A crash course in changing the world.
As I am living in Lower Saxony I don´t think that there will be any crises we have to face in the feoreseeable future, but of course there are some in Germany that already happenede and might happen again some day.
The one thing I could remember is the flood in Dresden in 2002, here is a video showing some pictures and information about it:
In a situation like this I think it´s most important to track data about the height of the water in every village or city which already is or might be affected by the flood, so that people can prepare and pack their stuff together to leave their home as fast as possible.
It´s also important to tell the people where they could go to and be safe if they really have to leave, so that there would be no confusion where to go to or panic situations.
The villages/cities should have people with a checklist or something like this to check if everybody is safe and nobody was left behind (I know in big cities this would be quite hard to manage, but I think it´s possible anyhow).
Of course this data should be updated quite often and people in the "safety-camps" should be able to check the status of their family members, friends etc. any time and share the infomation on other social networks etc. to help gaining attention and informing a lot more people.