilities.
When a flight is delayed, the order to keep it grounded originated with the ATCSCC. Don't hate them.
The ATCSCC also has a significant role in responding to emergency and national security situations.
The actions taken on 9/11 were a hyperbolic example of one of the ATCSCC's tools: the Ground Delay Program (GDP), commonly referred to as a ground stop.
Sometimes the ATCSCC wants only select flights to be held on the ground.