Techniques for monthly rainfall regionalization in southwestern Colombia.

The knowledge of rainfall regimes is a relevant requirement for many activities such as water resources planning, risk management, agriculture activities management, and other hydrologic applications. The present study has consisted of validating four techniques (one linear, one non-linear, and two hybrids) that allow identifying homogenous regions. We take the monthly rainfall in the Southwestern Colombia (Nariño), an area of 33,268 km2 characterized by complex topography and local factors that can influence the rainfall behavior, to test all techniques. The results showed overall the best performance for the approach related to non-linear principal component analysis and self-organizing map. However, in all mainly prevail two regions: the Andean Region and Pacific Region with a bimodal and unimodal regime, respectively. The bimodal one dominates over the Andes mountains range and the unimodal one the coastal zone. The application of non-linear approaches provided a better understanding of the seasonality of rainfall, and the results may be useful for water resource management.

Comparison of spatial interpolation methods for annual and seasonal rainfall in two hotspots of biodiversity in South America.

The Colombian Biogeographic Choco (CBC) and the La Plata Basin (LPB) are regions with high biodiversity. However, these areas are characterized by scarce climatological information, complex orography, and rain-gauge network unevenly distributed. Interpolated data from the ground station might overcome these aspects. For this reason, is necessary to identify the best technique for the spatial interpolation of rainfall. Hence, the spatial interpolation techniques were applied to annual and seasonal rainfall in the CBC and LPB. Geostatistical results and deterministic approaches were compared by cross-validation. Cokriging with spherical (gaussian) model is the best interpolator in the CBC (LPB), as indicated by the lowest root mean square error (RMSE) and a standardized RMSE close to one. The CBC shows three rainfall cores: the northern, 9,000 mm/year; the central-southern, 10,000 mm/year; and the southern, 7,000 mm/year. The LPB shows a west-east rainfall gradient, with a minimum to the west (450 mm/year) and a maximum in the mid-west (2,000 mm/year). To the north of the LPB, rainfall reaches 1,500 mm/year, while in the south it reaches only 900 mm/year. The results in our study may be useful for scientists and decision-makers for use in environmental and hydrological models for the CBC and the LPB.

Estimation of missing data of monthly rainfall in southwestern Colombia using artificial neural networks.

The success of many projects linked to the management and planning of water resources depends mainly on the quality of the climatic and hydrological data that is provided. Nevertheless, the missing data are frequently found in hydroclimatic variables due to measuring instrument failures, observation recording errors, meteorological extremes, and the challenges associated with accessing measurement areas. Hence, it is necessary to apply an appropriate fill of missing data before any analysis. This paper is intended to present the filling of missing data of monthly rainfall of 45 gauge stations located in southwestern Colombia. The series analyzed covers 34 years of observations between 1983 and 2016, available from the Instituto de Hidrología, Meteorología y Estudios Ambientales (IDEAM). The estimation of missing data was done using Non-linear Principal Component Analysis (NLPCA); a non-linear generalization of the standard Principal Component Analysis Method via an Artificial Neural Networks (ANN) approach. The best result was obtained using a network with a [45-44-45] architecture. The estimated mean squared error in the imputation of missing data was approximately 9.8 mm. month-1, showing that the NLPCA approach constitutes a powerful methodology in the imputation of missing rainfall data. The estimated rainfall dataset helps reduce uncertainty for further studies related to homogeneity analyses, conglomerates, trends, multivariate statistics and meteorological forecasts in regions with information deficits such as southwestern Colombia.

Sistemas de alerta temprana con enfoque participativo: un desafío para la gestión del riesgo en colombia / Early warning systems with a participative approach: a challenge for risk management in colombia

La mayor parte de la población colombiana está en condiciones de riesgo debido a factores hidroclimatológicos, fuertemente influenciados por la variabilidad (VC) y el cambio climático (CC). A esto se suma el aumento de la vulnerabilidad por la inadecuada planificación y ocupación del territorio, propia de países en desarrollo. En este sentido, los sistemas de alerta temprana (SAT) facilitan los procesos de adaptación y mitigación de impactos, por lo que se constituyen en uno de los ejes transversales de la gestión del riesgo. En este trabajo se presenta una reflexión de diversos enfoques y experiencias nacionales e internacionales en SAT. A partir de lo anterior, se identificó que muchos SAT no llegan a ser implementados; y una vez en funcionamiento, existe desequilibrio entre sus componentes. Por otro lado, no se ajustan a las necesidades de los territorios como consecuencia de la escasa participación comunitaria, tanto en la etapa de diseño como en la de operación. Por ello, se considera que para obtener resultados eficaces, que promuevan la construcción de resiliencia, son necesarios SAT con enfoque participativo, que fortalezcan las capacidades de las comunidades para enfrentar las condiciones de riesgo de su entorno.

Most of the Colombian population is facing risks due to hydroclimatological factors, strongly influenced by the climate variability (CV) and climate change (CC). Likewise, vulnerability is continuously increasing because of inadequate land planning and occupation, common in developing countries. Therefore, early warning systems (EWS) facilitate the processes of adaptation and mitigation of impacts, which is why they constitute one of the transverse axes in risk management. This study aimed to review approaches to and field experiences with EWS throughout the world, including Colombia. We identified that many EWS are unimplemented; and once in operation, there exists an imbalance among components. On the other hand, some EWS fail to meet the territory needs as a result of poor community participation, both at design and operation stages. Hence, a participative approach in EWS to tackling risks and building up the capacities of the communities should be promoted for obtaining effective results.

Análisis de aspectos que incrementan el riesgo de inundaciones en Colombia / Analyis of the aaspects which increase the risk of floods in Colombia

Este artículo tiene por objetivo analizar algunos aspectos que potenciaron las inundaciones en Colombia en el periodo 2010/2011. La metodología consistió en la revisión y síntesis de información sobre diferentes enfoques para el manejo de inundaciones, en armonía con la visión ecosistémica y de gestión integral de los recursos hídricos. Los resultados indican que las temporadas de lluvias y el fenómeno La Niña de abril de 2010 a diciembre de 2011 dejaron 5,2 millones de personas afectadas y 683 muertos. Dicho evento es el más crítico en la historia, ya que duplica las pérdidas acumuladas por inundaciones en 30 años. Además de lo anterior, se identifica que el desastre se debió a una suma de factores, entre los que destacan: cambios en la cobertura vegetal; las deficiencias en la gestión del suelo y los recursos hídricos; las debilidades en el diseño y gestión de infraestructura, en los patrones de crecimiento demográfico; los problemas institucionales en la prevención y atención de emergencias; la falta de transparencia y la corrupción; una legislación que carece de metodologías para aplicación, de recursos fiscales y de mecanismos para el seguimiento y medición resultados; entre otros. Una de las conclusiones es la necesidad de incluir nuevos conocimientos del clima en la gestión del riesgo y la planificación pero, sobre todo, es recomendable abordar el manejo de las inundaciones con un enfoque diferente, migrando hacia procesos integrales y con mayor capacidad de adaptación de la sociedad colombiana en los próximos años, mediante una gestión del riesgo de inundación más eficiente, acorde a conceptos modernos y en armonía con los procesos de desarrollo sostenible.

The main objective of this article is to analyze some aspects that fostered floods in Colombia in the period 2010/2011. The methodology followed was a review and synthesis of information on different approaches to flood management, in harmony with the ecosystemic vision and integrated management of water resources. The results indicate that the rainy season and La Niña phenomenon from April 2010 to December 2011 left 5,2 million people affected and 683 people dead. This has been the most critical event in history, because it doubled the accumulated losses from flooding in 30 years. Besides the above, it has been identified that the disaster was due to a combination of factors, among which are: changes in vegetation cover, deficiencies in the management of land and water resources, the weaknesses in the design and management of infrastructure, the population growth patterns, the institutional problems in the prevention and emergency care, lack of transparency and corruption, legislation that lacks enforcement methodologies, fiscal resources and mechanisms for monitoring and measuring the results, among others. One conclusion is the need to include new knowledge on climate, risk management and planning, but above all, it is recommended to address the management of floods with a different approach, migrating to more comprehensive processes and with a higer adaptation capacity from the Colombian society in the coming years through a more efficient flood risk management, in accordance with the modern concepts and in harmony with sustainable development processes.

Adaptación a la variabilidad y el cambio climático: intersecciones con la gestión del riesgo / Adatation to varriability and climate change: intersections with risk managemenet

Dado el aumento en la frecuencia de eventos hidro meteorológicos extremos, asociados a la variabilidad climática y/o cambio climático, y la mayor vulnerabilidad de las sociedades humanas frente a estas amenazas, se presenta un mayor interés en la reducción de gases de efecto invernadero por parte de la comunidad científica, este artículo resalta la importancia de la adaptación para la reducción del riesgo de desastre asociado al tiempo, el clima y sus intersecciones con la gestión del riesgo. Se concluye, que la adaptación y la gestión del riesgo, deben integrase con una visión holística para reducir la vulnerabilidad de la sociedad, además de articularse con iniciativas de mitigación para reducir las causas que generan el cambio climático, reduciendo el riesgo existente y evitando la construcción social de nuevos factores de riesgo.

Given the increase in the frequency of extreme hydro-meteorological events associated with climate variability and/or climate change, and to the increased vulnerability of human societies before those hazards, a higher interest in reducing greenhouse gases by the scientific community appears. This article highlights the importance of adaptation for disaster risk reduction associated with the weather, the climate and their intersections with risk management. It is concluded that adaptation and risk management should be integrated with a comprehensive view to reduce society's vulnerability and gets articulated with mitigation initiatives to reduce the causes that generate climate change, thus reducing the existent risk and avoiding the social construction of new risk factors.

Interdisciplinariedad: desafío para la educación superior y la investigación / Intrdisciplinariity: a challenge for higher education and research

En los últimos años, los problemas globales han aumentado en complejidad y conectividad, especialmente los ambientales (crisis del agua, cambio climático, demanda de energía, crecimiento poblacional, etc.), lo que obliga a enfocarlos como complejos, inseparables y retroalimentados. La sectorización del pensamiento, trabajo e indicadores de rendimiento (enfocados generalmente a indicadores económicos), son obstáculos para alcanzar metas más integrales, intensificándose el trabajo fraccionado, la especialización, el enfoque sectorial y el individualismo sobre el enfoque sistémico. A partir de lo anterior, surge la necesidad de implementar una visión holística, integral e interdisciplinaria para resolver los problemas actuales, que sólo se logra con el trabajo en equipo. En este artículo, se describen los diferentes conceptos de abordaje del conocimiento y se plantea la necesidad de hacer cambios en la educación superior y la investigación, para abordar estos problemas cada vez más complejos. Se concluye que el desarrollo humano sostenible puede abordarse desde diferentes disciplinas, pero ninguna por sí sola podrá responder a sus principales problemas, siendo muy poco lo que aportan los equipos multidisciplinarios si los expertos de cada disciplina ofrecen sólo una visión técnica de su especialidad, sin articular el conocimiento con las demás.

In recent years, global problems have increased in complexity and connectivity, especially those environmental (water crisis, climate change, energy demand, population growth, etc.) which forces to focus them as complex, inseparable, and feed backed. Thought sectioning and work and performance indicators (generally focused on economical indicators) are obstacles for the achievement of more comprehensive goals, intensifying in divided work, specialization, sectional focus and individualism over the systemic approach. From this premise it appears the need to implement a holistic, comprehensive, and interdisciplinary vision in order to solve current problems which can only be achieved through team work. In this article the different concepts to deal with knowledge are described and the need to make some changes in higher education and research processes to face these everyday more complex problems is considered. It is concluded that sustainable human development can be dealt with from different disciplines, but none by itself will answer its main problems being not much what interdisciplinary teams contribute if the experts in each discipline offer only a technical vision of their specialty without articulating knowledge with the others.