The present work has as objective the elaboration of a new gridded data base to 16 km, for the analysis of the changes of the future climate on Peru, mainly in the variables of precipitation, maximum and minimum temperature. The methodology used is the dynamic regionalization technique, using the regional climate model Weather Research and Forecasting (WRF), using the initial conditions of the HadGEM2-ES global model, for the period of 1981-2065, with the RCP 8.5 emission scenario. The analysis of the results for the observed period indicates a better representation of the precipitation in the central and southern part of the Peruvian Andes and overestimation mainly in the summer period (December, January and February). With regard to temperatures, there is a better representation of the minimum temperature compared to the maximum. While the results of the changes to 2030 indicate non-un...

Due to its complex topography, the Lake Titicaca region, located in the southern tropical Andes, presents great challenges for atmospheric modeling. This study aims to improve the representation of precipitation and air surface temperature using the Weather Research and Forecasting (WRF) model at high spatial resolution (2 km), during the austral summer of 2020. We conducted 11 experiments with different configurations of topography, land use, physical parameterizations, and lake surface temperature (LST). Each experiment was evaluated considering in-situ data from the Peruvian-Bolivian region and gridded precipitation products. For precipitation, the best configuration, with an average bias close to zero mm, includes using the GMTED2010 topography (not smoothed) and the land use data of Eva et al. (2004), along with the Purdue Lin microphysics and the Grell 3D cumulus scheme. For air te...

La presente tesis presenta una descripción de la reducción de escala dinámica, para la generación de información proyectada hacia el 2050 sobre el territorio del Perú para el análisis de posibles cambios en la precipitación para el periodo comprendido entre los años 2036-2065 respecto al periodo de referencia 1981-2005 en base a las condiciones iniciales y de contorno del modelo global HadGEM2-ES en el escenario de emisiones RCP 8.5. Se ha realizado en el presente trabajo énfasis en la metodología utilizada; la reducción de escala dinámica mediante el modelo meteorológico “Weather Research and Forecasting” (WRF).

WCRP VAMOS/CORDEX LACII - Workshop

El SENAMHI viene desarrollando exitosas campañas de sensibilización para que las personas estén mejor preparadas frente a los efectos dañinos de la radiación ultravioleta (RUV), en particular informando sobre el índice ultravioleta (UVI por sus siglas en inglés) que es un valor numérico que expresa en forma sencilla el peligro a exponerse a quemadura solar por la irradiancia solar en el rango ultravioleta. El pronóstico de este índice es una de las actividades operativas que se realiza a nivel mundial por casi todos los servicios meteorológicos del mundo y el SENAMHI lo viene realizando desde hace varios años aunque en forma limitada y restringida a 10 ciudades del país. Desde nuestro punto de vista, esta limitación se debe a dos razones: la primera es que se vincula el pronóstico estrictamente a los puntos de observación en superficie y la segunda porque no se utilizan h...

“El SENAMHI viene desarrollando exitosas campañas de sensibilización para que las personas estén mejor preparadas frente a los efectos dañinos de la radiación ultravioleta (RUV), en particular informando sobre el índice ultravioleta (UVI por sus siglas en inglés) que es un valor numérico que expresa en forma sencilla el peligro a exponerse a quemadura solar por la irradiancia solar en el rango ultravioleta. El pronóstico de este índice es una de las actividades operativas que se realiza a nivel mundial por casi todos los servicios meteorológicos del mundo y el SENAMHI lo viene realizando desde hace varios años aunque en forma limitada y restringida a 10 ciudades del país. Desde nuestro punto de vista, esta limitación se debe a dos razones: la primera es que se vincula el pronóstico estrictamente a los puntos de observación en superficie y la segunda porque no se utiliza...

Los posibles cambios en el comportamiento de la temperatura y precipitación para 2016-2045, relativos al período 1971-2000, en las localidades de Urubamba y granja Kcayra, ubicadas en Cusco, Andes centrales de Sudamérica, se han estimado mediante la técnica multivariada de Componentes Principales y sus Funciones Ortogonales Empíricas asociadas. Los datos corresponden a los medidos desde instrumental convencional de precipitación, temperatura máxima y mínima en el período 1965-2012. Los datos de vientos y temperatura en altura pertenecen al reanálisis ERA40 (1971-2000), la precipitación regional a CMAP (1979-2000). Asimismo, los datos numéricos de temperatura en altura y precipitación son provenientes de los modelos climáticos globales CCSM4, HadGEM2-ES, MPI-ESM-LR del Proyecto de Intercomparación de Modelos Acoplados (CMIP5), en sus periodo histórico 1971-2000 y futuro 20...

Los posibles cambios en el comportamiento de la temperatura y precipitación para 2016-2045, relativos al período 1971-2000, en las localidades de Urubamba y granja Kcayra, ubicadas en Cusco, Andes centrales de Sudamérica, se han estimado mediante la técnica multivariada de Componentes Principales y sus Funciones Ortogonales Empíricas asociadas. Los datos corresponden a los medidos desde instrumental convencional de precipitación, temperatura máxima y mínima en el período 1965-2012. Los datos de vientos y temperatura en altura pertenecen al reanálisis ERA40 (1971-2000), la precipitación regional a CMAP (1979-2000). Asimismo, los datos numéricos de temperatura en altura y precipitación son provenientes de los modelos climáticos globales CCSM4, HadGEM2-ES, MPI-ESM-LR del Proyecto de Intercomparación de Modelos Acoplados (CMIP5), en sus periodo histórico 1971-2000 y futuro 20...

Automobile emissions in urban cities, such as Peru, are significant; however, there are no published studies of the effects of these emissions on PM2.5 (fine particulate matter) formation. This study aims to analyze the contributions of vehicle aerosol emissions to the surface mass concentration of PM2.5 in the Metropolitan Area of Lima and Callao (MALC), one of the most polluted cities in Latin America and the Caribbean (LAC) known to have high concentrations of PM2.5. In February 2018, we performed two numerical simulations (control and sensitivity) using the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem). We considered both trace gasses and aerosol emissions from on-road traffic for the baseline simulation (hereinafter referred to as “control”); gasses without particulate emissions from vehicles were considered for the sensitivity simulation (hereinafter ...

Fourteenth meeting of the Research Dialogue, Venue of Centro Mundial de Conferencias de Bonn

This study investigates the spatial and temporal characteristics of cold surges that propagates northward along the eastern flank of the Andes from subtropical to tropical South America analysing wintertime in situ daily minimum temperature observations from Argentina, Bolivia and Peru and ERA-40 reanalysis over the 1975–2001 period. Cold surges usually last 2 or 3 days but are generally less persistent in the southern La Plata basin compared to tropical regions. On average, three to four cold surges are reported each year. Our analysis reveals that 52 % of cold episodes registered in the south of La Plata basin propagate northward to the northern Peruvian Amazon at a speed of around 20 m s−1. In comparison to cold surges that do not reach the tropical region, we demonstrate that these cold surges are characterized, before they reach the tropical region, by a higher occurrence of a s...

The Weather Research and Forecasting-Chemistry (WRFChem) model was used to develop an operational air quality forecast system for the Metropolitan Area of Lima-Callao (MALC), Peru, that is affected by high particulate matter concentrations episodes. In this work, we describe the implementation of an operational air quality-forecasting platform to be used in the elaboration of public policies by decision makers, and as a research tool to evaluate the formation and transport of air pollutants in the MALC. To examine the skills of this new system, an air pollution event in April 2016 exhibiting unusually elevated PM2.5 concentrations was simulated and compared against in situ air quality measurements. In addition, a Model Output Statistic (MOS) algorithm has been developed to improve outputs of inhalable particulate matter (PM10) and fine particulate matter (PM2.5) from the WRF-Chem model. ...

Hydrological hazards related to flash floods (FF) in Peru have caused many economic and human life losses in recent years. In this context, developing complete early warning systems against FF is necessary to cope impacts. For this purpose, hydrological and hydraulic models coupled to numerical weather models (NWM) that provide forecasts are generally used. In this sense, the National Meteorological and Hydrological Service of Peru (SENAMHI) has launched the ANDES initiative (Operational Forecasting System for Flash Floods of SENAMHI in English) to support FF events.

We evaluate the benefits of the use of a regional coupled model over its stand-alone atmospheric component when forced by reanalysis data in the simulation of the South American climate. We find that the coupling allows for a better simulation of important features of the atmospheric circulation and surface temperature. The simulated 2 meters air temperature is improved over most of the continent, the sea level pressure over the South Pacific Anticyclone area is better represented in the coupled simulation and the location of the ITCZ is improved during the austral winter. The precipitation, especially over the Andes, benefits less from the coupling, although a more realistic humidity transport leads to a reduction of the precipitation biases over extensive regions. The austral summer precipitation bias is reduced in areas such as eastern Colombia, northern Bolivia, eastern Brazil and ce...

Runoff from glacierised Andean river basins is essential for sustaining the livelihoods of millions of people. By running a highresolution climate model over the two most glacierised regions of Peru we unravel past climatic trends in precipitation and temperature. Future changes are determined from an ensemble of statistically downscaled global climate models. Projections under the high emissions scenario suggest substantial increases in temperature of 3.6 °C and 4.1 °C in the two regions, accompanied by a 12% precipitation increase by the late 21st century. Crucially, significant increases in precipitation extremes (around 75% for total precipitation on very wet days) occur together with an intensification of meteorological droughts caused by increased evapotranspiration. Despite higher precipitation, glacier mass losses are enhanced under both the highest emission and stabilization e...

Esta investigación se realizó en el marco de los proyectos Perú GROWS y PEGASUS

Se estima que para el año 2080 la temperatura en la región amazónica aumentará en 4°C, lo que tendrá implicancias directas en el equilibrio de sus ecosistemas. Teniendo en cuenta que el 50 por ciento de las precipitaciones en la Amazonía son producidas por convección, es decir, son provocadas por las transferencias de aire caliente y frío en la región, siendo en gran medida efecto de la autorregulación de una región dominada por extensas zonas de bosque húmedo, el problema del cambio climático, unido a los procesos progresivos de deforestación, se convierte en uno de los problemas más preocupantes para la región y el mundo. Sin duda alguna, esta capacidad de autorregulación ya se está viendo afectada. Hay que tener en cuenta que un 40 o 45 por ciento de deforestación en la Amazonía provocaría un desastre irreparable de implicancias mundiales. La presente publicació...

Peruvian glaciers are important contributors to dry season runoff for agriculture and hydropower, but they are at risk of disappearing due to climate warming. Their energy balance and ablation characteristics have previously been studied only for individual glaciers, with no comparisons between regions. We applied the physically-based, energy balance melt component of the model Tethys-Chloris at five on-glacier meteorological stations: three in the Cordillera Blanca near Huaraz (with glaciers above ~4300 m a.s.l.), and two in the Cordillera Vilcanota east of Cusco (with glaciers above ~ 4800 m). The climate of these regions is strongly seasonal, with an austral summer wet season and winter dry season. Our results revealed that at most sites the energy available for melt is greatest in the wet season. This is a consequence of the dry season energy losses from the latent heat flux and net ...