<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"><base href="x-msg://110/"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><br></div><div>Hi Marc</div><div><br></div><div>You are experiencing the famous chaotic nature of the atmosphere caused by the software system dependency </div><div>, which was noted earlier by Prof. Lorenz. Bit-wise exact output for different number of CPUs on a MPI platform would </div><div>be a necessary condition for bug-free. Object measure of the tolerance in differences due to dissimilar software </div><div>could be rather difficult in regional models due to another factor in lateral boundary forcing.</div><div>The attached is a paper dealing with this issue in a global model.</div><div><br></div><div>Cheers,</div><div><br></div><div>songyou</div><div><br></div><div><br></div></body></html>