1,721,078 research outputs found
Tropical cyclone effects on Arctic Sea ice variability
No full textIn recent years increasing interest has been put on the role that intense Tropical Cyclones can play in the climate system. The following study is aimed at highlighting the effects of strong Tropical Cyclones over the Tropical Atlantic on the mean climate. Their composite effect on the surface winds is made apparent by a wide cyclonic perturbation that affects a large portion of the Atlantic tropical Ocean. Teleconnection patterns, which are visible in the Sea Level Pressure anomalies associated with this Tropical Composite Cyclone, appear to link the activity of the hurricanes to the Arctic Ocean. A significant negative correlation between the energy dissipated by hurricanes in the Tropical atmosphere and the sea ice cover along the Transpolar Drift Stream path, has also been found. Citation: Scoccimarro, E., S. Gualdi, and A. Navarra (2012), Tropical cyclone effects on Arctic Sea ice variability, Geophys. Res. Lett., 39, L17704, doi:10.1029/2012GL052987
Changes in Tropical Cyclone Activity due to Global Warming: Results from a High-Resolution Coupled General Circulation Model
No full textcharacteristics of tropical cyclones (TCs). The analysis has been performed using scenario climate simulations carried out with a fully coupled high-resolution global general circulation model. The capability of the model to reproduce a reasonably realistic TC climatology has been assessed by comparing the model results from a simulation of the twentieth century with observations. The model appears to be able to simulate tropical cyclone-like vortices with many features similar to the observed TCs. The simulated TC activity exhibits realistic geographical distribution, seasonal modulation, and interannual variability, suggesting that the model is able to reproduce the major basic mechanisms that link TC occurrence with large-scale circulation. The results from the climate scenarios reveal a substantial general reduction of TC frequency when the atmospheric CO2 concentration is doubled and quadrupled. The reduction appears particularly evident for the tropical western North Pacific (WNP) and North Atlantic (ATL). In the NWP the weaker TC activity seems to be associated with reduced convective instabilities. In the ATL region the weaker TC activity seems to be due to both the increased stability of the atmosphere and a stronger vertical wind shear. Despite the generally reduced TC activity, there is evidence of increased rainfall associated with the simulated cyclones. Finally, the action of the TCs remains well confined to the tropical region and the peak of TC number remains equatorward of 20 degrees latitude in both hemispheres, notwithstanding the overall warming of the tropical upper ocean and the expansion poleward of warm SSTs
Análisis de los escenarios climáticos presentes y futuros. In “Informe de valoración de los impactos de actividades antrópicas y del cambio climático”. Producto C – Doc. 25051-REL-T010.0. World Bank Tender: Adaptation to Climate Change Impacts on the Coastal Wetlands in the Gulf of Mexico (PR. P100438).
No full textGracias al nuevo conjunto de simulaciones climáticas para el siglo XXI, realizadas con los modelos de circulación global (GCM) que fueron producidos para el Proyecto de Intercomparación de Modelos Acoplados, fase cinco (CMIP5, Meehl y Bony, 2012) se da la posibilidad de investigar los cambios futuros en el clima promedio en el Sureste de México. El presente análisis toma en cuenta dos posibles trayectorias, RCP8.5 y RCP4.5, de las llamadas trayectorias representativas de concentración de gases de efecto invernadero (RCP) consideradas como escenarios potenciales e ilustrativos del futuro hasta llegar al 2100, en el CMIP5.
De entre la totalidad de posibles escenarios, el escenario RCP8.5 es el que toma en cuenta el índice más alto de incremento en las concentraciones de los gases de efecto invernadero (GEI), mientras que el escenario RCP4.5 se caracteriza por un índice de incremento moderado. El principal objetivo de este análisis es el de inspeccionar los cambios en la temperatura del aire, la precipitación y el nivel medio del mar bajo condiciones de calentamiento global, comparando los cambios calculados de la última parte del siglo XXI (2071-2100) con los últimos 30 años del período de datos históricos (1975-2004). También se presenta, una descripción general de los eventos extremos sobre la región de estudio
INGV-SXG: A Coupled Atmosphere Ocean Sea-Ice General Circulation Climate Model.
No full textINGV CMCCPublished3.7. Dinamica del clima e dell'oceanoope
CMCC-SXF025: A High-Resolution Coupled Atmosphere Ocean General Circulation Climate Model
No full textINGV CMCCPublished3.7. Dinamica del clima e dell'oceanoope
The INGV-CMCC IPCC Scenario Simulations
No full textINGV CMCCPublished3.7. Dinamica del clima e dell'oceanoope
INGV-SXG: A Coupled Atmosphere Ocean Sea-Ice General Circulation Climate Model.
No full textINGV CMCCPublished3.7. Dinamica del clima e dell'oceanoope
Observed shift towards earlier spring discharge in the main Alpine rivers
No full textIn this study, we analyse the observed long-term discharge time-series of the Rhine, the Danube, the Rhone and the Po rivers. These rivers are characterised by different seasonal cycles reflecting the diverse climates and morphologies of the Alpine basins. However, despite the intensive and varied water management adopted in the four basins, we found common features in the trend and low-frequency variability of the spring discharge timings. All the discharge time-series display a tendency towards earlier spring peaks of more than two weeks per century. These results can be explained in terms of snowmelt, total precipitation (i.e. the sum of snowfall and rainfall) and rainfall variability. The relative importance of these factors might be different in each basin. However, we show that the change of seasonality of total precipitation plays a major role in the earlier spring runoff over most of the Alps. (C) 2014 Elsevier B.V. All rights reserved
The INGV-CMCC IPCC Scenario Simulations
No full textINGV CMCCPublished3.7. Dinamica del clima e dell'oceanoope
CMCC-SXF025: A High-Resolution Coupled Atmosphere Ocean General Circulation Climate Model
No full textINGV CMCCPublished3.7. Dinamica del clima e dell'oceanoope
- …
