| 1. |
- Döscher, Ralf, et al.
(författare)
-
The EC-Earth3 Earth system model for the Coupled Model Intercomparison Project 6
- 2022
-
Ingår i: Geoscientific Model Development. - : Copernicus GmbH. - 1991-959X .- 1991-9603. ; 15:7, s. 2973-3020
-
Tidskriftsartikel (refereegranskat)abstract
- The Earth system model EC-Earth3 for contributions to CMIP6 is documented here, with its flexible coupling framework, major model configurations, a methodology for ensuring the simulations are comparable across different high-performance computing (HPC) systems, and with the physical performance of base configurations over the historical period. The variety of possible configurations and sub-models reflects the broad interests in the EC-Earth community. EC-Earth3 key performance metrics demonstrate physical behavior and biases well within the frame known from recent CMIP models. With improved physical and dynamic features, new Earth system model (ESM) components, community tools, and largely improved physical performance compared to the CMIP5 version, EC-Earth3 represents a clear step forward for the only European community ESM. We demonstrate here that EC-Earth3 is suited for a range of tasks in CMIP6 and beyond.
|
|
| 2. |
- Meccia, Virna L., et al.
(författare)
-
Internal multi-centennial variability of the Atlantic Meridional Overturning Circulation simulated by EC-Earth3
- 2023
-
Ingår i: Climate Dynamics. - : Springer Science and Business Media LLC. - 0930-7575 .- 1432-0894. ; 60:11-12, s. 3695-3712
-
Tidskriftsartikel (refereegranskat)abstract
- We report a multi-centennial oscillation of the Atlantic Meridional Overturning Circulation (AMOC) simulated by the EC-Earth3 climate model under the pre-industrial climate. This oscillation has an amplitude of ~ 6 Sv and a period of ~ 150 years and significantly impacts the atmosphere. We find that it is a self-sustained low-frequency internal variability, driven by the accumulation of salinity anomalies in the Arctic and their release into the North Atlantic, affecting the water column stability and the deep convection. Sea ice plays a major role in creating the salinity anomaly in the Arctic, while the anomalous Arctic oceanic circulation, which drives the exchange of liquid freshwater between the Arctic and the open ocean, is the main responsible for its southward propagation. Interestingly, EC-Earth3 simulations with increased greenhouse concentrations, and therefore under a warmer climate, do not exhibit these strong AMOC fluctuations. We hypothesize that in a quasi-equilibrium climate with a global air surface temperature 4.5° higher than the pre-industrial period, the low amount of sea ice in the high latitudes of the North Atlantic is no longer able to trigger the mechanism.
|
|
| 3. |
- Messori, Gabriele, et al.
(författare)
-
On the low-frequency variability of wintertime Euro-Atlantic planetary wave-breaking
- 2019
-
Ingår i: Climate Dynamics. - : Springer Science and Business Media LLC. - 0930-7575 .- 1432-0894. ; 52:3-4, s. 2431-2450
-
Tidskriftsartikel (refereegranskat)abstract
- Planetary wave-breaking can lead to large-scale atmospheric circulation anomalies and favour high-impact weather occurrences. For example, the simultaneous occurrence of anti-cyclonic wave-breaking to the south of the North Atlantic jet and cyclonic wave-breaking to the north, here termed double wave-breaking, has been linked to heightened frequencies of explosive cyclones in the Atlantic basin and destructive windstorms over Western and Continental Europe. The present study analyses the long-term temporal variability of wintertime cyclonic and anti-cyclonic wave-breaking, and the resulting double wave-breaking, in the North Atlantic. We use reanalysis data, proxy reconstructions of the North Atlantic Oscillation (NAO) and a 1000-year coupled global climate model equilibrium simulation under constant pre-industrial forcing. The wave-breaking wavelet spectra highlight a significant ultra-centennial variability in double wave-breaking frequency, which is largely mirrored in the variability of the NAO. However, we note that the NAO wavelet spectra in the different datasets display significant discrepancies. The low-frequency wave-breaking variability is reflected in long-term anomalies of the large-scale atmospheric circulation in the Euro-Atlantic sector. The 100-year periods with the most and least double wave-breaking occurrences display significant and opposite anomalies in both upper and lower-level wind, as well as in the frequency of extreme temperature events and in the magnitude of wind destructiveness over Europe. The latter broadly resembles the wind destructiveness anomalies associated with individual double wave-breaking instances in reanalysis data. The existence of low-frequency variability in an atmospheric pattern related to high-impact weather events has important implications for the study and interpretation of climate change projections and of possible future NAO changes.
|
|
| 4. |
|
|
| 5. |
- S. Valvo, Paolo, et al.
(författare)
-
The European project SUREBridge - A case study in Tuscany
- 2017
-
Ingår i: AIMETA 2017 - Proceedings of the 23rd Conference of the Italian Association of Theoretical and Applied Mechanics. - 9788894248470 ; 2
-
Konferensbidrag (refereegranskat)abstract
- The European project SUREBridge (Sustainable Refurbishment of Existing Bridges) is developing a new concept for the refurbishment of road bridges. The proposed technique takes advantage of the peculiarities of fibre-reinforced materials to perform upgrading, repair, and strengthening in an effective and efficient way in terms of resource consumption, waste production, construction time, and traffic disruption. The technique applies to bridges with reinforced concrete slab and longitudinal girders made of either reinforced concrete or steel. Longitudinal girders are strengthened by bonding carbon fibre-reinforced polymer (CFRP) laminates to their bottom surfaces. Higher structural performances are achieved by pre-stressing the CFRP laminates. The existing concrete slab is not demolished, with savings in both construction time and waste production. Instead, tailor-made glass fibre-reinforced polymer (GFRP) panels are connected to the deck to increase its overall bending strength. Furthermore, GFRP panels enable the widening of the road section, if necessary to upgrade the bridge to increased traffic demand. This paper presents the application of the SUREBridge technique to a real bridge located in San Miniato, Tuscany, Italy. The designed intervention includes both the widening of the road section and the structural strengthening of the deck to comply with current traffic load.
|
|
