Martinez J. A. auteur aut IRD Junquas Clémentine auteur aut IRD Bozkurt D. auteur aut IRD Viale M. auteur aut IRD Fita L. auteur aut IRD Trachte K. auteur aut IRD Campozano L. auteur aut IRD Arias P. A. auteur aut IRD Boisier J. P. auteur aut IRD Condom Thomas auteur aut IRD Goubanova K. auteur aut IRD Pabón-Caicedo J. D. auteur aut IRD Poveda G. auteur aut IRD Solman S. A. auteur aut IRD Sörensson A. A. auteur aut IRD Espinoza Jhan-Carlo auteur aut IRD text journalArticle eng text/pdf reformatted digital access The Andes is the longest mountain range in the world, stretching from tropical South America to austral Patagonia (12 degrees N-55 degrees S). Along with the climate differences associated with latitude, the Andean region also features contrasting slopes and elevations, reaching altitudes of more than 4,000 m. a.s.l., in a relatively narrow crosswise section, and hosts diverse ecosystems and human settlements. This complex landscape poses a great challenge to weather and climate simulations. The interaction of the topography with the large-scale atmospheric motions controls meteorological phenomena at scales of a few kilometers, often inadequately represented in global (grid spacing similar to 200-50 km) and regional (similar to 50-25 km) climate simulations previously studied for the Andes. These simulations typically exhibit large biases in precipitation, wind and near-surface temperature over the Andes, and they are not suited to represent strong gradients associated with the regional processes. In recent years (similar to 2010-2024), a number of modeling studies, including convection permitting simulations, have contributed to our understanding of the characteristics and distribution of a variety of systems and processes along the Andes, including orographic precipitation, precipitation hotspots, mountain circulations, gravity waves, among others. This is Part I of a two-part review about atmospheric modeling over the Andes. In Part I we review the current strengths and limitations of numerical modeling in simulating key atmospheric-orographic processes for the weather and climate of the Andean region, including low-level jets, downslope winds, gravity waves, and orographic precipitation, among others. In Part II, we review how climate models simulate surface-atmosphere interactions and hydroclimate processes in the Andes Cordillera to offer information on projections for land-cover/land-use change or climate change. With a focus on the hydroclimate, we also address some of the main challenges in numerical modeling for the region. specialized atmospheric modeling Andes complex terrain mountain hydroclimate mesoscale meteorology AMERIQUE DU SUD ANDES 021 020 12 1427783 [23 ] 2024 https://www.documentation.ird.fr/hor/fdi:010092141 10.3389/feart.2024.1427783 [F B010092141] https://www.documentation.ird.fr/hor/fdi:010092141 https://horizon.documentation.ird.fr/exl-doc/pleins_textes/2025-01/010092141.pdf IRD - Base Horizon / Pleins textes 2025-01-22 2025-11-06 fdi:010092141 fre