If a risk has appeared it doesn't necessarily mean the event has occurred. The first thing the PM should do is add the risk to the Risk Register and review with the team to develop a response. If the response would trigger a change to the baseline, then appropriate change management should be followed. But only if the response would impact your baseline.

if risks have appeared during project execution and project manager did not foresee these risks during planning what should the project manager calculate to address this critical budgetary situation
on the other hand if the contingency reserve shall to be used that mean cost base line has to be modified to add the cost of these new risks so integrated change control process shall be occurred
my question is change request shall be prepared and forward to CCB if any new risks appeared or during implementation of response after trigger condition has occurred.