1. A system for iterative closest point registration to accurately determine a position of a vehicle in a substantially featureless environment, comprising: a memory onboard a vehicle, the memory configured at least for storing a first set of point cloud data, a persistent estimate and computer executable program code; a sensor onboard the vehicle configured for sensing a second set of point cloud data; a controller operatively coupled to the memory and the sensor, the controller configured for executing the computer readable program code, the computer readable program code comprising instructions for causing the controller to perform and direct the steps of: accessing the first set of point cloud data from the memory; receiving the second set of point cloud data from the sensor; determining a first transformation estimate via registration of the second set of point cloud data to the first set of point cloud data; determining a confidence level associated with the first transformation estimate based on an error propagation, the error propagation resulting from measurement error of the sensor; based on the confidence level associated with the first transformation estimate being below a predetermined value due to a reduced number of features accurately sensed by the sensor, determining an appropriate number of degrees of freedom to use to determine at least one second transformation estimate, the appropriate number being one of: six degrees of freedom and less than six degrees of freedom; updating the persistent estimate using the at one second transformation estimate with the appropriate number of degrees of freedom; and determining the position of the vehicle using the registered set of point cloud data according to the updated persistent estimate and the at least one second transformation estimate, the position for presentation to a display or an additional processing system of the vehicle.