The rocky surface of the Earth is continuously attacked by the agents of weathering and erosion — water, ice, wind, temperature change, and chemical reactions — that break down solid rock into smaller fragments, dissolve minerals, and transport material from highlands to lowlands and ultimately to the ocean. These processes operate on timescales from seconds (a rockfall triggered by freeze-thaw action) to millions of years (the slow chemical weathering of granite), and together they determine the shape of landscapes, the composition of soils, and the chemical composition of rivers and oceans. The science of geomorphology — the study of landforms and the processes that create them — sits at the interface of geology, hydrology, ecology, and climate science.
tonnes of soil eroded globally per year
of soil takes 200-1000 years to form
of land severely degraded globally
people affected by land degradation
Physical (mechanical) weathering breaks rock into smaller fragments without changing its chemical composition. Freeze-thaw weathering — the most effective physical weathering process in cold climates — occurs when water enters cracks in rock, freezes, and expands by approximately 9% in volume, exerting pressures of up to 2,000 atmospheres that widen the crack with each cycle. In warm, arid climates, thermal expansion and contraction as rock heats during the day and cools at night generates sufficient stress to cause surface spalling. Pressure release (exfoliation) occurs when deeply buried rock is exposed by erosion of overlying material — the confining pressure is released and the rock expands, forming curved fractures parallel to the surface that cause large sheets of rock to peel away, as spectacularly seen in Yosemite's granite domes.
Research into this field has expanded significantly over the past decade, with studies conducted across six continents revealing both shared patterns and important regional variations. Long-term ecological monitoring programmes — some spanning more than 50 years — have been particularly valuable in distinguishing cyclical variation from directional trends, and in identifying the ecological thresholds beyond which ecosystems shift to alternative states that may be difficult or impossible to reverse.
The application of remote sensing technologies — satellite imagery, LiDAR, acoustic monitoring, and environmental DNA — has transformed the scale and resolution at which ecological patterns can be detected and analysed. Where field surveys once required years of intensive effort to characterise a single site, modern sensor networks and automated analysis pipelines can monitor hundreds of sites simultaneously, providing datasets of unprecedented spatial and temporal coverage.
Geology rarely makes headlines until a volcano erupts or the ground starts shaking. But the processes described here operate continuously beneath our feet — shaping the landscapes we live in, determining where mineral resources are found, and setting the stage for natural disasters that can reshape human history in a matter of hours. Dr. Vasquez has spent years in the field measuring these processes directly: core-sampling sediments off the coast of Iceland, instrumenting active fault zones in southern Italy, and mapping lava flows in Hawaii. What emerges from this work is a picture of a planet that is far more dynamic — and far more consequential in its behaviour — than most people appreciate.
The past decade has seen remarkable advances in geological monitoring — dense seismometer networks, satellite InSAR that detects millimetres of ground deformation from orbit, continuous GPS arrays that track the slow creep of tectonic plates. These tools are changing what is possible in terms of early warning and hazard assessment. But translation from scientific understanding to public safety remains incomplete in many parts of the world, particularly in developing countries where the population exposed to geological hazards is largest and scientific infrastructure thinnest. Bridging that gap is one of the defining challenges of applied Earth science in the coming decades.
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