diff --git a/source/congrad.f90 b/source/congrad.f90
index ca656a1d31b54dcfb8a6d6fac6d6086ecf0188dd..e88fd53d7181522d1ca2f3c6dcb564f58bf16d13 100644
--- a/source/congrad.f90
+++ b/source/congrad.f90
@@ -403,7 +403,7 @@ subroutine congrad(iter, grad, files, config, fluxes, obs, states, covar)
       end do
     end do
     if ( config%opt_cini ) then
-      tmp(npvar+1:nvar) = tmp(npvar+1:nvar) + config%cinierr * pevecs(jk,npvar+1:nvar)
+      tmp(npvar+1:nvar) = tmp(npvar+1:nvar) + (config%cinierr * pevecs(jk,npvar+1:nvar))**2
     endif
   end do
   ! calculate last part