Some embodiments of the invention pertain to generating (s10) and providing (s20) ionospheric disturbance information from navigation satellite system (NSS) reference stations or reference station system to NSS receivers or NSS receiver systems. Station-specific and/or satellite-specific ionospheric disturbance information may be obtained (s40) on the receiver side for mitigation purposes (s60, s70, s80) in the context of estimating parameters useful to determine a position. The ionospheric disturbance information may for example comprise ionospheric amplitude scintillation information, ionospheric phase scintillation information, and/or ionospheric delay gradient information. Systems, vehicles, and computer programs are also disclosed.