Horizons in Earth Science Research. Volume 20 first provides an overview of geodesy throughout the past six decades, providing a short glimpse of emerging technology that is expected to enable rapid advances in many branches of science in the decades to come. Next, the performance of two wavelength dispersive X-ray fluorescence spectrometers possessing rhodium anode have been compared to assess their usefulness in limnological studies, using bottom sediments from Araxà , Minas Gerais, Brazil. The authors reviews the applications of infrared absorption spectroscopy in the fields of condensed matter physics and earth sciences. Infrared absorption spectroscopy is mainly associated with interactions between atoms and vibrational phonons of materials. Additionally, a comparative study held at different drainage systems in Araxà , Minas Gerais, Brazil is presented with the aim of evaluating the performance of The Constant Flux: Constant Sedimentation and Constant Rate of Supply models. Following this, monazite and rutile geochronology and Zr-in-rutile thermometry are used to understand the thrust age and thermochronology of the Araçuaí/Ribeira Orogenic System-São Francisco Craton transition in southeastern Brazil. Recent work on neurotoxin-producing microalgae (dinoflagellates) is presented wherein effects from space weather may display the hormetic dose-response, either through geomagnetic activity or solar X-ray flux. Lastly, the authors provide a soft-computing approach to forecast 30-year-ahead annual rainfall in Tehran, Iran. A time-series of yearly data covering more than one century was used for the design of ensemble projections to understand and quantify the uncertainty associated with intradecadal-to-interdecadal predictability.