  We construct net baryon number and strangeness susceptibilities as well as
correlations between electric charge and strangeness from experimental data of
the ALICE Collaboration at the CERN LHC. The data were taken in Pb-Pb
collisions at $\sqrt{s_{NN}}$=2.76 TeV. The resulting fluctuations and
correlations are consistent with Lattice QCD results at the chiral crossover
pseudocritical temperature $T_c\simeq 155$ MeV. This agreement lends strong
support to the assumption that the fireball created in these collisions is of
thermal origin and exhibits characteristic properties expected in QCD at the
transition from the quark gluon plasma to the hadronic phase. The volume of the
fireball for one unit of rapidity at $T_c$ is found to exceed 4000 fm$^3$. A
detailed discussion on uncertainties in the temperature and volume of the
fireball is presented. The results are linked to pion interferometry
measurements and predictions from percolation theory.
