National Geophysical Data CenterThis line shapefile shows lines of equal horizontal intensity of the Earth's magnetic field, derived from the International Geomagnetic Reference Field (IGRF) for the epoch 2010.0. Magnetic intensity is the strength of the magnetic field, and is described in terms of a horizontal component and a vertical component. Horizontal intensity is the horizontal strength of the magnetic field. This layer is part of the 1997-2014 edition of the National Atlas of the United States.These data are intended for geographic display and analysis at the national level, and for large regional areas. The data should be displayed and analyzed at scales appropriate for 1:2,000,000-scale data. No responsibility is assumed by the U.S. Geological Survey in the use of these data.This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.Shapefilehttps://purl.stanford.edu/nm647kh2178engNational Atlas of the United StatesPublicGeomagnetismGeoscientific InformationMagnetic Field - Horizontal Component of the Total Field Intensity for the Epoch 2010.0DatasetsUnited StatesAlaskaAlabamaArizonaArkansasColoradoConnecticutDelawareFloridaGeorgiaHawaiiIdahoIllinoisIndianaIowaKansasKentuckyLouisianaMaineMarylandMassachusettsMichiganMinnesotaMississippiMissouriMontanaNebraskaNevadaNew HampshireNew JerseyNew MexicoNew York (State)North CarolinaNorth DakotaOhioOklahomaOregonPennsylvaniaRhode IslandSouth CarolinaSouth DakotaTennesseeTexasUtahVermontVirginiaWashington (D.C.)Washington (State)West VirginiaWisconsinWyomingNorth AmericaCubaCanadaMexicoPuerto RicoUnited States Virgin Islands2010Stanford