msci Code

function calc_theta, temp, plevs, p0, kappa=kappa
  if n_elements(p0) eq 0 then p0=1000
  if n_elements(kappa) eq 0 then kappa=0.2857

  theta=temp
  for p=0, n_elements(plevs)-1 do begin
    theta[*,*,p]=temp[*,*,p]*(p0/plevs[p])^kappa
  endfor
  return, theta
end