SIMBAD references

Since 2011 February 27 a new differential image motion monitor (DIMM) has been operating at Roque de los Muchachos Observatory close to the Telescopio Nazionale Galileo (TNG). The purpose of this instrument is to provide useful information about the optical turbulence for astronomical observations in the neighbourhood of the TNG. We present the first statistical results from it as well as, for the first time, the relationship between the principal components analysis of local-ground atmospheric parameters and seeing. We focus on the possibility of reliable predictions concerning the future behaviour of the seeing.