Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

For mapping and monitoring coral reefs, a bathymetric map is useful as a base map. Different methods have already been developed to map bathymetry using remote sensing. Two main groups can be distinguished. One group is using active remote sensing data; the other is based on passive sensor generated multi-spectral infor- mation. In this article, the focus is on the passive data method. A modified DOP “depth of penetration” mapping method was implemented on a Landsat ETM+ image over Archipélago San Andrés (Colombia). Depth measurements used in the validation of the model were derived from the interpolation of bathymetric maps. The accuracy test revealed that the resulting bathymetric map is useful for coral reef mapping, but care should be taken when using it. Deviations from reality were caused by assumptions inherent to the theory used, data interpolation, satellite im- age characteristics and errors during implementation of the method.

The standardization of geographical names is a search for a suitable official denomination for each geographical feature represented in the maps and charts. Each country strives to conform, according to their own legislation so as to meet the needs of standardization of their geographical names, usually by establishing a Geographical Names Committee. This essay focuses this standardization in Brazil, and the efforts made by the Geographical Names Committee of the National Commission of Cartography (CONCAR) to reduce various issues caused by the lack of standardization.

Over many years, techniques and methods have been developed for the quality evaluation of Digital Terrain Models (DTM). Whereas statistical methods are based on numerical procedures, visual methods depend on the observer’s sensory mecha- nisms, his educational status, his familiarity with DTM, etc., which implies a high degree of subjectivity. Visual methods for DTM analysis may be applied to digital displays and on different computers without resorting to extra data as occurs with statistical methods. Visual methods are classified according to whether the spatial analysis operations are based on a set of data, on multiple data sets, on a statistical spatial analysis or whether they are non-spatial observations. The authors conclude that statistical methods and visual methods are both necessary in this task.

There is a lot of documentation, regulations and standards related to the methodology for geographic information products positional accuracy assessment. Most of them have similar virtues and they suffer the same defects. This paper tries to provide an overview of the most used methodologies for positional accuracy assessment of map- ping products. 

The development of a regional map based on the official geospatial datasets of the National Geography Institutes of Central America and Mexico is an essential ele- ment for the use of people who inhabit the region to aid in their everyday decision making process, both for community and regional scales. This Regional Map of Central America and southern Mexico, integrates elements relating to: political- administrative divisions of the regions —departments, states and provinces— major urban settlements, the roads, water bodies and rivers. The digital map can be used to determine the areas influences and contribute to the prevention and disaster miti- gation to safeguard human lives and natural resources.  Utilizing the participatory mapping approach with support from the Pan Ameri- can Institute of Geography and History (PAIGH) to integrate the geospatial data information between eight countries not only assures the continuity of the project, but also strengthens the relationship between the technical specialists in the region. This type of initiative provides a means to use maps to allow the countries be to able to capture the movements and trends of development of peoples.

The document shows a summary of the existing geodetic infrastructure in 8 coun- tries of Central America and the Caribbean. Through maps and tables it is offered updated concrete figures about the amount and location of the control networks in horizontal, vertical and gravimetric fields. The federal agencies in charge of esta- blishing the national official reference frame explain the technical characteristics of their infrastructure at the time of describing their vision to progress for satisfaction of users like surveyors and high precision cartographers. By analyzing the contents it has been identified a set of similarities and dis- crepancies in the degree of development of the infrastructure among countries. Currently the regional geodetic infrastructure has achieved an impulse enough to satisfy minimal operation requirements. As a coordinated group, the 8 agencies gather a significant set of control marks on the terrain and data bases in constant improvement. From a perspective based in world-wide trends, it can be said that the infrastructure needed for future requirements is compromised due to sympto- matic budget insufficiency, which in cases has driven to stop the progress in verti- cal and gravimetric branches. It is concluded making a recommendation to encourage the specialized training, from where the personnel in the geographic agencies can design custom projects of local extent, able to balance the progress in the three branches of geodetic control.     

This paper has the aim to present the Continual Cartographic Base from Brazil on scale of 1:250.000 – BC250 inside the Permanent Program Updating from IBGE. This program consists in update and maintenance permanent of the whole Brazilian territory, this mean a strategy to subsidize the regions management and also contribute to studies that use environmental politics. These activities of updating require uses of satellite images, like Landsat, CBERS, RapidEye, digital elevation model, information from other institutions and field work. The incorporation of technologies like Geographic Information System and Remote Sensing in the systematic mapping contributed to developing of a base unique and integrated of the whole brazilian territory. The process of construction of BC250 began in 2008, the Brazil was split in parts for cont ract, and finished this mapping process in August of 2012. The first version of this continual vectorial base is available for consulting on the IBGE website <www.ibge.gov.br> since October of 2013 and in the National Infrastructure Spatial Data (INDE) website <www.inde.gov.br> since December of 2013. This cartographic base is the first one to be produced in Brazil with the new standard of  the Geospatial Data Vectorial Structure (EDGV) that contemplate a new structure of storage of geospatial data for integration with data of INDE. 

The visually and hearing impaired users represent a special universe around the world, who need access to information, in this specific case information that is related to environmental problems and their manifestation in various regional pro- cesses such as melting glaciers among others.  The power to represent the spatial relationships between humans and their natu- ral environment is a major challenge with which to achieve the formation of the image mental perception of the average real places and problems. The map helps this as it is an abstraction of what happens in reality in the environmental area, their features and their distributions.  All tactile map product adaptation involves one visual map to provide infor- mation by touch, step that involves a series of steps that are basic recitals to make a tactile mapping, where the end-user features are a major factor importance.  In this process, the evaluation of map products is fundamental because it allows us to check on adaptation achieved its goal of providing information to people who are blind or deaf, if they differ not only textures, shapes, colors between other as- pects also seeks to determine whether the user-understood conceptual part of each of the representations. 

Currently exists several developed and in process of development methods that aim to check the positional accuracy in cartography. The most extended are based in punctual features (NMAS EMAS ASPRS or NSSDA) but exists methods based on lineal elements and even on surface elements. As a result of some recent researches, this article details the most extended methods to check the positional accuracy with lineal elements. It also indicates what would be future investigation guidelines to follow on this matter. For this task, some application cases in several cartographic specialties such as coastal cartography, cadaster, roads or simply the error made by applying various generalization processes to lineal features will be analyzed. With exception of the latter, the other specialties require to get extra data from a more reliable source. Data gathering process is also analyzed because it is the greatest constraint for the application of the aforementioned methods. The advancement of new technologies as well as the geographic databases characteristics, in which usua- lly are stored lineal features, make these methods a way to check the positional accuracy to consider in the future and that will be able to compete whit the already standardized punctual element based methods. 

This contribution describes the cornerstones of the first twenty years of the “Geo- centric Reference System for the Americas” (in Spanish SIRGAS), while it pays tribute to the institutions and personalities that made it possible. In chronological order the story includes: the episodes that led to the establishment of SIRGAS and the context in those days; the establishment of SIRGAS95 as the first continental- wide reference frame compatible with the GPS, and the national densifications implemented by the Latin American countries; the actions aimed at maintaining SIRGAS, including the establishment of SIRGAS2000 and the continuously op- erating SIRGAS network; the efforts to establish a continental-wide vertical ref- erence system compatible with the modern technologies; the building of capacities by the establishment of SIRGAS analysis centres in Latin American institutions; and various activities oriented to contribute to the International As- sociation of Geodesy (IAG) “Global Geodetic Observing System”, the PAIGH “2010-2020 Pan American Agenda”, and the “2013-2015 PAIGH-SIRGAS- CPIDEA-GEOSUR Action Plan to Expedite the Development of Spatial Data Infrastructure of the Americas”.