An arrangement comprising: - at least one first external positioning system , - at least one normalized surface condition monitoring system configured to measure values of dry references, wherein the at least one normalized surface condition monitoring system is further configured to receive position information from the at least one external positioning system in order to associate the measured values of the dry references with the obtained position information, and wherein the at least one normalized surface condition monitoring system is even further configured to wirelessly transmit the measured values of the dry references associated with the position information to a node , - an apparatus comprising: ∘ a normalized surface condition monitoring sensor , ∘ a receiver configured to wirelessly receive the values of the dry references associated with the position information from the node , and ∘ a processing unit comprising at least one processing core , at least one memory including computer program code, the at least one memory and the computer program code being configured to, with the at least one processing core , cause the apparatus at least to: process the values of the dry references associated with the position information based on a real time position of the apparatus to obtain calibration of the surface condition monitoring sensor . - at least one first external positioning system , - at least one normalized surface condition monitoring system configured to measure values of dry references, wherein the at least one normalized surface condition monitoring system is further configured to receive position information from the at least one external positioning system in order to associate the measured values of the dry references with the obtained position information, and wherein the at least one normalized surface condition monitoring system is even further configured to wirelessly transmit the measured values of the dry references associated with the position information to a node , - an apparatus comprising: ∘ a normalized surface condition monitoring sensor , ∘ a receiver configured to wirelessly receive the values of the dry references associated with the position information from the node , and ∘ a processing unit comprising at least one processing core , at least one memory including computer program code, the at least one memory and the computer program code being configured to, with the at least one processing core , cause the apparatus at least to: process the values of the dry references associated with the position information based on a real time position of the apparatus to obtain calibration of the surface condition monitoring sensor . ∘ a normalized surface condition monitoring sensor , ∘ a receiver configured to wirelessly receive the values of the dry references associated with the position information from the node , and ∘ a processing unit comprising at least one processing core , at least one memory including computer program code, the at least one memory and the computer program code being configured to, with the at least one processing core , cause the apparatus at least to: process the values of the dry references associated with the position information based on a real time position of the apparatus to obtain calibration of the surface condition monitoring sensor . <EOS>