136 PALAEOCLIMATES Figure Model simulated mean seasonal temperatures for the Norian for (A) December February and (B) June August Units are C and the contour interval is every C The ocean sea surface temperatures were prescribed JJA, June, July, August; DJF, December, January, February Temperature-limited facies According to the model, low temperatures would not have been a significant barrier to coral reef development around the Tethys Reef systems developed and diversified through the Triassic, extending their range from between 2 S and 25 N in the mid-Triassic to a maximum range of 35 S to 33 N in the Late Triassic Range limits are very close to the 20 C isotherm in the model Precipitation (Figure 3) Large tracts of Pangaea between about 40 N and 40 S are modelled to receive very little rainfall Much of the rainfall is over the oceans, being convective in character, with the main zone of rainfall migrating north and south through the year with the movement of Intertropical convergence zone (ITCZ) The equatorial lands surrounding eastern and southern Tethys are modelled to receive relatively little rainfall during December–April North-eastern Gondwana is modelled to have a monsoonal climate (winter wet) Northern and eastern Siberia have some rainfall throughout the year, the wettest period generally being through June and the