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We propose a simple method for the reduction of noise in vertical seismic recordings at frequencies below 2 mHz. The method consists in subtracting the locally recorded, scaled, atmospheric pressure signal from the gravity record. The scale factor is frequency independent and can be linearly estimated from the data. While such a pressure correction was previously only used in the analysis of tidal records, it is equally efficient at the low‐frequency end of the normal mode band and we use gravity recordings of the big 1994 Shikotan and Bolivian quakes to demonstrate this point. Our examples also show that this correction permits to achieve noise levels well below the New Low Noise Model (NLNM) [Peterson, 1993]. The success of the correction also sheds some light on the physical processes responsible for the generation of low‐frequency seismic noise at quiet observatories.

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This letter discusses an alternative storage approach to conventional magnetic data storage. The approach uses a 32ϫ32 array of scanning probe microscopes working in parallel to read and write data as small indentations in a polymer storage medium. The results have densities of 100-200 Gbit/in. 2. At such densities, it is shown that well over half the array works, and at lower densities more than 80% of levers are working.