Cambio Climático y eventos extremos: un enfoque dinámico
Grupo de Física del Clima
E.Sánchez Gómez, A. Ruiz de Elvira, W. Cabos Narváez, F.J. Alvarez García y M.J. Ortiz Beviá
Universidad de Alcalá
Scheme of the talkScheme of the talk
General view:
Current researching activities of the group:
-Climatic Variability
-Empirical Predictability
-Climatic Change
Climate Change and climate extreme events
We focus on:
Colaboration with:
Main topics of GFSC:
Climate variability
- Development of a regional version of a GCM (OPYC) for the Atlantic Ocean.
- Analysis of the interannual variability of the Tropical Atlantic, North Atlantic and Mediterranean Sea.
-Scale interactions and physical mechanisms of the interannual variability: analysis of a coupled ocean-atmosphere GCM simulations with statistical tools
Main topics of GFSC:
Empirical Predictability
- Real retroactive empirical forecasts issued for the Tropical Oceans (Nino3 index, GG index, NTA index).
-Empirical forecast of the North Atlantic air temperature anomalies (also Iberian Peninsula) and of the NAO index.
Empirical predictability in the North Atlantic
Great Anomaly of Salinity (Dickson et al. 1998)
The empirical forecasts are able to detect climatic changes: we observe an evident decrease of predictability in the 80s, caused by significant changes occurred at the end of the 70s: NAO index and the GSA (SanchezGomez et al. 2001).
First EOF of sea ice field in the North Atlantic (66%)
Changes in the NAO phase
Main Topics of GFSC:
Climatic Change
- Colaboration with the Departamento de Puertos del Estado (WASA group). Detection the swell changes in the north coast of Spain, with he help of the swell simulations from the WAM model.
- Characterization of climatic changes in the Spain (Meseta Sur).
Climate extreme events! (indices proposed by WMO-CCI/CLIVAR)
Climate change and extreme climate events
Weather regimes approach
- Four classical weather regimes in the North Atlantic basin in winter and in summer (Vautard 1990).
- They have been identified by a cluster technique (k-means, Michelangeli et al. 1991) from 500 mb field (ERA40).
We can find the links between the weather regimes and some extreme climate events over a region (Spain).
1.
2.
The simulations from ARPEGE-Climat model (control and scenario) allow us for determining the possible changes in the percentage of occurrence of a weather regime. Then we can somehow ‘predict’ the changes in frequency of an extreme climate event.
3.
Climate change and extreme climate eventsWeather regimes in ERA40 (winter)
Greenland Anticyclone(GA) 7j 16%
Atlantic Ridge (AR) 6j 16%
Blocking (BL) 6j 17%
Zonal (ZO) 8j 22%
Climate change and extreme climate eventsWeather regimes in ERA40
(summer)Greenland Anticyclone(GA) 7j 11%
Atlantic Ridge(AR) 6j 15%
Blocking (BL) 6j 14%
Zonal (ZO) 7j 12%
Climate change and extreme climate events
- Extreme events are identified by a threshold value (5%, 95% quantiles).
- Variables: Tmax, Tmin, Precipitation, Storm Tracks
Extreme climate events
Threshold value
5%
PX
%
Change of probability:
C = (Px/5)-1) *100
Px=10; C=100%
Px=15; C=200%
Px=0; C=-100% !!
Climate change and extreme climate eventsExtreme climate
eventsSome applications already carried out in France (SQR data)
Zonal
Blocking
Blocking
Winter precipitationWinter Tmin Summer Tmax
Next: 53 meteorological stations Tmin, Tmax and precipitation in Spain (Meseta Sur) provided by the INM.
SánchezGómez E., Gosetlogon G de, L. Terray and A. Joly (2005) ‘Weather regimes links with Temperature and precipitation extremes’, Climate Dynamics, (submitted).
Climate change and extreme climate eventsExtreme climate events : Storms
(With the help of storm tracking carried out by A. Joly and F. Ayrault)
Atlantic Ridge
Greenland Anticyclone
Blocking Zonal
Climate change and extreme climate eventsWeather regimes in ARPEGE-Climat
Stretched grid, Variable Resolution
~ 60 Km over France and Spain
~ 600 Km over the Southern Pacific
(Déqué et al. 1998)
Data:
-3 simulations of control (1960-1999)
-3 simulations of scenario A2 from IPCC (2070-2099)
Climate change and extreme climate eventsWeather regimes in ARPEGE-Climat
(winter)
Climat Présent
Climat Futur
ERA40
GA
AR
BL
ZO
22%
24%
24%
30%
28%
24%
21%
27%
8%
18%
35%
39%
± 6%
± 2%
± 3%
± 3%
Climate change and extreme climate eventsWeather regimes in ARPEGE-Climat
(winter)
Climat Présent
ERA40
GA
AR
BL
ZO
22%
24%
24%
30%
28%
24%
21%
27%
8%
18%
35%
39%
Climate change and extreme climate eventsWeather regimes in ARPEGE-Climat
(summer)
Climat Présent
ERA40
GA
AR
BL
ZO
29%
22%
24%
25%
27%
26%
21%
26%
5%
2%
70%
23%
± 1%
± 4%
± 4%
± 2%
Climate change and extreme climate eventsWeather regimes in ARPEGE-Climat
(summer)
Climat Présent
Climat Futur
ERA40
GA
AR
BL
ZO
29%
22%
24%
25%
27%
26%
21%
26%
5%
2%
70%
23%
!
Conclusions:
Main topics of GFSC
Climatic Variability (Atlantic Ocean, ENSO)
Empirical Predictability
Climatic Change
Impact of climatic change in the frequency and intensity of the climate extreme events (Meseta Sur)
