Adaptation strategies to climate change in the Tropics: analysis of two multifactorial systems (high-altitude Andean ecosystems and Plasmodium falciparum malaria infections)

In this dissertation I focus my analyses of adaptation strategies to climate change on two areas of primary concern: (i) high-altitude ecosystems of the Tropical Andes, with particular interest in the so-called páramo ecosystems; and (ii) mosquito-borne diseases, focusing on Plasmodium falciparum malaria infections. My research on páramo ecosystems follows a six-tiered approach to understand the linkages between the ongoing changes in climatic conditions and the disruptions affecting the integrity of high-altitude environments. Activities conducted herein include the analyses of changes in atmospheric stability and lifting condensation levels; the diagnosis of changes in hydrological regimes; the assessment of the extent of life zones; the analyses of increases in the occurrence and rapid spread of high-altitude fires; the assessment of the integrity of páramo ecosystems; and the analyses of increases in climatic stress. Activities are conducted for three key, strategic, protected high-altitude Andean environments of the Tropical Andes and for the full length of the Andes Cordillera. My research findings provide elements for an improved understanding of the potential responses of Andean ecosystems to the large-scale rapidly changing climate and to a strongly-influential natural interannual variability. My research on P. falciparum malaria focuses on the analysis of the complexity behind the transmission dynamics of this multi-factorial disease. A deep understanding of such a complexity is possible through a holistic examination of the climatic, biological, socioeconomic, and demographic key-factors that are driving the fluctuations, changes and trends in malaria incidence. I propose a multi-model ensemble of malaria process-based models to offer useful information that could effectively guide decision-makers in risk assessment, malaria control investments and choice of interventions. I work on the integration of short-, medium- and long-term climate predictions into simulations of future changing scenarios, while helping to set up environment-informed systems at municipal level. My research thus provides a framework to: (a) compare the simulation outputs of several malaria process-based models with actual malaria morbidity profiles observed in several endemic- and epidemic-prone pilot sites in Colombia and Kenya; (b) explore the role that both climatic and non-climatic factors play in fluctuations and trends in malaria incidence, and analyze key confounders; (c) assess changing climate and future scenarios, and estimate the timing and possible magnitude of unexpected malaria outbreaks; (d) investigate current decision making processes, simulate the impact of indoor residual spraying campaigns, and provide quantitative goals for effective interventions; (e) conduct stability analysis; (f) pose and answer "what if" questions; and (g) stimulate an interactive learning environment to help decision makers learn

The history and creation of the Agenda 2030: Designing the sustainable development goals.

This article analyzes and studies the history and background of the Sustainable Development Goals (SDGs). Firstly, a historical journey has been made to understand the evolution and development of education up to the arrival of the 2030 Agenda for Sustainable Development action plan. In this way, a timeline was presented that reflects the path taken by the United Nations and the international community to arrive at To reach this new international framework. In this line, the post-2015 agenda, conferences, summits and international decades have been examined, as they were decisive events for the adoption of the SDGs. A official UN documents and programmes were analysed, demonstrating the enormous volume of documentation that has been published on the subject. There is no better way to understand the international interest generated by the proposed topic than to read the "Preamble1" of Resolution A/RES/70/1, 25September 2015, Transforming our world: the United Nations 2030 Agenda for Sustainable Development. In this document you can find the new proposal for a better and higher quality future for all people on the planet.pre-print281 K

Two-tiered reconstruction of Late Pleistocene to Holocene changes in the freezing level height in the largest glacierized areas of the Colombian Andes

One way of deducing vertical shifts in the altitudinal distribution of Colombian high-altitude páramo environments is by inferring fluctuations in the height of the local freezing level. In our research, we are implementing two complementary approaches to reconstruct Late Pleistocene to Holocene changes in the freezing level height (FLH) in two of the most extensively glacier-covered areas of the northern Andes. We combined remote sensing and field-based geomorphological mapping with time-series reconstruction of changes in the altitude of the 0°C isotherm. Changes in the FLH were based on already-published ∼30 kyr paleo-reconstructions of sea surface temperatures (SSTs) of the eastern tropical Pacific and the western tropical Atlantic, as well as on reconstructed long-term sea level changes and empirical orthogonal functions of present-day (historical) Indo-Pacific and tropical Atlantic SST anomalies. We also analyzed the probability distribution of air-sea temperature differences and the spatial distribution of grid points with SSTs above the minimum threshold necessary to initiate deep convection. We considered available historical near-surface and free air temperature data of ERA-Interim reanalysis products, General Circulation Model (GCM) simulations, weather stations, and (deployed by our group) digital sensors, to assess the normal Environmental Lapse Rates (ELRs) at the regional to local scale. The combined maps of glacial landforms and our reconstructed FLHs provided us with a well-founded inference of potential past glacier advances, narrowing down the coarse resolution of ice margins suggested by previous research efforts. The extent of the areas with temperatures below the freezing point suggested here for the summits of our main study site exceeds in magnitude the corresponding glacier icecaps and front advances proposed by previous studies. Conversely, our average lowest altitudes of the FLH for our comparative site are consistently above the main glacier-front advances previously suggested. Our results indicate that, compared to the maximum upward changes that likely took place over the past ca. observed (present-day) upward shifts of the FLH have occurred at a rate that significantly surpasses our inferred rates. Our study helps fill the gaps in understanding past climatic changes and present trends in the region of interest and provides some insights into analyzing the signals of natural and anthropogenic climate change

An integrated simulation and optimization model of sheep farms as a tool to explore technical and environmental objectives

Peer ReviewedPublishe

Proteómica redox diferencial: identificación de proteínas oxidadas reversiblemente en respuesta a hipoxia

Comunicaciones a congreso

Climate and environmental monitoring for decision making

As human populations grow, so do the resource demands imposed on ecosystems and the impacts of our global footprint. Natural resources are not invulnerable, nor infinitely available. The environmental impacts of anthropogenic actions are becoming more apparent – air and water quality are increasingly compromised, pests and diseases are extending beyond their historical boundaries, and deforestation is exacerbating flooding downstream and loss of biodiversity. Society is increasingly becoming aware that ecosystem services are not only limited, but also that they are threatened by human activities. The need to better consider long-term ecosystem health and its role in enabling human habitation and economic activity is urgent. In this context IRI conducts research to understand the impact of climate and environmental changes on different sectors including agriculture, water management, human health, and natural disasters. Through exhaustive, rigorous evaluation, analysis and interpretation of remotely-sensed products and in-situ measurements, IRI ensures its partners have access to the most reliable and relevant information about the climate and environment in a format that best informs their decision making and planning. We focus on monitoring satellite-derived and in-situ estimates of precipitation, temperature, vegetation, water bodies, evapotranspiration, and land cover. Ultimately, the new products developed at IRI in partnership with other institutions at national (e.g. NOAA, NASA, USGS) and international (e.g. National Meteorology Agencies, UN FAO) levels are integrated into operational early-warning systems for health, natural disasters, agriculture, and food security. The new products which monitor in almost real-time climate and environmental conditions are made available through two online data bases at IRI called IRI Data Library and Map Room. In this paper we present the products developed at IRI and how they are integrated into Early Warning Systems (EWS). We also discuss IRI’s experience in linking EWS into decisions and policies using the fire early warning system as a concrete example

Testing a multi-malaria-model ensemble against 30 years of data in the Kenyan highlands

Background: Multi-model ensembles could overcome challenges resulting from uncertainties in models’ initial conditions, parameterization and structural imperfections. They could also quantify in a probabilistic way uncertainties in future climatic conditions and their impacts. Methods: A four-malaria-model ensemble was implemented to assess the impact of long-term changes in climatic conditions on Plasmodium falciparum malaria morbidity observed in Kericho, in the highlands of Western Kenya, over the period 1979–2009. Input data included quality controlled temperature and rainfall records gathered at a nearby weather station over the historical periods 1979–2009 and 1980–2009, respectively. Simulations included models’ sensitivities to changes in sets of parameters and analysis of non-linear changes in the mean duration of host’s infectivity to vectors due to increased resistance to anti-malarial drugs. Results: The ensemble explained from 32 to 38% of the variance of the observed P. falciparum malaria incidence. Obtained R2-values were above the results achieved with individual model simulation outputs. Up to 18.6% of the variance of malaria incidence could be attributed to the +0.19 to +0.25°C per decade significant long-term linear trend in near-surface air temperatures. On top of this 18.6%, at least 6% of the variance of malaria incidence could be related to the increased resistance to anti-malarial drugs. Ensemble simulations also suggest that climatic conditions have likely been less favourable to malaria transmission in Kericho in recent years. Conclusions: Long-term changes in climatic conditions and non-linear changes in the mean duration of host’s infectivity are synergistically driving the increasing incidence of P. falciparum malaria in the Kenyan highlands. User-friendly, online-downloadable, open source mathematical tools, such as the one presented here, could improve decision-making processes of local and regional health authorities

Matching Dendrochronological Dates with the Southern Hemisphere ¹⁴C Bomb Curve to Confirm Annual Tree Rings in Pseudolmedia rigida from Bolivia

This study used high-precision radiocarbon bomb-pulse dating of selected wood rings to provide an independent validation of the tree growth periodicity of Pseudolmedia rigida (Klotzsch & H. Karst.) Cuatrec. from the Moraceae family, collected in the Madidi National Park in Bolivia. ¹⁴C content was measured by accelerator mass spectrometry (AMS) in 10 samples from a single tree covering over 70 yr from 1939 to 2011. These preliminary calendar dates were determined by dendrochronological techniques and were also used to select the samples for ¹⁴C AMS. In order to validate these preliminary dates using the established Southern Hemisphere (SH) ¹⁴C atmospheric concentration data set, the targeted rings were selected to be formed during periods before and after the ¹⁴C bomb spike nuclear tests (i.e. 1950s–1960s). The excellent agreement of the dendrochronological dates and the ¹⁴C signatures in tree rings associated with the same dates provided by the bombpulse ¹⁴C atmospheric values for the SH (SHCal zone 1–2) confirms the annual periodicity of the observed growth layers, and thus the high potential of this species for tree-ring analysis. The lack of discrepancies between both data sets also suggests that there are no significant latitudinal differences between the ¹⁴C SHCal zone 1–2 curve and the ¹⁴C values obtained from the selected tree rings at this geographic location (14°33′S, 68°49′W) in South America. The annual resolution of P. rigida tree rings opens the possibility of broader applications of dendrochronological analysis for ecological and paleoclimatic studies in the Bolivian tropics, as well as the possibility of using wood samples from some tree species from this region to improve the quality of the bomb-pulse ¹⁴C SHCal curve at this latitude

Laboratory estimation of the effects of increasing temperatures on the duration of gonotrophic cycle of Anopheles albimanus (Diptera: Culicidae)

The increase of malaria transmission in the Pacific Coast of Colombia during the occurrence of El Niño warm event has been found not to be linked to increases in the density of the vector Anopheles albimanus, but to other temperature-sensitive variables such as longevity, duration of the gonotrophic cycle or the sporogonic period of Plasmodium. The present study estimated the effects of temperature on duration of the gonotrophic cycle and on maturation of the ovaries of An. albimanus. Blood fed adult mosquitoes were exposed to temperatures of 24, 27, and 30 degrees C, held individually in oviposition cages and assessed at 12 h intervals. At 24, 27, and 30 degrees C the mean development time of the oocytes was 91.2 h (95% C.I.: 86.5-96), 66.2 h (61.5-70.8), and 73.1 h (64-82.3), respectively. The mean duration of the gonotrophic cycle for these three temperatures was 88.4 h (81.88-94.9), 75 h (71.4-78.7), and 69.1 h (64.6-73.6) respectively. These findings indicate that both parameters in An. albimanus are reduced when temperatures rose from 24 to 30 degrees C, in a nonlinear manner. According to these results the increase in malaria transmission during El Niño in Colombia could be associated with a shortening of the gonotrophic cycle in malaria vectors, which could enhance the frequency of man-vector contact, affecting the incidence of the disease