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GPS velocities across the northeast trending Eastern Cordillera of Colombia show oblique convergence at 8.8 ± 1.7 mm/yr, consisting of 8.0 ± 1.7 mm/yr of right‐lateral strike‐slip shear along the mountain range and 3.7 ± 0.3 mm/yr of northwest southeast shortening. Faster convergence occurs only at the northeast end of the Cordillera, where its eastern edge trends northwest and the highest mountains lie. The strike‐slip shear corroborates geologic work suggesting such movement southwest and northeast of the range. Given the ~200 km width of the Eastern Cordillera, the ~100–150 km of crustal shortening inferred from balanced cross sections and implied by recent estimates of crustal thickness would require ~25–40 Myr of shortening at ~4 mm/yr. The present‐day GPS measurements, therefore, are inconsistent with the inference, based on paleobotanical observations that the entire Eastern Cordillera rose 1500–2500 m since 3–6 Ma and called for a different interpretation of those data.

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In this work an attempt to identify the role of the interplanetary magnetic field (IMF) in the response of the ionosphere to different solar phenomena is presented. For this purpose, the day‐to‐day variability of the equatorial ionospheric anomaly (EIA) and the main ionospheric disturbances are analyzed during one coronal mass ejection (CME) and two high‐speed solar wind streams (HSSWSs). The EIA parameters considered are the zonal electric field and both the strength and position of its northern crest. The disturbances being the prompt penetration of magnetospheric electric field (PPMEF) and disturbance dynamo electric field (DDEF) are studied using the magnetic response of their equivalent current systems. In accordance, ground‐based Global Navigation Satellite Systems receivers and magnetometers at geomagnetic low latitudes in the American sector are used. During both phenomena, patterns of PPMEF related to fluctuations of the IMF are observed. Diurnal and semidiurnal magnetic oscillations are found to be likely related to DDEF. Comparisons among the EIA parameters and the DDEF magnetic response exhibit poor relation during the CME in contrast to good relation during the HSSWSs. It is concluded that the response of the low‐latitude ionosphere to solar phenomena is largely determined through the oscillation frequency of the IMF Bz by affecting the generation of the PPMEF and DDEF differently. This is seen as an effect of how the energy from the solar wind is transferred into the magnetosphere‐ionosphere system.

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Cartagena is subsiding at a higher rate compared to that of global climate-driven sea level rise. We investigate the relative sea level rise (RSLR) and the influence of vertical land movements in Cartagena through the integration of different datasets, including tide gauge records, GPS geodetic subsidence data, and Interferometric Synthetic Aperture Radar (InSAR) observations of vertical motions. Results reveal a long-term rate (> 60 years) of RSLR of 5.98 ± 0.01 mm/yr. The last two decades exhibited an even greater rate of RSLR of 7.02 ± 0.06 mm/yr. GPS subsidence rates range between − 5.71 ± 2.18 and − 2.85 ± 0.84 mm/yr. InSAR data for the 2014–2020 period show cumulative subsidence rates of up to 72.3 mm. We find that geologically induced vertical motions represent 41% of the observed changes in RSLR and that subsidence poses a major threat to Cartagena’s preservation. The geodetic subsidence rates found would imply a further additional RSLR of 83 mm by 2050 and 225 mm by 2100. The Colombian government should plan for the future and serve as an example to similar cities across the Caribbean.

Se analizó la tendencia del ascenso del nivel del mar en Cartagena con respecto a otros puertos en el mar Caribe en el contexto de los cambios que se aprecian en la  línea de costa en la región. La comparación entre mapas del sur de la Bahía de Cartagena elaborados en 1735 y 2011 evidenció la desaparición de islas y zonas de manglar en una amplia zona del área suroeste. La pérdida de zona costera en la Bahía se refleja en una mayor tasa de ascenso del nivel del mar en Cartagena debido a la subsidencia local, lo cual requiere de acciones inmediatas de prevención. Los datos geodésicos de la estación GPS instalada sobre el techo de la edificación del Centro de Investigaciones Oceanográficas e Hidrográficas, CIOH, revelaron una posible subsidencia en la región de la Isla de Manzanillo, la cual podrá contrastarse con los datos que puedan obtenerse de una estación empotrada sobre la superficie terrestre. © 2017. Acad. Colomb. Cienc. Ex. Fis. Nat.