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We have obtained high-resolution spectroscopy of ten red giants in the Carinadwarf spheroidal (dSph) with UVES at the ESO/VLT. Here we present theabundances of O,Na,Mg,Si,Ca,Ti and Fe. By comparing the iron abundances [Fe/H]with calcium triplet (CaT) metallicities we show that the empirical CaTtechnique yields good agreement with the high-resolution data for [Fe/H]>-2dex, but tends to deviate at lower metallicities. We identify two metal poorstars with iron abundances of -2.72 and -2.50 dex. These stars are found tohave enhanced [alpha/Fe] ratios similar to those of stars in the Milky Wayhalo. However, the bulk of the Carina red giants are depleted in the [alpha/Fe]abundance ratios with respect to the Galactic halo at a given metallicity. Oneof our targets, with a [Fe/H] of -1.5 dex, is considerably depleted in almostall of the alpha-elements by ~0.5 dex compared to the solar values. Such a low[alpha/Fe] can be produced by stochastical fluctuations in terms of anincomplete mixing of single Type Ia and II SNe events into the ISM. Our derivedelement ratios are consistent with the episodic and extended SF in Carina knownfrom its color-magnitude diagram. We find a considerable star-to-star scatterin the abundance ratios. This suggests that Carina's SF history varies withposition within the galaxy, with incomplete mixing. Alternatively, the SF rateis so low that the high-mass stellar IMF is sparsely populated, asstatistically expected in low-mass star clusters, leading to real scatter inthe resultant mass-integrated yields. Both ideas are consistent with slowstochastic SF in dissolving associations, so that one may not speak of a singleSF history at a detailed level (Abridged).

Complexity on Small Scales III: Iron and alpha Element Abundances in the Carina Dwarf Spheroidal Galaxy