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This article presents the characteristics of the small islands of Tidore and Hiri, which are vulnerable to the dangers of volcanic eruptions in Indonesia. The physical condition of the area is very important for carrying out a sustainable disaster risk reduction analysis; therefore, climate and topographic data are important to know. The limited availability of data in the study area causes climate data to be obtained from NASA’s Earth Science Data Systems (ESDS) and regional topographical presentation of Indonesia’s national DEM data. The results show that in the period 2004 to 2014, the temperature in the study area ranged from 292 K to 309 K. The islands of Tidore and Hiri have monthly precipitation between 50 mm to 500 mm.

With growing concerns regarding future impacts of sea-level in major coastal cities, the most accurate information is required regarding local sea-level changes with respect to the coast. Besides global and regional sea-level changes, local coastal vertical ground motions can substantially contribute to local changes in sea-level. In some cases, such ground motions can also limit the usefulness of tide-gauge records, which are a unique source of information to evaluate global sea-level changes before the altimetry era. Using satellite synthetic aperture radar interferometry, this study aims at characterizing vertical coastal ground motion in Dakar (Senegal), where a unique century-long record in Africa has been rediscovered. Given the limited number of available images, we use a stacking procedure to compute ground motion velocities in the line of sight over 1992–2010. Despite a complex geology and a rapid population growth and development, we show that the city as a whole is unaffected by differential ground motions larger than 1 mm year −1. Only the northern part of the harbor displays subsidence patterns after 2000, probably as a consequence of land reclamation works. However, these ground motions do not affect the historical tide gauge. Our results highlight the value of the historical sea-level records of Dakar, which cover a 100 year time-span in a tropical oceanic region of Africa, where little data are available for past sea-level reconstructions.