The use of numerical weather prediction (NWP) model to dynamically downscale coarse climate reanalysis data allows for the capture of processes that are influenced by land cover and topographic features. Climate reanalysis downscaling is useful for hydrology modeling, where catchment processes happen on a spatial scale that is not represented in reanalysis models. Selecting proper parameterization in the NWP for downscaling is crucial to downscale the climate variables of interest. In this work, we are interested in identifying at least one combination of physics in the Weather Research Forecast (WRF) model that performs well in our area of study that covers the Baker River Basin and the Northern Patagonian Icecap (NPI) in the south of Chile. We used ERA-Interim reanalysis data to run WRF in twenty-four different combinations of physics for three years in a nested domain of 22.5 and 4.5 km with 34 vertical levels. From more to less confident, we found that, for the planetary boundary layer (PBL), the best option is to use YSU; for the land surface model (LSM), the best option is the five-Layer Thermal, RRTM for longwave, Dudhia for short wave radiation, and Thompson for the microphysics. In general, the model did well for temperature (average, minimum, maximum) for most of the observation points and configurations. Precipitation was good, but just a few configurations stood out (i.e., conf-9 and conf-10). Surface pressure and Relative Humidity results were not good or bad, and it depends on the statistics with which we evaluate the time series (i.e., KGE or NSE). The results for wind speed were inferior; there was a warm bias in all of the stations. Once we identify the best configuration in our experiment, we run WRF for one year using ERA5 and FNL0832 climate reanalysis. Our results indicate that Era-interim provided better results for precipitation. In the case of temperature, FNL0832 gave better results; however, all of the models’ performances were good. Therefore, working with ERA-Interim seems the best option in this region with the physics selected. We did not experiment with changes in resolution, which may have improved results with ERA5 that has a better spatial and temporal resolution.

Solar Radiation Management (SRM) is a climate intervention strategy aimed at mitigating global warming by reducing incoming solar radiation. We investigate the potential influence of SRM on Andean glacier-wide surface mass balance, as glaciers are crucial for downstream ecological functions along the west coast of South America. We numerically simulate the surface mass balance response of thousands of glaciers to SRM and other climate change scenarios throughout the 21^st century. Results indicate Pan-Andean negative mass balance, irrespective of the scenario or glacier-climate regimes. However, SRM tends to modify interannual variability and temperature sensitivity in several regions. Our findings also suggest that if SRM had been implemented in the late 1980’s, it would have been effective in avoiding the negative trajectory seen today. The Andes feature nearly all mountain hydroclimatic regimes, representing a globally relevant example of SRM impacts. These findings emphasize the urgency of drastic emissions reduction.

Es fundamental conocer la avifauna de una región, ya sea a escalas amplias o locales debido a que en base a estos datos se pueden generar distintas acciones con propósitos variados, que van desde su simple conocimiento hasta su eventual manejo. Para brindar evidencia científica robusta que permita contribuir al conocimiento y conservación de aves se investigó el efecto de la estacionalidad sobre la riqueza y abundancia de especies de aves dentro del Parque Ecológico y Cultural Rucamanque, Sitio Prioritario para la Conservación de la Biodiversidad de la Región de la Araucanía. Desde octubre de 2018 a septiembre de 2019 mediante la realización de 12 campañas de muestreo se evaluaron la riqueza y abundancia para la avifauna tanto diurna como nocturna en 41 puntos de recuento distribuidos dentro del Parque. Se observó un total de 3130 aves pertenecientes a 49 especies, de las cuales 32 se identificaron como residentes permanentes, seis residentes de verano, dos residentes de invierno y 9 esporádicas. De las 49 especies registradas, 9 no fueron reportadas en estudios realizados con anterioridad. En términos de composición, se observaron diferencias tanto en su riqueza como en su abundancia, las cuales variaron según la estacionalidad. Los resultados valorizan al Parque como un Sitio Prioritario para la Conservación de la Biodiversidad al albergar una rica comunidad de aves y confirman la necesidad de monitorear el estado de las poblaciones, ya que se encuentran en un escenario bajo constantes presiones antropogénicas.

Over land, the freezing level height (FLH) is a critical free-atmosphere parameter that controls ice and snow extents and shapes mountain hydroclimates, including streamflow and surface albedo. We assess future FLH trajectories under two Solar Radiation Modification (SRM) scenarios from the Geoengineering Model Intercomparison Project, phase 6 (GeoMIP6’s G6solar and G6sulfur) and two greenhouse gas emission pathways (SSP2-4.5, SSP5-8.5) to evaluate potential hydroclimatic impacts. We use output fields from models CNRM-ESM2-1 and IPSL-CM6A-LR. To improve accuracy in FLH projections, we applied a Quantile Delta Mapping (QDM) technique to mitigate inherent biases in climate simulations, using ERA5 reanalysis data as a reference. Results thus far show higher FLH values in tropical regions and lower values near the poles. However, the FLH meridional gradient is stronger in the southern hemisphere than in the northern hemisphere for the historical simulations—consistent with ERA5. Globally, the annual maximum FLH increases ~6 m/year for the GeoMIP6 and SSP2-4.5 scenarios between 2020 and 2100, whereas SSP5-8.5 nearly doubles this rate. For most of the world, this increase is strongly correlated with near-surface air temperature rise, suggesting a strong coupling between surface warming and free-atmosphere conditions along high-elevation regions in the future, irrespective of the climate scenario. Although annual and maximum FLHs show linear relationships with near-surface air temperature, the regression slope of the former is, on average, about 100 m/°C smaller than the latter, suggesting a stronger change during the melt season and hence a possible large impact on the high mountain cryosphere. In this presentation, we will showcase these findings together with ongoing analyses using other SRM simulations, and discuss their potential implications for mountain hydroclimates worldwide.

Our study assesses the differences in intensity and frequency of Atmospheric Rivers (ARs) between Solar Radiation Modification (SRM) scenarios and greenhouse gas emission pathways. ARs are among the most important freshwater sources in the midlatitudes. This tropical humidity, transported horizontally to extratropical regions as plumes of water vapor, is associated with extreme precipitation at landfall, which usually triggers natural hazards, such as landslides and floods, especially in arid, semi-arid, and Mediterranean regions. While Earth System Models project more intense AR events and poleward displacement of landfall locations as warming deepens during the 21st century, driven by changes of atmospheric dynamics such as the position of the descending branch of the Hadley Cell, little is known about how SRM’s global warming mitigation goals may alter atmospheric circulation patterns and hence AR characteristics, especially in the Southern Hemisphere. We compare two SRM scenarios, G6Solar (reduction of the solar constant) and G6Sulfur (Stratospheric Aerosol Injection), and two CMIP6 model outputs under greenhouse gas emission pathways SSP2-4.5 and SSP5-8.5. Results reveal an overall decrease in AR frequency in extratropical regions by the end of the century. Conversely, the mid-latitudes experience increases in AR frequency. Under G6solar, frequency change is of similar magnitude as for the SSP2-4.5 scenario, whereas the G6sulfur scenario matches SSP5-8.5’s closest. Regarding ARs’ intensity, we detect worldwide increases in transported moisture content, irrespective of scenarios, with a small decrease near the west coast of South America. The role of SRM on projected changes in the dynamics and thermodynamics of the processes is discussed. These results signal that the Southern Hemisphere’s atmospheric dynamics are not neutral to the SRM technique, as they may deliver a significantly different AR scenario by the end of the century, even if the intended global cooling goals are met.