CrowdMag - crowdsourcing Earth's magnetic data

Manoj Nair(1), Nir Boneh(1) and Arnaud Chulliat (3)

Abstract
NOAA’s National Geophysical Data Center (NGDC) develops magnetic field models to aid navigation, resource exploration and scientific research. Our CrowdMag project explores whether digital magnetometers built in modern mobile phones can be used as scientific instruments to measure Earth’s magnetic field. The idea is that crowdsourced magnetic data can improve magnetic field models by filling data gaps with existing technologies that capitalize on citizen science. Most modern mobile phones have digital magnetometers to orient themselves. A key challenge to this endeavor is the low sensitivity of the phone’s magnetometer (~300 nT compared to 0.1 nT of science quality sensor). By sourcing magnetic data from a large number of users, we plan to reduce noise in the data. We released the CrowdMag apps (Android, iOS) for public participation in October, 2014. More than 4000 users currently contribute data to the project. Preliminary data analysis indicates that the crowdsourced data are generally consistent with a large scale representation of the Earth’s magnetic field. Mapping the largely unknown local distortions in the magnetic field is the next step. URL: http://www.ngdc.noaa.gov/geomag/crowdmag.shtml