Scientists have created a new model to understand the Earth’s inner workings, with a focus on the Arctic region. They used data from deep inside the Earth to explain how heat and movement in the mantle (the layer beneath the crust) affect the surface, including plate tectonics and the formation of ocean ridges.
In the Arctic, they found a warmer section of the mantle that is contributing to the splitting of the Earth’s surface under the ocean.
This warmer area is also causing more methane to be released as permafrost melts, which is worsening climate change. The study also explains why parts of Greenland are melting faster due to heat coming from deep inside the Earth.
This research helps scientists better understand the natural forces shaping the Arctic and its impact on climate.
The new geodynamic model of the modern Earth, with a particular focus on the Arctic region, has been constructed based on the SMEAN 2 global seismic tomography model. Researchers utilized the CitcomS code, applying seismic tomography data to develop a spherical Earth model.
This enabled the solution of the Stokes equation for a viscous fluid, allowing scientists to examine temperature anomalies and mantle flow velocity fields that explain key features of the Arctic’s geodynamics.
The study reveals that global convection cells have developed in the Earth’s mantle, which are fundamental to the planet’s geodynamics.
These cells drive mantle flows, influencing plate tectonics, mid-ocean ridges, and subduction and collision zones. Furthermore, smaller upper mantle convective cells are shown to create regional structures that manifest on the Earth’s surface.
The region of Iceland and the eastern part of Greenland, under the influence of mantle upwelling, is characterized by a hot subcrustal mantle and increased heat flow at the surface, causing instability and melting of the Greenland ice sheet from below.
In the Arctic, the research highlights the presence of a moderately warm region in the upper mantle beneath the Arctic Ocean and the shelf of northeast Asia. Subhorizontal mantle flows in this region are facilitating passive rifting, contributing to the Arctic’s geological development.
The study also identifies a significant temperature difference between the subcrustal mantle under the western Arctic shelf (including the Barents and Kara seas) and the eastern Arctic shelf (from the Laptev Sea to the Bering Strait), with the latter being up to 100 degrees warmer.
This temperature disparity is linked to increased methane emissions from the shallow shelf of the Eastern Arctic, where permafrost degradation and the breakdown of gas hydrates are taking place amid elevated environmental temperatures. Methane, a potent greenhouse gas, is known to intensify the warming of the Arctic, further impacting the region’s climate.
The model also highlights notable geodynamic activity in areas like Iceland and Greenland. Mantle upwelling in these regions is contributing to a hot subcrustal mantle and increased heat flow at the surface, which is causing instability in the Greenland ice sheet, accelerating its melting from below.
The findings provide critical insights into the geodynamic processes shaping the Arctic and could enhance our understanding of climate impacts in this sensitive region.