Analysis of interdecadal Variability of Temperature Extreme Events in Argentina applying EVT

La frecuencia de ocurrencia de los eventos extremos de temperatura ha sufrido variaciones a lo largo del último siglo: se han observado tendencias positivas significativas en las noches cálidas y tendencias negativas en las noches frías en todo el mundo. En Argentina, la probabilidad de ocurrencia de extremos cálidos anuales de la temperatura máxima disminuyó en las últimas décadas, mientras que hubo un incremento en la probabilidad de ocurrencia de extremos cálidos anuales de la temperatura mínima. El objetivo principal de este trabajo es evaluar la variabilidad interdecadal observada en la distribución de los eventos de temperatura que superan un determinado umbral en cinco estaciones meteorológicas de Argentina durante el periodo 1941-2000, mediante la aplicación de la teoría de valores extremos. La disponibilidad de datos diarios permite el ajuste de la distribución generalizada de Pareto (DGP) a las anomalías diarias de temperatura que exceden el percentil 90 o que no alcanzan el percentil 10 con el propósito de estimar los valores de retorno de los eventos extremos. Las series de anomalías diarias de temperatura se dividen en tres subperiodos consecutivos sin superposición de 20 años cada uno. La DGP se ajusta en cada uno de los tres subperiodos en forma independiente y se comparan los valores de retorno estimados en cada subperiodo. Los resultados muestran que hay una disminución en la intensidad de eventos extremos cálidos durante todo el periodo de estudio, junto con un incremento en su frecuencia de ocurrencia durante los últimos 20 años del siglo XX. Los extremos fríos también muestran una disminución en intensidad. Sin embargo, los cambios en su frecuencia de ocurrencia no son tan consistentes entre las diferentes estaciones estudiadas.The frequency of occurrence of temperature extreme events has changed throughout the last century: significant positive trends in warm nights and negative trends in cold nights have been observed all over the world. In Argentina, the probability of occurrence of warm annual extremes of maximum temperature has decreased in the last decades, while there has been an increase in warm annual extremes of minimum temperature. The main objective of this paper is to evaluate observed interdecadal changes in the distribution of temperature events that exceed a fixed threshold in five meteorological stations from Argentina over the period 1941-2000, by applying the extreme value theory (EVT). The availability of daily data allows fitting a generalized Pareto distribution (GPD) to daily temperature anomalies over the 90th or below the 10th percentile, in order to estimate return values of extreme events. Daily temperature anomalies are divided into three consecutive and non-overlapping subperiods of 20 years. GPD is fitted to each subperiod independently and a comparison is made between return values estimated in each subperiod. Results show that there is a decrease in the intensity of warm extreme events during the whole period, together with an increase in its frequency of occurrence during the last 20 years of the twentieth century. Cold extremes also show a decrease in their intensity. However, changes in their frequency of occurrence are not so consistent between the different stations analyzed.Fil: Tencer, Barbara. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria; ArgentinaFil: Rusticucci, Matilde Monica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria; Argentin

Climate and Health in Buenos Aires: A Review on Climate Impact on Human Health Studies Between 1995 and 2015

In this review, seven pieces of research on climate variability and its impact on human health in Buenos Aires City between 1995 and 2015 were evaluated. The review highlighted continuities and ruptures in the methodology, variables, and statistics data of the research, considering their similarities and differences in the period of study and the methodology applied. Contributions, pending issues, and public policies on climate change challenges in the city aimed at improving living conditions were considered. Six studies contributed evidence on the relationship between climate and health and its impacts on the population; two studies suggested the development of early warning systems and one study is a preliminary approach.Fil: Fontan, Silvia Graciela. Universidad Nacional de La Matanza; ArgentinaFil: Rusticucci, Matilde Monica. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Summer seasonal predictability of warm days in Argentina: statistical model approach

Predicting extreme temperature events can be very useful for different sectorsthat are strongly affected by their variability. The goal of this study is toanalyze the influence of the main atmospheric, oceanic, and soil moistureforcing on the occurrence of summer warm days and to predict extremetemperatures in Argentina northern of 40°S by fitting a statistical model. In apreliminary analysis, we studied trends and periodicities. Significant positivetrends, fundamentally in western Argentina, and two main periodicities ofsummer warm days were detected: 2?4 years and approximately 8 years.Lagged correlations allowed us to identify the key predictors: ElNiño-Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), andStandardized Precipitation Indices (SPI). We also noticed that the frequency ofwarm days in spring acts as a good predictor of summer warm days. Due to thecollinearity among many predictors, principal component regression was usedto simulate summer warm days. We obtained negative biases (i.e., the modeltends to underestimate the frequency of summer warm days), but the observedand simulated values of summer warm days were significantly correlated,except in northwest Argentina. Finally, we analyzed the predictability of thesummer warm days under ENSO neutral conditions, and we found newpredictors: the geopotential height gradient in 850 hPa (between the AtlanticAnticyclone and the Chaco Low) and the Atlantic Multidecadal Oscillation(AMO), while the PDO and SPI lost some relevance.Fil: Collazo, Soledad Maribel. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria; ArgentinaFil: Barrucand, Mariana Graciela. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria; ArgentinaFil: Rusticucci, Matilde Monica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria; Argentin

Atmospheric circulation influence on temperature and precipitation individual and compound daily extreme events: Spatial variability and trends over southern South America

Southern South America (SSA) is an extended region where temperature and precipitation daily extreme events have several impacts on the different socio-economic activities. In this work, their individual and compound occurrence over SSA and their association with atmospheric circulation were studied during 1979–2015, using meteorological stations and the CPC gridded dataset. Results were generally in good agreement between both datasets. The occurrence of a warm night (minimum temperature exceeding the 90th percentile) or a cold day (maximum temperature below the 10th percentile) significantly increases the probability of heavy precipitation (daily precipitation exceeding the 75th percentile) in southern Chile and southeastern South America. These compound events were regionally conditioned by specific circulation types. In addition, both individual and compound extremes showed trends in the different sub-regions. On one hand, heavy precipitation exhibited a significant increase over central-eastern Argentina and Uruguay, northeastern Argentina and southern Brazil during the warm season, and a significant decrease in central and southern Chile during the cold season. On the other hand, warm (cold) extremes generally presented significant upward (downward) trends. Compound events showed significant positive trends for selected regions, in some cases coincident with trends in individual extremes. Changes in the frequency of circulation patterns were found to partly influence some of these trends, like the increases in heavy precipitation and warm extremes during the warm season.Fil: Olmo, Matías Ezequiel. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Instituto Franco-Argentino sobre Estudios del Clima y sus Impactos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bettolli, Maria Laura. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Franco-Argentino sobre Estudios del Clima y sus Impactos; ArgentinaFil: Rusticucci, Matilde Monica. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Franco-Argentino sobre Estudios del Clima y sus Impactos; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentin

Association between El Niño and extreme temperatures in southern South America in CMIP5 models. Part 1: model evaluation in the present climate

Climate variability might temporarily improve or mitigate the effects of increasingglobal warming. Understanding and estimating internal variability is just as important as understandingthe role of anthropogenic forcing, as the combination of both drives climate events in thereal world. The objective of this work is to analyze the relationship between the SST of the equatorialPacific and 4 extreme temperature indices in southern South America considering griddedobservational data (HadEX3), reanalyses (ERA-Interim, NCEP1, NCEP2), and global climatemodels participating in the Coupled Model Intercomparison Project Phase 5 (CMIP5) in the historicalperiod 1979−2005. For this, correlations and quantile regression for the 90th percentilewere estimated between the variables. Moreover, to assess the performance of the reanalysis andCMIP5 models, multiple metrics were calculated. The observations showed that warm conditionsin the equatorial Pacific are mainly associated with a higher occurrence of warm nights in thenorth and center of Argentina and Chile in winter and spring. However, the different reanalysesconsidered in this study showed discrepancies in representing these relationships. Several CMIP5models were generally able to simulate correlation patterns for the warm extremes of the minimumand maximum temperature in comparison to HadEX3. These types of studies are critical tounderstanding whether climate models simulate temperature extremes in association with physicalprocesses, providing greater confidence in their future projections.Fil: Collazo, Soledad Maribel. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Barrucand, Mariana Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; ArgentinaFil: Rusticucci, Matilde Monica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Variability and predictability of winter cold nights in Argentina

Extreme cold events can cause crop damage as well as an increase in energy demand and even in the mortality rate. Identifying the atmospheric processes associated with the occurrence of these extremes would allow decision-makers to implement preventive and mitigation actions. The goal of this study is to identify predictors of cold extremes of minimum temperature during winter in Argentina (north of 40 °S), and their modulation by the different El Ni~no-Southern Oscillation (ENSO) phases for the period 1970?2015. Lagged correlation analysis between winter cold nights and several global and regional climate indices identified ENSO, subtropical jet intensity, position and intensity of the South Pacific Anticyclone (SPA), and a blocking index as the dominating forcings. The El Niño phase is associated with a decrease in the occurrence of cold extremes. In addition, an increase in the number of blocking events together with a weaker subtropical jet and, a less intense and northward shift of the SPA also inhibit the occurrence of cold extremes of the minimum temperature. Our results indicate persistence in the winter cold nights series compared with the previous season in eastern Argentina. Twowinters with opposite extreme conditions (high and low frequency of cold nights) were selected as case studies. Since both cases occurred under ENSO neutral conditions, we also searched for cold nights predictors consideringonly neutral years. We detected the presence of an equivalent barotropic structure located in southeastern Pacific in both events, which confirmed the importance of the SPA intensity and blocking events as predictors in absenceof an active El Niño.Fil: Collazo, Soledad Maribel. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Barrucand, Mariana Graciela. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rusticucci, Matilde Monica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Relationship between mortality and extreme temperatures in Buenos Aires and Rosario

En este trabajo se examinan las relaciones entre las temperaturas extremas y la mortalidad en verano en las ciudades de Buenos Aires y Rosario para el establecimiento de un alerta de olas de calor con aplicación a la salud. Se encuentra que en ambas ciudades existe una relación tipo U entre la mortalidad y las temperaturas máximas, mínimas y aparentes diarias entre los años 2001/2012. De esta manera se muestra que la población porteña y rosarina es susceptible a la ocurrencia de periodos de altas temperaturas. Mediante el análisis de las olas de calor con afectación en la mortalidad vemos que los hombres y mujeres son afectados por exceso de calor en igual proporción relativa a su población parcial y los adultos mayores a 65 años acaparan entre el 70-80 % de los fallecidos. Para ayudar desde la meteorología a la salud, se desarrollaron Sistemas de Alerta de Olas de Calor y Salud en ambas ciudades, y operados por el Servicio Meteorológico Nacional. Los mismos tienen el objetivo de anticipar a la población situaciones meteorológicas extremas y sus posibles efectos en salud, para que la misma aumente los recaudos frente a las olas de calor.In this paper the associations between summer heat waves and mortality in Buenos Aires and Rosario is studied. Both cities have an ‘U’ relationship between daily mortality and maximum, minimum and apparent temperatures over the 2001-2012 period. The population over both cities is susceptible to extreme high temperatures. Men and women are equally affected, but people over 65 represent 70-80% by analyzing heat waves. Alert systems were implemented in both cities trough the National Weather Service with the aim of anticipate extreme meteorological situations to the population.Fil: Almeira, Gustavo. Ministerio del Interior, Obras Públicas y Vivienda. Secretaría de Obras Públicas. Subsecretaría de Recursos Hídricos. Instituto Nacional del Agua y del Ambiente (Ezeiza); Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; ArgentinaFil: Rusticucci, Matilde Monica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Suaya, Martina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Ministerio de Defensa. Secretaria de Planeamiento. Servicio Meteorológico Nacional; Argentin

Towards a Latin American Health & Climate Observatory: Seminary on Instrumentation and Methodologies

El estudio de la relaci n entre clima y salud requiere la articulaci n de diversos actores y disciplinas. En este art culo se presenta la experiencia del Seminario Latinoamericano Instrumentos y Metodolog as para un observatorio de clima y salud, realizado en Buenos Aires en 2019, apoyado por el Centro Latinoamericano de Formaci n Interdisciplinaria (CELFI), como un espacio de vinculaci n, capacitaci n y referencia a experiencias que se vienen desarrollando en este campo en Am rica Latina. En este trabajo se presenta el dise o del seminario, su contenido, did ctica y desarrollo, as  como los resultados en cuanto a participaci n, productos y evaluaci n. Asimismo, durante el proceso se reflexiona en torno a las metodolog as que permitan articular diferentes disciplinas en un proceso de construcci n de conocimiento sobre la relaci n clima-salud. Finalmente, se explicitan los principales lineamientos del observatorio, surgidos de una instancia de intercambio con actores clave. El desarrollo del seminario, los proyectos presentados como producto, las discusiones surgidas durante el intercambio y la continuidad de trabajo en los meses posteriores permiten dar cuenta de la importancia y necesidad de construir interdisciplinariamente este observatorio para Am rica Latina y el Caribe.O estudo da relação entre o clima e a saúde requere a articulação de diversos atores e disciplinas. Neste artigo, apresenta-se a experiência do Seminário Latino-americano Instrumentos e Metodologias para um observatório de clima e saúde, realizado em Buenos Aires em 2019. Foi apoiado pelo Centro Latino-americano de Formação Interdisciplinar (CELFI), como espaço de vinculação, capacitação e referência das experiências que se estão a desenvolver neste campo na América Latina. Neste trabalho, apresentase a conceção do seminário, o seu conteúdo, dinâmica e desenvolvimento, bem como, os resultados em termos de participação, produtos e avaliação. Da mesma forma, durante o processo, é feita uma reflexão sobre as metodologias que permitem a articulação de diferentes disciplinas, num processo de construção do conhecimento sobre a relação clima-saúde. Por fim, explicitam-se as principais diretrizes do observatório, decorrentes de uma plataforma de intercâmbio dos atores chave. O desenvolvimento do seminário, os projetos apresentados como produto, as discussões ocorridas durante o intercâmbio e a continuidade de trabalho nos meses seguintes, permitem perceber a importância e a necessidade de construir este observatório interdisciplinar, para a América Latina e Caribe.The study of the relationship between health and climate requires articulating various actors and disciplines. This paper presents the experience of the Latin American Seminar on Instruments and Methodologies for a climate and health observatory— held in Buenos Aires in 2019 and supported by the Latin American Center for Interdisciplinary Training (CELFI)—as a linking and training facility referencing the projects that are being carried out in this field throughout Latin American. This paper presents the design, contents, didactic approach and execution of the seminar, as well as its results regarding participation, products and evaluation. Likewise, the methodologies that could allow articulating different disciplines in a process of gainingknowledge about the climate-health relationship are reflected throughout this process. Finally, the main guidelines for this observatory, arising from an exchange with key actors, are set forth herein. The execution of the seminar, the projects presented as the products thereof, the discussions that arose during the exchange, and the need to continue with this work over the following months point out to the importance and necessity of building this observatory for Latin America and the Caribbean in an interdisciplinary way.Fil: Rusticucci, Matilde Monica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fontan, Silvia Graciela. Universidad Nacional de la Matanza. Departamento de Cs. de la Salud; ArgentinaFil: Abrutzki, Rosana. Universidad de Buenos Aires. Facultad de Ciencias Sociales. Instituto de Investigaciones "Gino Germani"; ArgentinaFil: Bartolomeu, María Lucía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Chesini, Francisco. Ministerio de Salud de la Nación; ArgentinaFil: Mantilla, Gilma. Pontificia Universidad Javeriana; Colombi

Central and South America

The chapter is divided into two main sections. The first section follows an integrative approach in which hazards, exposure, vulnerability, impacts and risks are discussed following the eight climatically homogeneous sub-regions described in WGI AR6 (Figure 12.1). The second section assesses the implemented and proposed adaptation practices by sector; in doing so, it connects to the WGII AR6 crosschapter themes. The storyline is then a description of the hazards, exposure, vulnerability and impacts providing as much detail as is available in the literature at the sub-regional level, followed by the identification of risks as a result of the interaction of those aspects. This integrated sub-regional approach ensures a balance in the text, particularly for countries that are usually underrepresented in the literature but that show a high level of vulnerability and impacts, such as those observed in CA. The sectoral assessment of adaptation that follows is useful for policymakers and implementers, usually focused and organised by sectors, government ministries or secretaries that can easily locate the relevant adaptation information for their particular sector. To ensure coherence in the chapter, a summary of the assessed adaptation options by key risks is presented, followed by a feasibility assessment for some relevant adaptation options. The chapter closes with case studies and a discussion of the knowledge gaps evidenced in the process of the assessment.EEA Santa CruzFil: Castellanos, Edwin J. Universidad del Valle de Guatemala; Guatemala.Fil: Lemos, Maria Fernanda. Pontifical Catholic University of Rio de Janeiro; Brasil.Fil: Astigarraga, Laura. Universidad de la República; Uruguay.Fil: Chacón, Noemí. Instituto Venezolano de Investigaciones Científicas; Venezuela.Fil: Cuvi, Nicolás. Facultad Latinoamericana de Ciencias Sociales (FLACSO); Ecuador.Fil: Huggel, Christian. University of Zurich; Switzerland.Fil: Miranda Sara, Liliana Raquel. Foro Ciudades para la Vida; Peru.Fil: Moncassim Vale, Mariana. Federal University of Rio de Janeiro; Brasil.Fil: Ometto, Jean Pierre. National Institute for Space Research; Brasil.Fil: Peri, Pablo Luis. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; Argentina.Fil: Peri, Pablo Luis. Universidad Nacional de la Patagonia Austral; Argentina.Fil: Peri, Pablo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Postigo, Julio C. Indiana University; Estados Unidos.Fil: Ramajo Gallardo, Laura. Adolfo Ibanez University; Chile.Fil: Roco, Lisandro. Catholic University of The North; Chile.Fil: Rusticucci, Matilde Monica. Universidad de Buenos Aires; Argentina

Observed and simulated variability of extreme temperature events over South America

This invited review paper tends to summarise the results based on the variability of occurrence of temperature extremes in South America. The first thing to note is that there is a geographical imbalance with respect to the number of published studies on temperature extremes. Most of the results come from the southern part of South America, east of the Andes, and a few from the northern part of the continent and for the Altiplano. The workshop organised by the ETCCDMI in Brazil was the first time to have the opportunity to collect information in a regional way and present trends in extreme daily temperatures. A better geographical picture enhanced with more data show significant geographical trends in warm (positive) and cold (negative) nights over Southern South America and over the northern South America coast. All other studies based on smaller regions also agree in finding the most significant trends in the evolution of the minimum temperature, with positive trends in almost all studies on the occurrence of warm nights (or hot extremes of minimum temperature) and negative trend in the cold extremes of the minimum. On the other hand, there is little agreement on the variability of maximum temperature. Generally the maximum temperature in southern South America has decreased, in opposition to the case of northern South America where it has increased. Strong decadal and interannual variability have been found in the occurrence of cold extremes. Reanalysis and climate models underestimate the intensity of extremes, mainly near the Andes. The studies trying to understand the dynamics of the circulation that leads to the occurrence of these extremes are analysed from its occurrence in almost all scales from the synoptic, intraseasonal, seasonal, annual, and multi-year linear trend with different methodologies, also, indentifying the local and remote forcing. A gap was found in studies that relate some specific local forcing (like changes in land use) and compare it with the remote ones. Different aspects of the occurrence of the temperature extremes are still missing in some regions of the continent.Fil: Rusticucci, Matilde Monica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ciencias de la Atmósfera y los Océanos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria; Argentin