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N.W. Peddie

Publications and source records attributed to N.W. Peddie.

At least 19 recordsLinked to original sources
USGS1992

Analysis of geomagnetic secular variation during 1980-1985 and 1985- 1990, and geomagnetic models proposed for the 1991 revision of the International Geomagnetic Reference Field

The secular variation of the main geomagnetic field during the periods 1980-1985 and 1985-1990 was analyzed in terms of spherical harmonics up to the eighth degree and order. Data from worldwide magnetic observatories and the Navy's Project MAGNET aerial surveys were used. The resulting pair of secular-variation models was used to update the Definitive Geomagnetic Reference Field (DGRF) model for 1980, resulting in new main-field models for 1985.0 and 1990.0. These, along with the secular-variation model for 1985-1990, were proposed for the 1991 revision of the International Geomagnetic Reference Field (IGRF).

Journal of Geomagnetism & Geoelectricity↗
USGS1992

Evaluation of models proposed for the 1991 revision of the International Geomagnetic Reference Field

The 1991 revision of the International Geomagnetic Reference Field (IGRF) comprises a definitive main-field model for 1985.0, amain-field model for 1990.0, and a forecast secular-variation model for the period 1990-1995. The five 1985.0 main-field models and five 1990.0 main-field models that were proposed have been evaluated by comparing them with one another, with magnetic observatory data, and with Project MAGNET aerial survey data. The three secular-variation models that were proposed have also been compared with one another, and with estimates of recent rates of change at the observatories. The comparisons indicate that the main-field models proposed by IZMIRAN, and the secular-variation model proposed jointly by the British Geological Survey and the U. S. Naval Oceanographic Office, should be assigned relatively lower weight in the derivation of the new IGRF models.

Journal of Geomagnetism & Geoelectricity↗