Reduction to the pole (RTP) is a standard part of magnetic data processing method, especially for large‐scale mapping. RTP operation can transform a magnetic anomaly caused by an arbitrary source into the anomaly that the same source would produce if it is located at the pole and magnetized by induction only. Interpretation of magnetic data can further be helped by RTP in order to remove the influence of magnetic latitude on the anomalies, which is significant for anomalies caused by crust. The solution of RTP in the wave number domain faces a long standing difficulty of instability when the observed data are acquired at low latitudes especially at the geomagnetic equator. We present a new solution to this problem that allows stable reconstruction of the RTP field with a high fidelity at the magnetic equator, combining the reduction to the equator (RTE) and the phase reversal interpretation method for ∆T anomalies at low latitudes. The operation with RTE can transform theoretical magnetic anomalies located at the pole and magnetized by induction only into the observed magnetic anomalies. RTE used in our RTP procedure named SRTE is an absolutely stable potential field transformation. The principle of method is very simple, it can transform the observed magnetic anomaly at geomagnetic equator into the anomaly that would have been measured if the magnetization and ambient field were both vertical. It is a stable RTP operation at geomagnetic equator and performs a high computation speed with a reasonable accuracy. Theoretical models and the practical magnetic field data located at the magnetic equator show that the operator of RTP solution is stable and accurate.

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In recent years, the Arctic has become a hot spot for microbial research. However, fungal diversity in the Chukchi Sea (adjacent to the Arctic Ocean) is little known. The purpose of this study was to explore fungal diversity in sediments of the Chukchi Sea and the temperature adaptability of the cultured fungi. A total of 74 fungal strains were isolated from nine marine sediment samples collected from the Chukchi Sea. These fungi were identified based on morphological characteristics and sequence comparison of the internal transcribed spacers of the ribosomal DNA (ITS-rDNA) with the GenBank reference sequence database. Amongst these fungi, 61 strains belonged to the Ascomycota and 13 strains were affiliated with the Basidiomycota. The dominant genus was Penicillium. These fungal strains were cultured at 4°C, 10°C, and 25°C to determine their temperature adaptability. Most strains were able to grow at 4°C, and Thelebolus ellipsoideus was identified as a psychrophilic fungus. Our results revealed a high fungal diversity in marine sediments of the Chukchi Sea and found that some fungal species (Penicillium chrysogenum, Eutypella scoparia, Alternaria alternata, Cladosporium tenuissimum, C. perangustums and Thelebolus ellipsoideus) isolated from these sediments were able to grow at 10°C and 4°C.

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