Fortran has certainly been very important but now people are building climate models faster in Julia and with better performance. Fortran used to be the only option for high performance numerical computing but that is no longer the case. For instance preliminary performance tests of BLAS rebuilt for Julia shows higher performance than the Fortran variants which have been tuned for decades.

Part of the reason Julia can do this is due to support for parametrized types and JIT compilation which I can make it possible to in-line a lot of code which you cannot inline with AOT compilation.