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26<br />

There is nevertheless a large agreement between<br />

experiments. For a given month, the spatial pattern is very<br />

similar, and in fact the spatial correlation is around 90%.<br />

This means than the spatial warming patterns found are an<br />

inherent characteristic of the domain and the month, not a<br />

feature of the GCM neither the SRES scenario used to<br />

perform the simulation.<br />

In the temporal evolution, the importance of different<br />

scenarios and GCM is found. In the A2 scenario the<br />

warming signal is stronger, and it is reflected in a larger<br />

trend in the Principal Component associated to the first<br />

EOF.<br />

climático sobre la Península Ibérica. Asamblea<br />

Hispano Portuguesa de geodesia y geofísica, 2006.<br />

von Storch, H. and F.W. Zwiers. Statistical Analysis in<br />

Climate Research. Cambridge University Press, 2007.<br />

Zorita, E., J.F. Gonzalez-Rouco, H. von Storch, J.P.<br />

Montavez, and F. Valero. Natural and anthropogenic<br />

modes of surface temperature variations in the last<br />

thousand years. Geophys. Res. Lett., 32(8):755 – 762,<br />

2005.<br />

There is also an important difference in the evolution of<br />

maximum and minimum 2-m temperatures along the XXI<br />

century. The maximum temperatures suffer a higher<br />

warming. This could yield in a an increase of the daily<br />

temperature range.<br />

Finally, the amount of warming has also an annual cycle.<br />

Both the maximum and minimum temperatures have a more<br />

marked trend in summer months. This means than the<br />

climate could become more continental in the future.<br />

5. Conclusions<br />

A study of the warming patterns over the IP under several<br />

scenarios and with different GCM has been performed using<br />

a climate version of MM5 mesoescalar model. An EOF<br />

analysis has been employed in order to reduce the noise in<br />

the warming of 2-m maximum and minimum temperature<br />

and reduce the dimensionality of the problem.<br />

It has been found that the first EOF accounts for the main<br />

warming pattern, and this depends on the month and on the<br />

variable. There is an important annual cycle and an<br />

asymmetry in the behavior of maximum and minimum<br />

temperatures.<br />

The most important result is that these projections are<br />

consistent under different scenarios and using different<br />

GCM coupled to the regional climate model. The only<br />

difference between scenarios is the intensity of these<br />

changes in the IP climate, not the qualitative features.<br />

Finally, the spatial structure of the warming patterns seems<br />

to be related to several physical parameters like<br />

continentality or height over the sea. Further research should<br />

be devoted to fully understand these changes, which could<br />

be related to changes in the global circulation.<br />

As future work, others simulations should be performed<br />

driven by other GCM. Also, other task involve checking<br />

whether these patterns are also present for pre-industrial<br />

climate, as obtained by others authors<br />

6. References<br />

Diffenbaugh, N.S., J.S. Pal, F. Giorgi, X.J. Gao. Heat stress<br />

intensification in the Mediterranean climate change<br />

hotspot. Geophys.Res. Lett., 34(11):53 – 70, 2007.<br />

Giorgi, F. Climate change hot-spots. Geophys. Res. Lett.,<br />

33(8):11217 – 11222, 2006.<br />

IPCC. Climate Change 2007 – The Physical Science Basis.<br />

WMO, 2007.<br />

Montávez, J.P., J. Fernández, J.F. González-Rouco, J. Saenz,<br />

E. Zorita, and F. Valero. Proyecciones de cambio

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