NOAA has announced that Monarch Magnetics will produce HDGM and HDGM-RT going forward. Explore HDGM2027
Monarch Magnetics

Monarch Magnetics

Operational geomagnetic intelligence.

Monarch Magnetics provides high-accuracy magnetic-field models, regional corrections, and time-varying information for directional drilling and other operations where magnetic-field accuracy matters.

Explore HDGM2027 See the geomagnetic stack

HDGM continuity

HDGM continues with Monarch.

Monarch Magnetics will provide HDGM going forward under a license from the University of Colorado. HDGM2027 will be Monarch's first annual release. Current users remain supported by NOAA through the end of 2026.

For HDGM-RT users, HDGM2027 + SWC-Global carries forward HDGM-RT's global time-varying external-field functionality.

The scientific leadership behind HDGM continues at Monarch: co-founders Arnaud Chulliat and Manoj C. Nair have led the development of HDGM for more than a decade and will continue its scientific development at Monarch.

Explore HDGM2027

The operational geomagnetic stack

A more complete picture of the magnetic field.

Accurate magnetic surveying depends on more than a single model. Monarch combines the global reference field with local crustal information and time-varying corrections to describe the magnetic field where and when operations occur.

Three co-registered magnetic declination surfaces over the Permian Basin labeled IGRF, HDGM, and IFR1, showing progressively finer spatial structure on a shared color scale.
A real SWC-CONUS declination correction time series over 24 hours, with an illustrative survey-time marker.
IFR1 correction at survey time IFR2
Permian Basin example. Magnetic declination across a 30 × 30 km region at 2.50 km MSL, epoch 2026.0. IGRF, HDGM, and IFR1 show progressively finer spatial structure; the time-varying trace is a real SWC-CONUS declination correction for 12 November 2025, with an illustrative survey-time marker.IGRF represents the Low Resolution Geomagnetic Model (LRGM) category used in directional drilling; HDGM is a High Resolution Geomagnetic Model (HRGM); IFR1 uses HDGM with Monarch in-field referencing. The three spatial surfaces share the same color scale. Declination varies by approximately 0.16°, 0.23°, and 1.18° across the region, respectively, with contour intervals of 0.04°, 0.04°, and 0.1°. Data provenance: U.S. Geological Survey (USGS) data contribute throughout these examples; IGRF and HDGM additionally draw on broader international geomagnetic datasets.
1

HDGM

Reference field

A high-resolution global magnetic-field model that provides the reference field for operational magnetic surveying.

Explore HDGM2027
2

IFR1

Local crustal refinement

Regional magnetic information that captures local crustal structure not resolved by the reference field alone.

Explore IFR1
3

IFR2

Time-varying correction

Correction for time-varying changes in the magnetic field, including space-weather effects.

Explore IFR2
Uncertainty + validation Uncertainty estimates and validation against observations show how well the result is known.

Directional drilling

Better magnetic information supports better wellbore positioning.

Magnetic surveying depends on an accurate understanding of the field at the well location and at the time of the survey. Together, HDGM, IFR1, and IFR2 account for the reference field, local crustal effects, and time-varying changes.

Explore directional drilling
Terrain-grounded Permian Basin IFR1 declination correction volume with an illustrative directional wellpath and growing position-uncertainty envelope.
Permian Basin example. IFR1 declination correction through a terrain-grounded model volume, with an illustrative wellpath and growing position-uncertainty envelope. Terrain: satellite-derived elevation data. Regional magnetic data: USGS. Uncertainty envelope is illustrative, not an IFR1 model output. Vertical dimension exaggerated for clarity.

Validation

Validated against observations.

Monarch develops and tests its magnetic-field products against observations, with uncertainty evaluated as part of the modeling process.

Observed and SWC-CONUS-predicted magnetic declination disturbance during a geomagnetic storm, showing close agreement through the day.
SWC-CONUS declination correction, 12 November 2025. Observed and predicted magnetic-field variations at an independent monitoring site. Observed data and SWC-CONUS model inputs: USGS geomagnetic observatories.

Other applications

Beyond directional drilling.

Magnetic navigation

High-resolution magnetic information for navigation and positioning applications.

Geomagnetic observation & monitoring

Measurements, observing systems, and related modeling for characterizing and monitoring Earth's magnetic field.

Explore applications

Contact

Talk with Monarch about your magnetic-field requirements.

Contact us about HDGM2027 licensing, IFR1 coverage for your area of operation, time-varying correction, or another magnetic-field need.

Contact Monarch contact@monarchmag.com
Monarch Magnetics Boulder, Colorado, USA